TIGHAR
Amelia Earhart Search Forum => Aircraft & Powerplant, Performance and Operations => Topic started by: Gary LaPook on November 24, 2011, 12:52:05 PM
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There is now incontrovertible proof that the plane did NOT land on Nikumororo. NBC news reported that the Airworthiness Certificate for the airplane was just discovered in California and that this Airworthiness Certificate must be carried in the plane at all times, so this means that the plane was secretly brought back to the U.S. and then disposed of. Since the plane made it back to the U.S. it could not possibly be found on Niku.
See the NBC stories available here:
http://video.msnbc.msn.com/nightly-news/45417206/#45417206
gl
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Obviously the plane never left California by air. I well remember my ground school instructor explaining that it wasn't horsepower, nor aerodynamics, nor even Bournoulli's principal that enabled an airplane to fly, it was the airworthiness certificate. Without it, an airplane could not fly, and that was that!
I now believe that those odd little aluminum clips found on Niku were supposed to hold the certificate. They were on Niku, not attached to anything at all, simply because there was no certificate to hold, and no aircraft to hold it to. Therefore they were not aircraft parts, which also explains the difficulty explaining what they are. If they were aircraft parts, they would be in California, with the rest of the missing aircraft.
The two people who flew away from Lae in 1937 must have been Japanese tourists. If they were on a secret spying mission, that would explain everything.
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thats probably from the first attempted flight that failed, as she would have needed a second 1 to confirm plane was airworthy after crashing
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also that cetificate is dated 15 august 1937
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thats probably from the first attempted flight that failed, as she would have needed a second 1 to confirm plane was airworthy after crashing
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Except that new airworthiness certificates are not issued after a crash and repair, planes continue with the original airworthiness certificate which is issued when the airplane is first manufactured, it only certifies that the plane is airworthy when manufactured. Repairs and inspections needed to confirm continuing airworthiness are contained the in maintenance log books.
gl
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also that cetificate is dated 15 august 1937
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No, it's dated 7-36.
gl
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sorry that expiry date ov certificate ::) but makes u wonder why it was for so long
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A mechanic that worked for Paul Mantz... with all kinds of memorabilia.... I wonder if there might be photographs of the repairs made to the Electra after the first world attempt? How about more detailed photos of the rear cabin that might show "dado's" or any manner of useful tidbits....
Brad
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"incontrovertible proof"?? Sorry, Gary. Finding the airworthiness certificate in a box of memorabilia owned by an aircraft mechanic who worked for Paul Mantz is certainly not " incontrovertible proof ". An interesting keepsake for sure, but no proof of anything, other than maybe that the plane didn't crash and sink, at least not with that certificate aboard as it doesn't appear to be water damaged. I guess one could say that the plane could have water landed and been recovered floating and that would explain the certificate not getting wet. Problem is, according to the radio experts and the post-loss radio transmissions that are credible, the plane couldn't transmit while floating. That doesn't preclude the possibility that the plane landed on a beach or reef, trnsmitted, and then washed away to be recovered while floating around. That leads to another issue, for the plane to have been recovered, either from a beach/reef or afloat, a salvage ship would have been required. Remember, there were no heavy-lift helicopters in 1937. A ship large enough to hoist the plane aboard would have to have a reasonable large crew. I find it hard to believe, though not impossible, that not one crewmember ever mentioned to anyone having salvaged the plane or crew. I giess that the plane could have been disassembled if on shore and then packed and shipped back to California and that is how the certificate made its way into the mechanics box. I think it much more likely that the mechanic obtained the certificate while repairing the plane after the failed first attempt. I understand that planes can't legally fly without the certificate aboard. In my limited flight experience I have never once seen a pilot waving the certificate out the window so the tower can see it before receiving permission to take off. I think a plane can fly just fine without that peice of paper aboard, just as unregistered cars can drive just fine or unlicensed drivers as well. For the record, I've written lots of tickets to unlicensed drivers and drivers of unreistered/uninsured cars so I can tell you from first hand experience that not having a piece of paper does not prevent the car, or plane for that matter, from functioning just fine. As far as proof goes, if that certificate had been found nailed to a wall (or maybe held iin place by the mystery clips) in a shack on Nikumararu it would carry more weight as to the plane having been there than it does having been found in a box owned by an aircraft mechanic in California with a connection to the plane through Paul Mantz. Same goes for any serialized parts. Find me a part from the plane in California that you can prove came from the plane after it left Lae and I'll believe the plane was recovered. Find me a part on Nikumararu and I'm more inclined to believe the flight ended there. Find me a substantial part of the airframe itself and not a replacable part and I'll believe you've found the plane. I think the mechanic obtained the certificate while the plane was being repaired and kept it as a momento. Would anyone have noticed that it wasn't there before or at any point during the flight(s)? If it had been noticed, would anyone have really considered it a big enough deal to delay the flight(s) or announce that it was missing? I still believe that the plane landed on Nikumararu and that parts of it are still there today. There is simply too much evidence to support that. The airworthines certificate does nothing to refute that, at least not to me. LTM, -John
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Ric's Research Bulletin (http://tighar.org/Projects/Earhart/Archives/Research/Bulletins/61_FuelSystem/61_FuelSystem.htm)on the fuel system gives some of the licensing chronology.
"On October 29, 1936 George Putnam wrote to the Bureau of Air Commerce to straighten out some confusion about the airplane’s license which described it as having a fuel capacity of only 394 gallons. The airplane had originally been licensed by Lockheed in the Experimental category with the 1,198 gallon system. After it was sold to Earhart, she licensed the Electra in the Restricted category in August during a brief period when the fuselage tanks had been removed to install a “false floor” (no explanation). The airplane had never, therefore, been licensed in the Restricted category with the long-range fuel system installed. In the October 29 letter Putnam stated that “the existing tankage ... is identical with that in the ship at the time of the first license.” In other words, 13 tanks totaling 1,198 gallons.
The Bureau, of course, required an inspection before issuing a new license. When the airplane was inspected and licensed on November 27, 1936 the 51 gallon fuselage tank was gone, and the 100 gallon wing tanks (in the baggage lockers behind the engines) were now 102 gallons. Total fuel capacity was now 1,151 gallons."
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Everybody,
I'm sure Gary was joking about the 'incontrovertible proof.'
There is no mystery about the documents. We have copies of the same paperwork. We're still working along on getting the full file of BAC documents and correspondence relating to c/n 1055 rendered legible so that we can put it up on the TIGHAR website.
Briefly:
On July 19, 1936 Lockheed registered c/n 1055 in the Experimental category as X16020. At that time the plane had a total of 13 fuel tanks with a total capacity of 1,198 gallons.
On July 24, 1936 the airplane was sold to Amelia Earhart. At that time the registration painted on the airplane was X16020.
Some time after July 24 but before August 6, Earhart had the number repainted to NR16020 and filled out the application form that is shown in the on-line slideshow. That application was rejected (note that it has no date or inspector name).
On August 6 she submitted a new application. At that time the fuselage tanks had been temporarily removed and the airplane's total fuel capacity was only 394 gallons. The application was accepted on August 7 and the airplane was registered in the Restricted category - but not approved for international flight. The number was changed to R16020 and on August 18 1936 the certificate shown in the on-line slideshow was issued. (Our copy of that same certificate has the stamped date "August 18 1936" at the top.)
The airplane was approved for international flight on September 21, 1936 and the BAC authorized the number to be changed to NR16020.
In late October, the BAC noticed the discrepancy between the airplane's actual fuel capacity (the fuselage tanks had been reinstalled) and the current license. Putnam replied, saying that the tanks had been out for only a short time and the total capacity should be 1,148 gallons - which was a typographical error - the correct number at that time was 1,198 gallons.
The BAC issued an amended certificate showing the total capacity as 1,148 gallons.
In November the fuel system was modified and on November 27, 1936 a new application was accepted showing 12 tanks and a total capacity of 1,151 gallons. Another amended certificate was issued, this time not showing any fuel capacity.
Following the rebuild in April/May yet another application was made and yet another amended amended certificate was issued. This one showed the correct fuel capacity of 1,151 gallons. The original of that certificate is the one that should have been aboard the airplane on July 2, 1937.
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why does the certificate say the plane is for research aswell, or would an around the world attempt be classed as research ?
as to see if it was possible
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why does the certificate say the plane is for research aswell, or would an around the world attempt be classed as research ?
as to see if it was possible
Earhart and Putnam called the plane a "flying laboratory." It's alleged purpose was research. The world flight was supposedly a research flight.
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thats probably from the first attempted flight that failed, as she would have needed a second 1 to confirm plane was airworthy after crashing
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Except that new airworthiness certificates are not issued after a crash and repair, planes continue with the original airworthiness certificate which is issued when the airplane is first manufactured, it only certifies that the plane is airworthy when manufactured. Repairs and inspections needed to confirm continuing airworthiness are contained the in maintenance log books.
gl
Agree that what you say is the norm today, Gary. But, things were a bit different under the Bureau of Air Commerce in the '30's - tickets expired after a year and a new C of A would be issued upon a new finding of airworthiness.
Another reason this may have happened is one of the causes given for revocation of a C of A in CAR 0 policy of the day: 'failure to maintain the aircraft in an airworthy condition'. Although it can be argued that a restoration to airworthy condition was planned, NR16020 definitely was not in an airworthy state after the Luke Field crash - and a new finding would have to have been made before she could be returned to service.
Today that simply means the 'permanent' certificate is not valid until airworthiness is found and appropriately documented by someone enabled to do so under FAR 43, including for the purposes of major repairs, etc. But in NR16020's day a new certificate was required upon that finding - hence the old term 'relicensing' with annual every year. The same would logically apply to a wrecked airplane.
It is not a stretch then to see an inspector voiding the existing certificate when NR16020 showed up with major damage. The 'punch holes' further suggest this course - that is still a means used to this day when a certificate is voided or revoked, but returned to the owner for the file. Additional pressure to do this could also have come from the nature of the bird (highly modified) and the nature of its intended operations - these would be seen, then and now, as 'high-risk / high-visibility' issues, which tend to make authorities extra-cautious in dealing with such things.
I suspect some of this was the case for NR16020. There could have been other reasons - including something as simple as needing to replace a 'lost' certificate, misplaced while work was going on at the Mantz facility. Had that been the case, and the original turned up later, the late-found certificate could easily have been 'punched' (as this one was) to render it invalid - and given over for the file, later turning-up as a keep-sake.
There's also the possibility that somehow, in the middle of all AE's sterling planning, and, despite much excellent execution of details, like radio-handling arrangements and the like, that the certificate was simply overlooked... ; ) That has happened more than once in this world. I can hear it now, as Fred Noonan was ripping the certificate frame off a bulkhead (by tearing out the little hand-made gidgies that held it there...) - "AE - looks like we got away without the CERTIFICATE! You're going to be in hot water when we get back to Oakland...".
Later, some lucky chap finding himself in possession of an artifact that had been among his bosses possessions may have 'done the right thing' and had BAC (or if a bit later, CAA) punch the ticket. That just seems odd though - it really seems more likely the authorities had this in their possession when NR16020 showed up for major repairs, punched it and returned it for NR16020's own records, only to have it turn up as a keep sake later.
This chap's stuff would be lovely to comb through. Maybe there are others, too. Mantz was colorful - and most may recall that he died filming 'Flight of the Phoenix' (the original - with REAL aviation stunt work). Perhaps he left behind a hangar full of goodies that got sifted out here and there - maybe more records from the day, including photos, will yet turn-up. That could really be helpful.
In any case, good find, Gary, and it is very interesting to see this artifact - however it came to be where it was found!
And, surely you had tongue-in-cheek as you mentioned 'incontrovertible proof' that NR16020 could not have wound up anywhere other than where this certificate found itself? One hopes... ; )
LTM -
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I noticed all the points you bring up, so we agree on this.
Here is the link to the reently found documents.
http://www.nbclosangeles.com/news/local/New-Amelia-Earhart-Photos-134331928.html
The "Restricted Aircraft License", is image 20 in the collection, and the story says that it must be in the plane at all times so how did it show up in California when the plane was supposed to have disappeared?
Before anybody goes off on some conspiracy theory based on this, this document is not a "Standard Airworthiness Certificate" (even though the story identifies it as such.) I am attaching an example of one. A Standard Airworthiness Certificate is a permanent document, it never expires, and it stays in the plane forever. This document is limited in its duration since it expires by its own terms in August 1937. It is very similar to the current "Special Airworthiness Certificate" which is issued for non-standard aircraft and operations and so has restrictions on the operation of the plane and it's duration. See attached examples. Image 20 is the superseded license and a new, and current one, would have been issued and carried in the plane on the last flight. August 1937 would have been cutting it pretty close on the world flight so Earhart applied for a new one after the plane was repaired. Note the two holes punched in the document which shows that this document was canceled and was no longer valid.
Further, images 18 and 19 is the application for the aircraft license, image 20. The application is dated July 1936 and lists the fuel tanks, 2 @16gal; 2 @ 81; 2 @118; 2 @ 100; 3 @ 149; 1 @ 70 and 1 @ 51 gal, a total of 1198 gallons. We know that the 51 gallon tank was removed. Removal of the 51 gallon tank and changing the capacity of the 100 gallon tanks to 102 brings the total to the 1151 we are familiar with. Since image 20 was issued based on these numbers it was also necessary for a new license to be obtained after the one tank was remove which, again, explains why image 20 did not disappear with Earhart.
I think the discrepancy between the 100 gallons listed on the original July 1936 application for a license and the 102 gallons listed for the wing tanks is most likely a simple error. The blueprints for the fuel system lists the tanks as 102 gallons but the blueprints are dated later so that doesn't clear up the mystery. Anyway, we can be sure that they didn't rip out the 100 gallons tanks to be replaced by 102 gallon tanks after the Luke field crash, the wings didn't sustain a lot of damage and the blueprints are dated prior to the crash. And it would be hard to justify the expense of taking the wings apart to install tanks that held only two gallons more. If they needed an extra four gallons it would have been a lot easier and cheaper to modify one of the fuselage tanks.
gl
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ok thx Ric was just querying :)
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Everybody,
I'm sure Gary was joking about the 'incontrovertible proof.'
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You know I just like to stimulate discussion.
gl
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It is all Quantum Mechanics (or String Theory). There is a wave function connecting the wings and the CA that has a "1" (plane can fly) if and only if the wings and the CA are present on/in the plane.
Since the CA was in California ( in the suitcase in thhe closet) and the plane was in New Guinea, it couldn't takeoff in our dimensions so it went into that alternate universe paralelling ours where it found an alternate CA and was thus able to fly and reach its destination.
Now if we can just find that alternate Howland Island we will find the plane and AE/FN
LOL
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I noticed all the points you bring up, so we agree on this.
See my explanation above. We don't have to speculate about this. We have the documents.
I think the discrepancy between the 100 gallons listed on the original July 1936 application for a license and the 102 gallons listed for the wing tanks is most likely a simple error since the blueprints for the fuel system lists the tanks as 102 gallons and the blueprints are dated prior to the first flight. Anyway, we can be sure that they didn't rip out the 100 gallons tanks to be replaced by 102 gallon tanks after the Luke field crash, the wings didn't sustain a lot of damage.
Strange as it seems, I think the facts argue for the actual replacement of the 100 gallon tanks with 102 gallon tanks. The tanks were consistently listed as being 100 gallons until November 1936 and consistently listed as 102 gallons thereafter. There is even a photo of them apparently being worked on.
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I noticed all the points you bring up, so we agree on this.
See my explanation above. We don't have to speculate about this. We have the documents.
I think the discrepancy between the 100 gallons listed on the original July 1936 application for a license and the 102 gallons listed for the wing tanks is most likely a simple error since the blueprints for the fuel system lists the tanks as 102 gallons and the blueprints are dated prior to the first flight. Anyway, we can be sure that they didn't rip out the 100 gallons tanks to be replaced by 102 gallon tanks after the Luke field crash, the wings didn't sustain a lot of damage.
Strange as it seems, I think the facts argue for the actual replacement of the 100 gallon tanks with 102 gallon tanks. The tanks were consistently listed as being 100 gallons until November 1936 and consistently listed as 102 gallons thereafter. There is even a photo of them apparently being worked on.
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The blueprints are dated March 12, 1937 showing the 102 gallon tanks. Since they changed the capacity prior to the crash in Hawaii we know that it wasn't a change done while the plane was being repaired. Just a guess but maybe they figured that the tanks held 100 gallons and then by actual measurement they found that they actually held 102, maybe taking the filler necks into account, its a long way from the fuel caps in the nacelles to the 102 gallon tanks behind the spars.
gl
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I found the story about finding the C of A interesting. I wonder if anyone knows if this mechanic was one of those who worked on NR16020 after the accident at Luke Field. Too late for an interview of course, but maybe the cache of memorabilia contains details of the repairs made that might match up with the material found on Niku.
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It would be cool to find a stash of records on the repairs - SOMETHING must be out there somewhere... wonder who else worked for Mantz who might still have a dusty box in the attic?
We have the detailed repair orders and will put them on the TIGHAR website. What we don't have - and probably never existed - is a record of exactly how the repairs orders were carried out.
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Let's see, 2 tanks with 2 gallons more equals 4 gallons. Assuming 40 gallons per hour fuel management, that represents 1/10th hour or 6 minutes which, at 133 mph represents about 13 miles. Could be the difference between getting wet and landing on a reef.
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I noticed all the points you bring up, so we agree on this.
See my explanation above. We don't have to speculate about this. We have the documents.
I think the discrepancy between the 100 gallons listed on the original July 1936 application for a license and the 102 gallons listed for the wing tanks is most likely a simple error since the blueprints for the fuel system lists the tanks as 102 gallons and the blueprints are dated prior to the first flight. Anyway, we can be sure that they didn't rip out the 100 gallons tanks to be replaced by 102 gallon tanks after the Luke field crash, the wings didn't sustain a lot of damage.
Strange as it seems, I think the facts argue for the actual replacement of the 100 gallon tanks with 102 gallon tanks. The tanks were consistently listed as being 100 gallons until November 1936 and consistently listed as 102 gallons thereafter. There is even a photo of them apparently being worked on.
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The blueprints are dated March 12, 1937 showing the 102 gallon tanks. Since they changed the capacity prior to the crash in Hawaii we know that it wasn't a change done while the plane was being repaired. Just a guess but maybe they figured that the tanks held 100 gallons and then by actual measurement they found that they actually held 102, maybe taking the filler necks into account, its a long way from the fuel caps in the nacelles to the 102 gallon tanks behind the spars.
gl
I have a hunch you are right, Gary.
I agree.
From the point of view of going anal to add that little tad of fuel, it would have been far more productive to lash a 5 gallon jerry can down in the cabin.
LTM -
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I was going to say that, too.
gl
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It is all Quantum Mechanics (or String Theory). There is a wave function connecting the wings and the CA that has a "1" (plane can fly) if and only if the wings and the CA are present on/in the plane.
Since the CA was in California ( in the suitcase in thhe closet) and the plane was in New Guinea, it couldn't takeoff in our dimensions so it went into that alternate universe paralelling ours where it found an alternate CA and was thus able to fly and reach its destination.
Now if we can just find that alternate Howland Island we will find the plane and AE/FN
So, are you saying that the Star Trek AE episode was actually a Documentary?
LTM,
Don
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The additional 243 lbs could possibly have affected the takeoff roll and since she had 1110.5 gallons and plenty of range (endurance) for the proposed leg it was probably prudent to go without the 40.5 gallons. I might have considered gassing up and leaving Fred behind. MHO
Lockheed report 487, page 2, shows the takeoff distance for a fully loaded L-10E at 16,500 pounds to be 2100 feet at sea level. Takeoff distance varies with gross weight squared. For the takeoff at Lae the plane weighted about 14,000 pounds. 14,000/16,500 = 0.848 which squared equals 0.719 times 2100 feet means the takeoff at Lae should have taken 1,512 feet. Adding 243 pounds of fuel, and doing the same calculation results in a takeoff distance of 1,565 feet, only 53 feet longer, not much to worry about.
gl
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I might have considered gassing up and leaving Fred behind. MHO
Or maybe she should have left behind all that heavy gold bullion. ;)
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For the takeoff at Lae the plane weighted about 14,000 pounds. 14,000/16,500 = 0.848 which squared equals 0.719 times 2100 feet means the takeoff at Lae should have taken 1,512 feet. Adding 243 pounds of fuel, and doing the same calculation results in a takeoff distance of 1,565 feet, only 53 feet longer, not much to worry about.
gl
Is your point that she should have considered 3000 feet plenty enough runway since the plane theoretically should have been able to get wheels off the ground in 1565 feet? And does that figure take into account the unpaved runway surface and an elevated density altitude (high humidity and mid-morning temperature in the 80's)? Yes, she got the wheels off at some point short of 3000 feet -- the takeoff video http://tighar.org/Projects/Earhart/ameliavideo.html (http://tighar.org/Projects/Earhart/ameliavideo.html) shows her rotating, lowering the nose, and accelerating in ground effect. But remaining runway is still a concern until the plane can start climbing out of ground effect. In this case, she wasn't able to climb until over the water.
LTM,
Mona
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I might have considered gassing up and leaving Fred behind. MHO
Or maybe she should have left behind all that heavy gold bullion. ;)
But then the large eel (snake) and its friends the squid, the octopi, and the sharks wouldn't have anything to guard! ;D
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For the takeoff at Lae the plane weighted about 14,000 pounds. 14,000/16,500 = 0.848 which squared equals 0.719 times 2100 feet means the takeoff at Lae should have taken 1,512 feet. Adding 243 pounds of fuel, and doing the same calculation results in a takeoff distance of 1,565 feet, only 53 feet longer, not much to worry about.
gl
Is your point that she should have considered 3000 feet plenty enough runway since the plane theoretically should have been able to get wheels off the ground in 1565 feet? And does that figure take into account the unpaved runway surface and an elevated density altitude (high humidity and mid-morning temperature in the 80's)?
LTM,
Mona
That estimate did account for the unpaved runway but did not account for the density altitude. I used the wrong weight, 14,000 pounds, her weight at Oakland. Her actual weight at Lae was probably only about 500 pounds more than at Oakland, she had about 150 gallons more fuel, weighing 900 pounds, but she was also short two people, Manning and Mantz, and their baggage, totaling about 400 pounds. So the weight was probably about 14,500 pounds but I will be conservative and overestimate the weight and use 15,000 for this calculation.
I have attached three years of data for 14 weather reporting stations in Papua New Guinea. This should be a representative sample and should validly predict the temperatures for 1937. Similar data would have been used in making the decision on whether more power was needed for the takeoff at Lae. The nearest reporting station to Lae is Nadzab located 22 SM inland from Lae. The highest July temperature recorded there during the three year period was 30.1 ° C (86 ° F. ) The temperature should be lower at Lae since it is located on the coast. A 30 ° C temperature at a sea level airport produces a density altitude of 2,000 feet which would increase the takeoff distance by only 6% from the sea level density takeoff performance. Lockheed report 487 states that a sea level takeoff takes 2,100 feet so increasing this by 6% would predict a takeoff at a 2,000 foot density altitude would take 2,226 feet, well short of the 3,000 feet available at Lae. But even this distance is based on a gross weight of 16,500 pounds and we know the plane actually weighed no more than 15,000 pounds at Lae. Takeoff performance varies with the weight ratio squared. Dividing 15,000 by 16,500 gives 0.909 which squared makes 0.826 which multiplied by 2,226 feet gives the predicted takeoff run at Lae at a gross weight of 15,000 pounds and at a two thousand foot density altitude of 1,840 feet giving a safety margin for takeoff at Lae of more than 1,160 feet, a 63% safety margin.
The runway was grass at Lae and not paved. Modern takeoff performance data is calculated for paved runways but Lockheed did the calculation for a turf runway since paved runways were a rarity in 1937. Page 2 of report 487 states that it takes 2,100 feet to take off "on a hard run-way" so I can see why you would think the calculation was for a paved runway. But look at page 21, where they go through the actual calculation, where is shows that the calculation was for "a good field with hard turf." The calculation uses a coefficient of friction ( μ, mu) of .04 for the calculation which is the μ for turf. The μ for pavement is .02, for short grass μ is .05 and it is .10 for tall grass. The coefficient of friction affects the takeoff roll because it retards the acceleration, the greater the μ the slower the acceleration. This retarding force gradually drops to zero as more and more of the weight of the plane is carried by the wings as speed increases. At the same time the drag due to increasing air resistance increases which slows down the acceleration as the plane approaches takeoff speed. All of these factors are accounted for on pages 21-23 which steps you through the calculation and you can redo the calculations yourself by substituting your chosen value for μ. If you don't want to go through the entire calculation you can use a rule of thumb to come up with a reasonable adjustment for longer grass at Lae. The rule of thumb is to increase the distance for takeoff from a paved runway ( μ = .02) by 7% for turf, 10% for short grass and 25% for tall grass. First back out the 7% for the turf runway that the calculation assumed and then apply the percent increase for different runway surfaces. But the runway at Lae was also described as "turf" and it looks like "turf" on the video, so the value calculated in report 487 should be applicable. At the worst, the runway is "short grass" and not "tall grass." Using the rule of thumb would increase the takeoff distance only 50 feet more for "short grass" rather than "turf."
If you want, you can also use these formulas for calculating the takeoff distance for different gross weights and for density altitude. If adjusting for gross weight you must first calculate the takeoff speed using the normal formula for lift. The takeoff speed also determines the dynamic pressure, "q", which you need for the takeoff formula and also is needed for determining the final thrust from the table on page 21.
If you want to do the calculation for a different density altitude then you again calculate the takeoff speed but you must substitute the density of the air at the altitude that interests you. ρ at sea level conditions is .002378 slugs per cubic foot but gets less at higher density altitudes. You also use the air density in the takeoff formula as the divisor under the gross weight. In this case it is used in the form of pounds per cubic foot. You can calculate this value by multiplying ρ by 32.17 pounds per slug conversion factor. The other number that shows up in the formula, "458" is the wing area and is a constant.
I don't know if you fly supercharged airplanes but density altitude is not the bugbear for takeoff of supercharged airplanes that it is for naturally aspirated airplanes. This is because there are two ways density altitude (another way of describing the density of the air, rho, that changes with actual height above sea level and with temperature) affects takeoff performance. The first effect is that the airplane must accelerate to a higher true airspeed in order for the indicated airspeed (and q, the dynamic pressure) to increase to the level that the wings can make enough lift for the plane to get off the ground. If the Electra at standard sea level conditions took off at 85 mph indicated airspeed which is also 85 mph true airspeed at zero density altitude, it would still takeoff at 85 mph indicated airspeed but the true airspeed at 2,000 foot density altitude would be 87 mph. It takes a bit longer to accelerate to 87 than it does to 85.This effect on takeoff is equal to the inverse of the density ratio. Air at standard sea level conditions, zero altitude and 59° F, has a density of .002378 slugs per cubic foot while air at standard temperature at 2,000 feet (a 2,000 foot density altitude) has a density of .002242 making the density ratio of .9428. One divided by .9428 equals 1.06 so the takeoff should take about 6% more runway than at a density altitude of sea level.
The second effect that the air density has on takeoff performance is that the power output of the engine also drops off as the air gets thinner so the engines produce less thrust which then reduces the rate of acceleration so it takes even longer for the plane to reach the higher true airspeed needed to takeoff at a density altitude above sea level. This is a problem for airplanes with naturally aspirated engines but is NOT a problem with supercharged engines below the critical altitude since these engines produce full sea level power up to the critical altitude. The type certificate data sheet for the S3H1 engine shows that the critical altitude for takeoff power of 600 horsepower is a 3,000 foot density altitude. This means that her S3H1 engines would produce full 600 hp takeoff power for the takeoff at Lae even if the temperature was 110 ° F but we know that it was no more than 86° F. The engines will also produce the 550 hp continuous rating up to a density altitude of 5,000.
Since these two effects parlay for an airplane with naturally aspirated engines, such a plane would use about 36% more runway at a 2,000 foot density altitude compared to zero density altitude. But since the Electra had supercharged engines and the density altitude did not exceed the critical altitude, the increase to the takeoff distance would be only the 6% previously mentioned.
And looking at the runway gradient, Long states that they had to taxi uphill to get to their starting position on the runway which would mean that they had a downhill gradient for takeoff which would help them and shorten the takeoff roll.
gl
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Gary,
I'm still not clear what your point is. The historical reality was that the plane used the full runway as reported by witnesses; you calculate that it should have or would have or could have needed less. So . . . . ?
LTM,
Mona
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Gary,
I'm still not clear what your point is. The historical reality was that the plane used the full runway as reported by witnesses; you calculate that it should have or would have or could have needed less. So . . . . ?
LTM,
Mona
The data available to the planners showed that there was a large safety margin for the takeoff at Lae. However, we know, after the fact, that the takeoff was anything but easy, it was what is technically known as a "hairy takeoff" and the plane barely got off the ground before the end of the 3,000 foot long runway. I can see how some might look at the actual takeoff and conclude that more power was needed from the engines or that the plane was terribly overloaded. Look at the the video of the takeoff, watch it a few times. (Notice that Noonan doesn't appear to be drunk.)
http://tighar.org/Projects/Earhart/ameliavideo.html
Then read the attached pages from Report 487.
Then watch the video again. Can you figure out why the takeoff used so much runway?
However, before the fact, the planners had no reason to suspect that it would be such a "hairy takeoff" so no reason to try to get more more power out of the engines.
gl
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Then read the attached pages from Report 487.
Hmm. That summary says nothing about how much distance to expect between takeoff and the point where the plane should be able to start climbing out of ground effect.
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Then read the attached pages from Report 487.
Hmm. That summary says nothing about how much distance to expect between takeoff and the point where the plane should be able to start climbing out of ground effect.
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Today "takeoff distance" is the distance from brake release until climbing to 50 feet but it is clear from report 487 that it meant "ground run", from brake release until the wheels come off the ground. Collopy said the wheels "had not left the ground" until 50 yards short of the end of the runway so the ground run was 2850 feet. Chatter said the "run" was 850 yards making the ground run 2550 feet. Either of these observations are significantly longer than the 1840 feet calculated from the information in report 487.
Didn't you notice anything else?
gl
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Didn't you notice anything else?
I note that the flaps don't appear to be extended, although it's hard to be sure because the images are so fuzzy. If they were indeed up, that raises the question of why she might not choose to use them despite the 30 degree recommendation in report 487. The answer may be in this excerpt from a letter Clarence Johnson wrote her during preparations for the world flight:
The use of 10 to 30 degrees of wingflap with takeoff power will reduce the takeoff run about 20%. If a normal, good runway is available, with a length of 3000 feet (for the heavier loads), no wingflap is required or recommended as the ship will take off in 2000 feet with a load of 14,000#. The greatest danger in using wingflaps on takeoff lies in the reduction of directional control at the beginning of the run, and in retracting the wingflaps after takeoff. (Pg. 44, Kelley: More Than My Share of It All)
--Mona
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Didn't you notice anything else?
I note that the flaps don't appear to be extended, although it's hard to be sure because the images are so fuzzy.
Maybe I have a clearer image but it is clear to me that the flaps were not set
to 30 degrees at the time of the takeoff in Lae. I am attaching two photos from
Purdue to help you evaluate the flap position in the takeoff video. The first
one shows the trailing edge of the right wing's top surface. (flap.jpg) Notice
there is no outline of the flap itself because the flaps on the Electra 10 are
split flaps, only the bottom surface of the wing deflects downward. The second
picture (flap down2.jpg) shows the left flap lowered, you can see it extending
downward from the bottom surface of the wing. The outboard edge of the flap is
aligned with the "1" in the registration number painted on the bottom of the
left wing. Note how the split flap looks. Since the flap surface is separated
from the top surface of the wing, this creates a thick dark area as seen from
behind due to the upper surface of the wing staying fixed and the bottom
surface, the flap, splitting and deflecting downward.
I couldn't find an actual photo of an Electra 10 in flight with the flaps down.
I did find a you tube video showing a computer animated landing of the plane
which does show clearly what the flaps look like when they are lowered. This
animation looks to be accurate and looks like some of the computer animated
trial exhibits prepared for me by accident reconstructionists trial experts.
Look at this video and then look at the takeoff video again and I think you will
be convinced that the flaps were not extended for the Lae takeoff.
http://www.youtube.com/watch?v=zk2rjEDtjdM&feature=related (http://www.youtube.com/watch?v=zk2rjEDtjdM&feature=related)
-------------------------------------------------------------------------------------------
ADDED:
Here is a link to an Electra flying by with the flaps both up and down, (http://www.youtube.com/watch?v=halcPvrj-hI&feature=related) it is easy to detect the difference.
----------------------------------------------------------------------------------------------
If they were indeed up, that raises the question of why she might not choose to use them despite the 30 degree recommendation in report 487. The answer may be in this excerpt from a letter Clarence Johnson wrote her during preparations for the world flight:
The use of 10 to 30 degrees of wingflap with takeoff power will reduce the takeoff run about 20%. If a normal, good runway is available, with a length of 3000 feet (for the heavier loads), no wingflap is required or recommended as the ship will take off in 2000 feet with a load of 14,000#. The greatest danger in using wingflaps on takeoff lies in the reduction of directional control at the beginning of the run, and in retracting the wingflaps after takeoff. (Pg. 44, Kelley: More Than My Share of It All)
--Mona
Or she simply forgot. Either way, following the procedure in report 487 would have shaved about 500 feet off the takeoff roll and so it would not have been nearly as hair raising for the observers and for the people in the plane and would not have provided ammunition for those who speculate about engine switches, spy missions or gold bullion smuggling.
Before anybody accuses me of being critical of the flying abilities of Earhart or of women pilots in general, I must point out that these types of accidents happen all the time, almost always involving male pilots. A quick check of the NTSB website shows two FATAL accidents in 2009 alone caused by attempting to take off from a short runway without properly setting the flaps for a short field takeoff.
http://dms.ntsb.gov/aviation/AccidentReports/o1p0cgqeqsuxb5555aopug551/D12012011120000.pdf (http://dms.ntsb.gov/aviation/AccidentReports/o1p0cgqeqsuxb5555aopug551/D12012011120000.pdf)
http://dms.ntsb.gov/aviation/AccidentReports/14mmym55xqfv2q55eznk1d551/X12012011120000.pdf (http://dms.ntsb.gov/aviation/AccidentReports/14mmym55xqfv2q55eznk1d551/X12012011120000.pdf)
gl
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I agree, this is an interesting catch and a neat explanation for the long run. Seems like the question of whether to use flaps for the Lae takeoff may have been a tough call -- Minimize the takeoff run at the cost of some directional control? Or maximize directional control at the cost of some extra takeoff distance? I think I too might choose the latter if I'd recently experienced a groundloop.
LTM,
Mona
-
If they were indeed up, that raises the question of why she might not choose to use them despite the 30 degree recommendation in report 487. The answer may be in this excerpt from a letter Clarence Johnson wrote her during preparations for the world flight:
The use of 10 to 30 degrees of wingflap with takeoff power will reduce the takeoff run about 20%. If a normal, good runway is available, with a length of 3000 feet (for the heavier loads), no wingflap is required or recommended as the ship will take off in 2000 feet with a load of 14,000#. The greatest danger in using wingflaps on takeoff lies in the reduction of directional control at the beginning of the run, and in retracting the wingflaps after takeoff. (Pg. 44, Kelley: More Than My Share of It All)
--Mona
Or she simply forgot. Either way, following the procedure in report 487 would have shaved about 500 feet off the takeoff roll and so it would not have been nearly as hair raising for the observers and for the people in the plane and would not have provided ammunition for those who speculate about engine switches, spy missions or gold bullion smuggling.
gl
What Johnson said was correct for a 14,000 pound takeoff without flaps but was definitely NOT TRUE for a 15,000 pound takeoff which takes significantly more than 2,000 feet at standard conditions and even more at the 2,000 foot density altitude at Lae. According to report 487, it takes 2,600 feet to take off without flaps at 16,500 pounds at a sea level density altitude. Doing the same calculations we did before, we find that a takeoff at Lae at a density altitude of 2,000 feet and 15,000 pounds without flaps results in a ground run of 2,278 feet. Lest you think that this is all just theoretical mumbo-jumbo, this calculation agrees quite closely with Chatter's observation of 2,550 feet, a difference of only 272 feet, less than a 12% difference thus Chatter's observation confirms the accuracy of this calculation. (I accept Chatter's report as more accurate in all of it's detail compared to Collopy's short letter.)
It is interesting to look at what would have happened if Earhart had completely filled that tank, adding about 50 U.S. gallons weighing 300 pounds. A takeoff at 15,300 pounds without flaps would have taken 2,370 feet, only 92 feet longer. And if she had put the flaps down to the 30° position specified in report 487 the takeoff would have taken only 1,914 feet providing a 1,086 foot safety margin, 57% extra runway.
We know that Earhart did not fill that tank because she believed that she needed 100 octane fuel to get maximum power out of her engines but Pratt and Whitney documents show that the engines make full takeoff power of 600 horsepower using the 87 octane fuel available at Lae (Jeff Neville disputes this) so she could have filled that tank, made a safe takeoff, and then have an extra hour of flying endurance to find a safe place to land.
Just for the sake of argument, let's say that Neville is correct and that she could only get 550 horsepower from each engine using 87 octane fuel, how would this have affected the takeoff? The length of the takeoff run varies with the inverse of the ratio of the engine power. Report 487 shows 2,100 feet for standard conditions, 30° of flaps, and 16,500 pounds using the full power of 600 horsepower from each engine, a total of 1,200 horsepower so taking off with a total of 1,100 hp gives a takeoff distance 9% longer, 2,290 feet. We adjust this for the takeoff weight of 15,300 pounds as we did before and find 1,970 feet. We then increase this by 6% to account for the density altitude so the complete calculation gives 2,088 feet compared to 1,914 for 1,200 hp (we could have just multiplied the 1,914 by 1.09 too), only 174 feet longer and with 912 foot safety margin, 44% extra runway available. Doing the same calculation for the flaps up scenario produces a takeoff run of 2,585 but this would be cutting it close so Earhart would have to have remembered to set the flaps correctly.
So no matter how you figure it, Earhart unnecessarily left behind an hour's worth of fuel and this fuel could have made a significant difference in the end.
gl
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There is now incontrovertible proof that the plane did NOT land on Nikumororo. NBC news reported that the Airworthiness Certificate for the airplane was just discovered in California and that this Airworthiness Certificate must be carried in the plane at all times, so this means that the plane was secretly brought back to the U.S. and then disposed of. Since the plane made it back to the U.S. it could not possibly be found on Niku.
(chuckle)
Obviously the plane never left California by air. I well remember my ground school instructor explaining that it wasn't horsepower, nor aerodynamics, nor even Bournoulli's principal that enabled an airplane to fly, it was the airworthiness certificate. Without it, an airplane could not fly, and that was that!
Hmmm....I suspect your ground instructor must have been ex-military (those military guys tend to lead a sheltered existence and do not always get to see the whole picture) as it seems he is in need of a little refresher training.
For ANY pilot will tell you, without any hesitation or reservation of any sort, that there is one thing and only one thing that EVER makes an airplane fly......
....MONEY!!! ;D ;D
LTM,
....twb
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I note that the flaps don't appear to be extended, although it's hard to be sure because the images are so fuzzy.
--Mona
Here is a link to an Electra flying by with the flaps both up and down, it is easy to detect the difference.
http://www.youtube.com/watch?v=halcPvrj-hI&feature=related
gl
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There is now incontrovertible proof that the plane did NOT land on Nikumororo. NBC news reported that the Airworthiness Certificate for the airplane was just discovered in California and that this Airworthiness Certificate must be carried in the plane at all times, so this means that the plane was secretly brought back to the U.S. and then disposed of. Since the plane made it back to the U.S. it could not possibly be found on Niku.
(chuckle)
Obviously the plane never left California by air. I well remember my ground school instructor explaining that it wasn't horsepower, nor aerodynamics, nor even Bournoulli's principal that enabled an airplane to fly, it was the airworthiness certificate. Without it, an airplane could not fly, and that was that!
Hmmm....I suspect your ground instructor must have been ex-military (those military guys tend to lead a sheltered existence and do not always get to see the whole picture) as it seems he is in need of a little refresher training.
For ANY pilot will tell you, without any hesitation or reservation of any sort, that there is one thing and only one thing that EVER makes an airplane fly......
....MONEY!!! ;D ;D
LTM,
....twb
Similarly, it is not the elevator nor the throttle that controls altitude. Altitude is actually controlled by oil pressure, when the oil pressure goes down to zero, the plane goes down to zero altitude.
gl
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In the video, she appears to have 0 flaps, pulled hard off in ground affect, leveled off in ground affect to gain speed. And she would have lost ground affect going over the cliff causing the drop down to the sea to avoid stalling.
Just a 'hot and heavy' takeoff on a soft field.
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Similarly, it is not the elevator nor the throttle that controls altitude. Altitude is actually controlled by oil pressure, when the oil pressure goes down to zero, the plane goes down to zero altitude.
gl
Second that -
And the propeller's true purpose is to keep the pilot cool; watch the pilot sweat when it quits...
LTM -
I don't know if the guy was sweating, but listen to his breathing. Due to the lack of chat, I'd also assumed he was solo until it was on the ground! Sensible passenger - let him concentrate.
http://www.youtube.com/watch?v=t0txEC0Rhdg (http://www.youtube.com/watch?v=t0txEC0Rhdg)
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I think Jeff is being more thoughtful in his reply #41 on page 3 of this thread. It's likely AE did not want to dilute her 100 octane believing she needed it for her take off at Howland. She didn't plan to get lost. She did have to plan on taking off from a newly constructed airfield on a very small island she had never been to before. No 100 octane on Lae to top up with? Okay so she saves what she has of the fuel she believes will "boost" her takeoff for Howland. AE at this point is still planning to finish the trip. Perhaps as Jeff observes, the discussion needs to be more practical and less technically oriented. Think in terms of AE and her planning the trip. Who said she planned on using the 100 octane for the takeoff at Lae where she knew exactly what runway length and condition were?
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I think Jeff is being more thoughtful in his reply #41 on page 3 of this thread. It's likely AE did not want to dilute her 100 octane believing she needed it for her take off at Howland. She didn't plan to get lost. She did have to plan on taking off from a newly constructed airfield on a very small island she had never been to before. No 100 octane on Lae to top up with? Okay so she saves what she has of the fuel she believes will "boost" her takeoff for Howland. AE at this point is still planning to finish the trip. Perhaps as Jeff observes, the discussion needs to be more practical and less technically oriented. Think in terms of AE and her planning the trip. Who said she planned on using the 100 octane for the takeoff at Lae where she knew exactly what runway length and condition were?
The runway was longer at Howland.
gl
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But the field was an unpaved, untested airfield on a very small island. AE knew there were no facilities there other than what Itasca would have. If she believed 100 octane would give her take off a boost, from a brand new unpaved runway that no aircraft had ever landed on or taken off from, then wouldn't she want to save the 100 octane for that takeoff? Use all the runway at Lae with her regular fuel, believing she had ample fuel and reserve to make it to Howland. This, of course, is all theory as she never made it to Howland or radioed to say what she was planning. I ask the pilots out there.... If you were doing this trip, and using the knowledge of 1937, what would you do? Could you, or would you, trust that the Howland airfield was built as advertised?
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But the field was an unpaved, untested airfield on a very small island. AE knew there were no facilities there other than what Itasca would have. If she believed 100 octane would give her take off a boost, from a brand new unpaved runway that no aircraft had ever landed on or taken off from, then wouldn't she want to save the 100 octane for that takeoff? Use all the runway at Lae with her regular fuel, believing she had ample fuel and reserve to make it to Howland. This, of course, is all theory as she never made it to Howland or radioed to say what she was planning. I ask the pilots out there.... If you were doing this trip, and using the knowledge of 1937, what would you do? Could you, or would you, trust that the Howland airfield was built as advertised?
Yes, based on all the high level government support for the mission including that from the White House and Earhart's personal friendship with Elanor Roosevelt.
gl
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Well Gary, you seem to have an answer for everything. AE an FN must have landed on Howland. Apparently any idea put forth that suggests otherwise is clearly wrong based on your evidence. In all honesty I know you don't believe that but as I said in this forum before "something didn't go as planned because they didn't get there.". Wonder what it was. Hmm.
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Could you, or would you, trust that the Howland airfield was built as advertised?
Yes, based on all the high level government support for the mission including that from the White House and Earhart's personal friendship with Elanor Roosevelt.
gl
This seems like a pretty weak argument. The Roosevelts didn't personally build or oversee construction of the airfield. It was constructed in a remote part of the world by a small and largely untrained workforce. I would not be surprised if Earhart had some concerns about how prepared the site really was to accommodate her needs.
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Could you, or would you, trust that the Howland airfield was built as advertised?
Yes, based on all the high level government support for the mission including that from the White House and Earhart's personal friendship with Elanor Roosevelt.
gl
This seems like a pretty weak argument. The Roosevelts didn't personally build or oversee construction of the airfield. It was constructed in a remote part of the world by a small and largely untrained workforce. I would not be surprised if Earhart had some concerns about how prepared the site really was to accommodate her needs.
I guess you've have never heard of "command emphasis." If the influence from the White House seems too attenuated to you, consider then that Earhart's good friend, former business partner, and, some claim, her lover, Gene Vidal was Director of the Bureau of Air Commerce (like the head of the FAA today) and the airport at Howland was built by his Bureau and Richard Black, on site, was employed by the Bureau. To put it another way, if you were a worker bee driving a bulldozer on Howland and you know that this airport was directly ordered by Vidal and that Earhart hung out at the White House, how secure would you think your job would be if you didn't get the runway built on time? And the original arrival date was March 20, 1937, three and a half months earlier than the actual arrival date and the runways had to be completed by that earlier date.
I think that Earhart could be pretty confident that the airport would be waiting for her.
gl
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Sorry Gary
It is likely that the worker bees knew nothing of Vidal or of Earhart hanging out at the white house. The labour was mostly native. Some guys hired for a contract and managed by some Americans. I'm pretty sure there wasn't a lot of discussion around the campfire at night about Earhart's social hold on Mrs Roosevelt and the politics of Washington.
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... the original arrival date was March 20, 1937, three and a half months earlier than the actual arrival date and the runways had to be completed by that earlier date.
I think that Earhart could be pretty confident that the airport would be waiting for her.
Agreed.
A fairly detailed account of the construction of Kamakaiwi Field is given in Finding Amelia (http://tighar.org/wiki/Finding_Amelia). That story concludes:
"At long last, on Saturday, March 13, 1937, a message arrived from
Campbell on Howland with apologies that static interference had precluded
communication for the past three days. Two runways had been completed:
the 2400-foot east–west strip and the 3000-foot northeast–southwest strip.
To accommodate Earhart’s expressed desire for 'as long a runway as
possible for takeoff,' the north–south strip would now be nearly a full
mile long. Campbell promised that it would be finished by March 15.
"Richard Black announced that the airport had been officially named
Kamakaiwi Field in honor of James Kamakaiwi, the Honolulu boy who
had been the first Hawaiian to go ashore on Howland when the island
was first colonized on March 30, 1935, and had been the leader of the
colonists ever since." (FA, 17-18).
William T. Miller (http://tighar.org/wiki/Miller) was the Bureau of Air Commerce employee selected to head colonization of Jarvis (http://en.wikipedia.org/wiki/Jarvis_Island), Baker (http://en.wikipedia.org/wiki/Baker_Island), and Howland Island (http://tighar.org/smf/../wiki/Howland_Island) (the American Equatorial Islands (http://tighar.org/smf/../wiki/American_Equatorial_Islands)).
He was the coordinator for the first attempt to land on Howland. He was someone whom Earhart trusted, and he seems to have been worthy of trust. I have not read the whole of his correspondence with Earhart and Putnam (https://public.me.com/hankdavison). Ric and Pat created a chronological index (http://tighar.org/aw/mediawiki/images/7/74/WT_Miller_Chronological_Files_Index_Rev_1.pdf) to the correspondence that gives some idea of how they were kept informed on progress.
The thought that Earhart might have been anxious about the newly-prepared airstrip is undocumented. It is a mere logical possibility derived from thinking in the abstract rather than surveying the available data. The argument, such as it is, is based on the proponent's imagination about what Earhart would have thought and consequently what she would have done, if that mental reconstruction of her ideas is correct. Such arguments from imaginary premises are moot (http://tighar.org/wiki/Moot)--possibly true, endlessly arguable, and ultimately irrelevant. We can read the actual correspondence that has turned up to date and we can remember that she took off for Howland from Lae on the morning of 2 July 1937. It may be true that anxieties about the Howland airfield affected her decision about the 100-octane tank; it may be false.
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Sorry Gary
It is likely that the worker bees knew nothing of Vidal or of Earhart hanging out at the white house. The labour was mostly native. Some guys hired for a contract and managed by some Americans. I'm pretty sure there wasn't a lot of discussion around the campfire at night about Earhart's social hold on Mrs Roosevelt and the politics of Washington.
There were, and are, no "natives" on Howland Island, everybody was brought from Hawaii.
hl
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Sorry Gary
It is likely that the worker bees knew nothing of Vidal or of Earhart hanging out at the white house. The labour was mostly native. Some guys hired for a contract and managed by some Americans. I'm pretty sure there wasn't a lot of discussion around the campfire at night about Earhart's social hold on Mrs Roosevelt and the politics of Washington.
There were, and are, no "natives" on Howland Island, everybody was brought from Hawaii.
gl
True. The first chapter of Finding Amelia (http://tighar.org/wiki/FA), which tells the story of the colonization and the building of the airfield, is in ''TIGHAR Tracks'' volume 21, 2005, pp. 10-22. (http://tighar.org/Publications/TTracks/2005Vol_21/2101.pdf)
Pictures of the Howland Island colonists in this thread (http://tighar.org/smf/index.php/topic,493.msg6150.html#msg6150).
I may be hallucinating, but I seem to remember reading the story of the construction of the airstrip from a diary of one of the colonists. I haven't been able to turn up the reference, if it exists.
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James Kamakaiwi' Journal (http://tighar.org/Projects/Earhart/Archives/Documents/Reports/Kamakaiwi.pdf) you're thinking of, I imagine. It was very interesting.
Rick
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Additional portions of the James Kamakaiwi Journal are here (http://tighar.org/Projects/Earhart/Archives/Documents/Reports/BlackCruise.pdf), and a very interesting account of the Japanese attack on Howland (http://kapalama.ksbe.edu/archives/historical/huipanalaau/end.php) is here.
Rick J
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James Kamakaiwi's Journal (http://tighar.org/Projects/Earhart/Archives/Documents/Reports/Kamakaiwi.pdf) you're thinking of, I imagine. It was very interesting.
Yes, I looked at that several times today.
But it doesn't cover the period of constructing the runways in 1936-1937. It may be that I have the Howland crew mixed up with some other group building runways on another of the Equatorial or Phoenix Islands ... or I am just straight-up wrong about my recollection.
-
Sorry Gary
It is likely that the worker bees knew nothing of Vidal or of Earhart hanging out at the white house. The labour was mostly native. Some guys hired for a contract and managed by some Americans. I'm pretty sure there wasn't a lot of discussion around the campfire at night about Earhart's social hold on Mrs Roosevelt and the politics of Washington.
There were, and are, no "natives" on Howland Island, everybody was brought from Hawaii.
hl
I actually knew that and my use of the word "natives" was misleading. I had meant native in the sense of local (Hawaian) and not from somewhere like the army engineer corp.
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... the original arrival date was March 20, 1937, three and a half months earlier than the actual arrival date and the runways had to be completed by that earlier date.
I think that Earhart could be pretty confident that the airport would be waiting for her.
Agreed.
A fairly detailed account of the construction of Kamakaiwi Field is given in Finding Amelia (http://tighar.org/wiki/Finding_Amelia). That story concludes:
"At long last, on Saturday, March 13, 1937, a message arrived from
Campbell on Howland with apologies that static interference had precluded
communication for the past three days. Two runways had been completed:
the 2400-foot east–west strip and the 3000-foot northeast–southwest strip.
To accommodate Earhart’s expressed desire for 'as long a runway as
possible for takeoff,' the north–south strip would now be nearly a full
mile long. Campbell promised that it would be finished by March 15.
"Richard Black announced that the airport had been officially named
Kamakaiwi Field in honor of James Kamakaiwi, the Honolulu boy who
had been the first Hawaiian to go ashore on Howland when the island
was first colonized on March 30, 1935, and had been the leader of the
colonists ever since." (FA, 17-18).
William T. Miller (http://tighar.org/wiki/Miller) was the Bureau of Air Commerce employee selected to head colonization of Jarvis (http://en.wikipedia.org/wiki/Jarvis_Island), Baker (http://en.wikipedia.org/wiki/Baker_Island), and Howland Island (http://tighar.org/smf/../wiki/Howland_Island) (the American Equatorial Islands (http://tighar.org/smf/../wiki/American_Equatorial_Islands)).
He was the coordinator for the first attempt to land on Howland. He was someone whom Earhart trusted, and he seems to have been worthy of trust. I have not read the whole of his correspondence with Earhart and Putnam (https://public.me.com/hankdavison). Ric and Pat created a chronological index (http://tighar.org/aw/mediawiki/images/7/74/WT_Miller_Chronological_Files_Index_Rev_1.pdf) to the correspondence that gives some idea of how they were kept informed on progress.
The thought that Earhart might have been anxious about the newly-prepared airstrip is undocumented. It is a mere logical possibility derived from thinking in the abstract rather than surveying the available data. The argument, such as it is, is based on the proponent's imagination about what Earhart would have thought and consequently what she would have done, if that mental reconstruction of her ideas is correct. Such arguments from imaginary premises are moot (http://tighar.org/wiki/Moot)--possibly true, endlessly arguable, and ultimately irrelevant. We can read the actual correspondence that has turned up to date and we can remember that she took off for Howland from Lae on the morning of 2 July 1937. It may be true that anxieties about the Howland airfield affected her decision about the 100-octane tank; it may be false.
The condition of the new airfield at Howland was not the best funded or organized project. While AE's friends in Washington DC wanted an airfield built it was certainly not something undertaken by a group like the Army Engineering corp. in fact it's lucky to have been built at all. See TIGHAR's own documents at http://tighar.org/Publications/TTracks/2005Vol_21/2101.pdf (http://tighar.org/Publications/TTracks/2005Vol_21/2101.pdf). Page 14. In fact it was constructed with a rebuilt bull dozer that was used with native Hawaian labour.
While AE would not likely have known how the airport was being built she did know it was being built at her request and had no idea what it be like. She had no experienced pilots to talk to about this airport because it didn't exist yet. In fact read pages 15 thru 17 on how this airfield was built. I don't think AE was expecting asphalt runways and a terminal building but she knew it was just being completed for her. Your reply above Marty even states that AE requested 'as long a runway as possible for takeoff,'. She didn't know how long they were.
The idea I floated that she may have been anxious on the state of the airfield is based on these TIGHAR reported facts. Is it arguable that she may have been anxious about this brand new airfield? Yes. But how many of you pilots out there would take off for a mid ocean airfield just constructed at your request that no one had ever landed on and you know nothing about?? And it's near the end of your normal fuel load and no nearby airports as alternates? Is it LIKELY she was anxious? True or false?
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Your reply above Marty even states that AE requested 'as long a runway as possible for takeoff,'. She didn't know how long they were.
What is says is that the people in charge of building her the runway reported the existing and planned lengths to her on March 13.
I don't see how you turn that piece of information that she had been told about the length of the runways into the belief that she did not know the length of the runways.
The idea I floated that she may have been anxious on the state of the airfield is based on these TIGHAR reported facts.
The "reported fact" is that she was told how long the runways were.
What is not a "reported fact" is your surmise that "she may have been anxious" about the airfield.
Maybe she was.
Maybe she wasn't.
She took of from Lae on 2 July 1937, planning to use the airfield for a landing and takeoff.
Is it arguable that she may have been anxious about this brand new airfield? Yes. But how many of you pilots out there would take off for a mid ocean airfield just constructed at your request that no one had ever landed on and you know nothing about?? And it's near the end of your normal fuel load and no nearby airports as alternates? Is it LIKELY she was anxious? True or false?
I don't know. I never met her in person. Feelings are funny things. They are deeply personal. Different people react differently from other people. I understand that you are convinced that you have a rock-solid fact in your possession, based on what you imagine she would have felt. I don't respect that piece of imaginary "evidence." I look at the takeoff as evidence that she judged the Howland runways as serviceable for her purposes.
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... the original arrival date was March 20, 1937, three and a half months earlier than the actual arrival date and the runways had to be completed by that earlier date.
I think that Earhart could be pretty confident that the airport would be waiting for her.
The condition of the new airfield at Howland was not the best funded or organized project. While AE's friends in Washington DC wanted an airfield built it was certainly not something undertaken by a group like the Army Engineering corp. in fact it's lucky to have been built at all.
It's actually the Army Corps of Engineers.
gl
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... the original arrival date was March 20, 1937, three and a half months earlier than the actual arrival date and the runways had to be completed by that earlier date.
I think that Earhart could be pretty confident that the airport would be waiting for her.
The idea I floated that she may have been anxious on the state of the airfield is based on these TIGHAR reported facts. Is it arguable that she may have been anxious about this brand new airfield? Yes. But how many of you pilots out there would take off for a mid ocean airfield just constructed at your request that no one had ever landed on and you know nothing about?? And it's near the end of your normal fuel load and no nearby airports as alternates? Is it LIKELY she was anxious? True or false?
I remember flying across the Atlantic in a single engine airplane looking for the mid ocean airfield on Santa Maria Island when the thought ran through my head, "Kid, you are taking it on faith that the guy that drew this chart wasn't just playing a practical joke and that the island is really where it is plotted on the chart." Then, just as quickly, I realized that the chart was drawn by grown-ups who took their responsibilities seriously, knowing that peoples' lives depended on the care they took in doing their work and "that was that," that first thought never crossed my mind again. And the island was there, just where it was supposed to be.
Earhart also knew that grown-ups were in charge of building the airport on Howland so I don't see any reason for her to have had any anxieties on that score.
gl
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... the original arrival date was March 20, 1937, three and a half months earlier than the actual arrival date and the runways had to be completed by that earlier date.
I think that Earhart could be pretty confident that the airport would be waiting for her.
The idea I floated that she may have been anxious on the state of the airfield is based on these TIGHAR reported facts. Is it arguable that she may have been anxious about this brand new airfield? Yes. But how many of you pilots out there would take off for a mid ocean airfield just constructed at your request that no one had ever landed on and you know nothing about?? And it's near the end of your normal fuel load and no nearby airports as alternates? Is it LIKELY she was anxious? True or false?
I remember flying across the Atlantic in a single engine airplane looking for the mid ocean airfield on Santa Maria Island when the thought ran through my head, "Kid, you are taking it on faith that the guy that drew this chart wasn't just playing a practical joke and that the island is really where it is plotted on the chart." Then, just as quickly, I realized that the chart was drawn by grown-ups who took their responsibilities seriously, knowing that peoples' lives depended on the care they took in doing their work and "that was that," that first thought never crossed my mind again. And the island was there, just where it was supposed to be.
Earhart also knew that grown-ups were in charge of building the airport on Howland so I don't see any reason for her to have had any anxieties on that score.
gl
Yes Gary. I am sure grown ups were involved in all aspects of AE's flight. However she didn't make it so some grown up made a mistake somewhere.
Grown ups make mistakes. In terms of navigation look at this one. http://tighar.org/wiki/Howland_Island#Correct_location_of_Howland_Island_known_in_1937 (http://tighar.org/wiki/Howland_Island#Correct_location_of_Howland_Island_known_in_1937). One year before Amelia's flight Itasca discovered Howland Island was charted wrong. Now don't get me wrong here. I recognize that AE and FN had the correct charts. I raise this as an example of grown ups being well intended but still getting it wrong.
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Your reply above Marty even states that AE requested 'as long a runway as possible for takeoff,'. She didn't know how long they were.
What is says is that the people in charge of building her the runway reported the existing and planned lengths to her on March 13.
I don't see how you turn that piece of information that she had been told about the length of the runways into the belief that she did not know the length of the runways.
The idea I floated that she may have been anxious on the state of the airfield is based on these TIGHAR reported facts.
The "reported fact" is that she was told how long the runways were.
What is not a "reported fact" is your surmise that "she may have been anxious" about the airfield.
Maybe she was.
Maybe she wasn't.
She took of from Lae on 2 July 1937, planning to use the airfield for a landing and takeoff.
Is it arguable that she may have been anxious about this brand new airfield? Yes. But how many of you pilots out there would take off for a mid ocean airfield just constructed at your request that no one had ever landed on and you know nothing about?? And it's near the end of your normal fuel load and no nearby airports as alternates? Is it LIKELY she was anxious? True or false?
I don't know. I never met her in person. Feelings are funny things. They are deeply personal. Different people react differently from other people. I understand that you are convinced that you have a rock-solid fact in your possession, based on what you imagine she would have felt. I don't respect that piece of imaginary "evidence." I look at the takeoff as evidence that she judged the Howland runways as serviceable for her purposes.
Thanks Marty. I originally floated the idea that she might have been anxious in another thread re 100 Octane fuel where I commented on a jpg copy of a telegram sent to Lae on June 25, 1937. The image came from Gary. It is here at http://tighar.org/smf/index.php?action=dlattach;topic=528.0;attach=431 (http://tighar.org/smf/index.php?action=dlattach;topic=528.0;attach=431). This, to me, says there are three runways. One at 4100 feet, second at 2600 feet and a third at 2250 feet. It then says a 300 foot, 50 feet wide, extension is being added to the west end of the east west runway for a total of 2750 feet. Now, at the risk of embarrassing myself if my math is wrong, I raise the fact that you can't add 300 to any of those runway lengths and get a runway length of 2750 feet! 4400, 2900 or 2550. I believe the extension is being made to the runway most likely to be used due to the prevailing winds. So is it 2250 being extended to 2550 or 2700 or what? More importantly is someone on the construction crew measuring correctly? Who is doing the math? It's grown ups Gary. Why isn't AE questioning this if she got it?
I also believe that just because information was sent AE didn't necessarily get it. You report Marty that she got the info in March. Yet she is asking for runway lengths in June. There are many examples of info requested and not received. Good intentions all by grown ups. Examples of poor communications abound.
Marty I do NOT believe I have solid evidence but I continue to say in this forum that you MUST read between the known "facts" and get into their heads. For some reason AE and FN did not make Howland. We don't know what happened. TIGHAR has a hypothesis. A good one in my opinion. I believe you have many of the available facts at hand and yet it's inconclusive. Many of the forum readers and contributors are pilots. These people have first hand knowledge of flying and are the best at getting into the pilots seat with Amelia and going through the motions of flying from Lae to Howland. From what I read they don't know what happened. Theories, supposition, guesses, and "I think"'s but no answer to what happened. So get out of the seat and into their heads. 1937 heads. What would AE say if she read that June telegram? Would she have said "holy smoke. The guys building this runway can't even do math correctly.".
I know this is infinitely arguable because we have no facts on it. But in the absence of direct facts, what is "likely" to have happened?
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... the original arrival date was March 20, 1937, three and a half months earlier than the actual arrival date and the runways had to be completed by that earlier date.
I think that Earhart could be pretty confident that the airport would be waiting for her.
The idea I floated that she may have been anxious on the state of the airfield is based on these TIGHAR reported facts. Is it arguable that she may have been anxious about this brand new airfield? Yes. But how many of you pilots out there would take off for a mid ocean airfield just constructed at your request that no one had ever landed on and you know nothing about?? And it's near the end of your normal fuel load and no nearby airports as alternates? Is it LIKELY she was anxious? True or false?
I remember flying across the Atlantic in a single engine airplane looking for the mid ocean airfield on Santa Maria Island when the thought ran through my head, "Kid, you are taking it on faith that the guy that drew this chart wasn't just playing a practical joke and that the island is really where it is plotted on the chart." Then, just as quickly, I realized that the chart was drawn by grown-ups who took their responsibilities seriously, knowing that peoples' lives depended on the care they took in doing their work and "that was that," that first thought never crossed my mind again. And the island was there, just where it was supposed to be.
Earhart also knew that grown-ups were in charge of building the airport on Howland so I don't see any reason for her to have had any anxieties on that score.
gl
Btw If you look at Gary's takeoff calculations below you see that a runway of 2250, 2550 or even 2700 is cutting it mighty fine if she is using the east west runway. The one with the prevailing winds. If she had the same info as Gary then wouldn't AE be "anxious" about that airfield? The same woman who ground looped a fully loaded Electra in Hawaii on a runway with "known" conditions?
"What Johnson said was correct for a 14,000 pound takeoff without flaps but was definitely NOT TRUE for a 15,000 pound takeoff which takes significantly more than 2,000 feet at standard conditions and even more at the 2,000 foot density altitude at Lae. According to report 487, it takes 2,600 feet to take off without flaps at 16,500 pounds at a sea level density altitude. Doing the same calculations we did before, we find that a takeoff at Lae at a density altitude of 2,000 feet and 15,000 pounds without flaps results in a ground run of 2,278 feet. Lest you think that this is all just theoretical mumbo-jumbo, this calculation agrees quite closely with Chatter's observation of 2,550 feet, a difference of only 272 feet, less than a 12% difference thus Chatter's observation confirms the accuracy of this calculation. (I accept Chatter's report as more accurate in all of it's detail compared to Collopy's short letter.)
It is interesting to look at what would have happened if Earhart had completely filled that tank, adding about 50 U.S. gallons weighing 300 pounds. A takeoff at 15,300 pounds without flaps would have taken 2,370 feet, only 92 feet longer. And if she had put the flaps down to the 30° position specified in report 487 the takeoff would have taken only 1,914 feet providing a 1,086 foot safety margin, 57% extra runway.
We know that Earhart did not fill that tank because she believed that she needed 100 octane fuel to get maximum power out of her engines but Pratt and Whitney documents show that the engines make full takeoff power of 600 horsepower using the 87 octane fuel available at Lae (Jeff Neville disputes this) so she could have filled that tank, made a safe takeoff, and then have an extra hour of flying endurance to find a safe place to land.
Just for the sake of argument, let's say that Neville is correct and that she could only get 550 horsepower from each engine using 87 octane fuel, how would this have affected the takeoff? The length of the takeoff run varies with the inverse of the ratio of the engine power. Report 487 shows 2,100 feet for standard conditions, 30° of flaps, and 16,500 pounds using the full power of 600 horsepower from each engine, a total of 1,200 horsepower so taking off with a total of 1,100 hp gives a takeoff distance 9% longer, 2,290 feet. We adjust this for the takeoff weight of 15,300 pounds as we did before and find 1,970 feet. We then increase this by 6% to account for the density altitude so the complete calculation gives 2,088 feet compared to 1,914 for 1,200 hp (we could have just multiplied the 1,914 by 1.09 too), only 174 feet longer and with 912 foot safety margin, 44% extra runway available. Doing the same calculation for the flaps up scenario produces a takeoff run of 2,585 but this would be cutting it close so Earhart would have to have remembered to set the flaps correctly.
So no matter how you figure it, Earhart unnecessarily left behind an hour's worth of fuel and this fuel could have made a significant difference in the end. ".
From the thread In Aircraft and power plant, Octane Analysis, reply 44. I'm not sure which runway he is suggesting she is using but the one I highlighted at the top adds up to a 3000 foot length and the closest to that is the reported 2900 foot runway. See runway lengths in http://tighar.org/smf/index.php?action=dlattach;topic=528.0;attach=431 (http://tighar.org/smf/index.php?action=dlattach;topic=528.0;attach=431) supplied by Gary in Octane analysis. Did I get my facts wrong here or is there a math problem?
Not being a pilot means I am ignorant of certain facts so I trust people like Gary to set me straight. I apologize in advance if I'm getting something wrong here or being seemingly misleading.
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And one last point on this airfield on Howland. Look here http://tighar.org/Projects/Earhart/Archives/Documents/Reports/BlackCruise.pdf (http://tighar.org/Projects/Earhart/Archives/Documents/Reports/BlackCruise.pdf). Look under the heading "June 26 and June 27". Pretty clear that the report, written by Richard Black himself, indicates that the 300 foot extension was finished in time for AE to arrive. But it's a thin layer of gravel over soft sand and only to be used for Take off as its deemed unsafe for landing. It's also clear that the most commonly used runway will be the shortest one as the prevailing winds are from the east. The telegram received on June 25 said nothing about the expansion being restricted to take offs only. But this also suggests to me that if she needed the whole length of that short runway then at close to take off speed wouldn't she possibly get her wheels into this extension of soft sand? Also let me ask the pilots out there a question. On a gravel runway what would be her stopping distance with her fuel remaining? Would she have been able to stop in the non extended 2250 Foot runway?
Based on my last few posts how can anyone say there "wasn't" a reason for to be anxious. Yes she probably didn't know most of what we know in hindsight but you guys are suggesting she had nothing to be anxious about. I'm suggesting she did. She really had no idea of the conditions of the airfield at Howland except what she got in the June 25 telegram. And we don't even know if it was provided to her. I'm confident she really wanted to get safely to California and declare her trip a success. This close to the end she wouldn't want to make a mistake.
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... the original arrival date was March 20, 1937, three and a half months earlier than the actual arrival date and the runways had to be completed by that earlier date.
I think that Earhart could be pretty confident that the airport would be waiting for her.
The idea I floated that she may have been anxious on the state of the airfield is based on these TIGHAR reported facts. Is it arguable that she may have been anxious about this brand new airfield? Yes. But how many of you pilots out there would take off for a mid ocean airfield just constructed at your request that no one had ever landed on and you know nothing about?? And it's near the end of your normal fuel load and no nearby airports as alternates? Is it LIKELY she was anxious? True or false?
I remember flying across the Atlantic in a single engine airplane looking for the mid ocean airfield on Santa Maria Island when the thought ran through my head, "Kid, you are taking it on faith that the guy that drew this chart wasn't just playing a practical joke and that the island is really where it is plotted on the chart." Then, just as quickly, I realized that the chart was drawn by grown-ups who took their responsibilities seriously, knowing that peoples' lives depended on the care they took in doing their work and "that was that," that first thought never crossed my mind again. And the island was there, just where it was supposed to be.
Earhart also knew that grown-ups were in charge of building the airport on Howland so I don't see any reason for her to have had any anxieties on that score.
gl
Yes Gary. I am sure grown ups were involved in all aspects of AE's flight. However she didn't make it so some grown up made a mistake somewhere.
Grown ups make mistakes. In terms of navigation look at this one. http://tighar.org/wiki/Howland_Island#Correct_location_of_Howland_Island_known_in_1937 (http://tighar.org/wiki/Howland_Island#Correct_location_of_Howland_Island_known_in_1937). One year before Amelia's flight Itasca discovered Howland Island was charted wrong. Now don't get me wrong here. I recognize that AE and FN had the correct charts. I raise this as an example of grown ups being well intended but still getting it wrong.
They didn't get the position "wrong" they got the position as accurately as the technology allowed, and certainly accurately enough for finding the island again by ships and Earhart, the Itasca didn't have any problem returning to the island. The position would have been "wrong" if an error had been made placing the island a hundred miles away from its actual position.
gl
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The point was simply that well intentioned people make mistakes. Call this an error if you like but the data is still wrong. Your point was we should trust grown ups will do the right thing by building a nice airfield that no one should doubt as to position. I simply point out that not everything done by people is accurate. I used an example. I am not apportioning blame.
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And one last point on this airfield on Howland. Look here http://tighar.org/Projects/Earhart/Archives/Documents/Reports/BlackCruise.pdf (http://tighar.org/Projects/Earhart/Archives/Documents/Reports/BlackCruise.pdf). Look under the heading "June 26 and June 27". Pretty clear that the report, written by Richard Black himself, indicates that the 300 foot extension was finished in time for AE to arrive. But it's a thin layer of gravel over soft sand and only to be used for Take off as its deemed unsafe for landing. It's also clear that the most commonly used runway will be the shortest one as the prevailing winds are from the east. The telegram received on June 25 said nothing about the expansion being restricted to take offs only. But this also suggests to me that if she needed the whole length of that short runway then at close to take off speed wouldn't she possibly get her wheels into this extension of soft sand? Also let me ask the pilots out there a question. On a gravel runway what would be her stopping distance with her fuel remaining? Would she have been able to stop in the non extended 2250 Foot runway?
Based on my last few posts how can anyone say there "wasn't" a reason for to be anxious. Yes she probably didn't know most of what we know in hindsight but you guys are suggesting she had nothing to be anxious about. I'm suggesting she did. She really had no idea of the conditions of the airfield at Howland except what she got in the June 25 telegram. And we don't even know if it was provided to her. I'm confident she really wanted to get safely to California and declare her trip a success. This close to the end she wouldn't want to make a mistake.
I think I answered your question before, see:
https://tighar.org/smf/index.php/topic,528.msg7061.html#msg7061
and:
https://tighar.org/smf/index.php/topic,528.msg7230.html#msg7230
From my prior post, the takeoff distance with no wind at Howland is 1,375 feet with 30° of flaps. For a no flap takeoff the distance would be 1,700 feet. A 20 mph headwind would shorten the 30° flap distances by 41.5% and a 10 mph headwind would shorten these distances by 22%. So with 30° of flaps and a 20 mph wind the distance would be 804 feet, with a 10 mph wind it would be 1070 feet. Without flaps, the reductions would be 38% and 20% so the distances would be 1050 and 1356 respectively.
BTW, I don't make this stuff up, see attached graph from Aerodynamics For Naval Aviators, the official Navy manual.
The calculation is easy. The takeoff speed of the plane with the lighter fuel load of 825 gallons for the shorter flight from Howland to Hawaii at the gross weight of 13,350 with no flaps is 93.5 mph and for a 30° of flaps takeoff the takeoff speed is 85 mph. The formula for computing the takeoff distance allowing for wind is:
Takeoff distance (wind) = Takeoff distance (no wind) (1 - wind speed/takeoff speed)^2
So for the 30° flap takeoff with a headwind component of 20 mph the calculation looks like this:
TD(w20) = 1375 (1- 20/85)^2
TD(w20) = 1375 (1 - 0.235)^2
TD(w20) = 1375 (0.585)
TD(w20) = 804 feet
You can work out the other examples yourself.
gl
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Btw If you look at Gary's takeoff calculations below you see that a runway of 2250, 2550 or even 2700 is cutting it mighty fine if she is using the east west runway. The one with the prevailing winds. If she had the same info as Gary then wouldn't AE be "anxious" about that airfield? The same woman who ground looped a fully loaded Electra in Hawaii on a runway with "known" conditions?
Taking off into a 15 mph wind at a gross weight of 13,350 requires only 932 feet with the flaps down and 1198 with the flaps up. Even it she could only get 550 hp per side without 100 octane fuel the distances only increase by 9% making them 1016 and 1306 feet so the east-west runway, even without any extension, is more than twice as long as it needs to be. And with a 15 mphwind out of the east there would be no reason they couldn't use the 4100 foot runway for takeoff. When flying a tail wheel aircraft you prefer not to have a crosswind that exceeds 20% of your takeoff speed but that is not a firm limit. Taking off without flaps, the takeoff speed is 93.5 mph so a crosswind of 19 mph or a bit more is O.K. and she certainly would not need flaps to takeoff from a 4100 foot runway. After all, what do you think you do if you have to takeoff and land at an airport that only has one runway, you just deal with the crosswind. If all of your flying has been at airports such as JFK, LAX or ORD (there are about 14,000 airports in the U.S.) then you are probably not aware that most airports only have one runway. The next most common runway arrangement is two runways that cross at close to a right angle with one long runway and one much shorter runway. Why not have two long runways, you ask? Because they cost a lot of money and you need a lot more land and you don't need two long runways. If the wind is such that the crosswind is not excessive then you use the long runway. If the crosswind is too strong for using the long runway then you have no trouble taking off on the short runway into the wind.
gl
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And one last point on this airfield on Howland. Look here http://tighar.org/Projects/Earhart/Archives/Documents/Reports/BlackCruise.pdf (http://tighar.org/Projects/Earhart/Archives/Documents/Reports/BlackCruise.pdf). Look under the heading "June 26 and June 27". Pretty clear that the report, written by Richard Black himself, indicates that the 300 foot extension was finished in time for AE to arrive. But it's a thin layer of gravel over soft sand and only to be used for Take off as its deemed unsafe for landing. It's also clear that the most commonly used runway will be the shortest one as the prevailing winds are from the east. The telegram received on June 25 said nothing about the expansion being restricted to take offs only. But this also suggests to me that if she needed the whole length of that short runway then at close to take off speed wouldn't she possibly get her wheels into this extension of soft sand? Also let me ask the pilots out there a question. On a gravel runway what would be her stopping distance with her fuel remaining? Would she have been able to stop in the non extended 2250 Foot runway?
Based on my last few posts how can anyone say there "wasn't" a reason for to be anxious. Yes she probably didn't know most of what we know in hindsight but you guys are suggesting she had nothing to be anxious about. I'm suggesting she did. She really had no idea of the conditions of the airfield at Howland except what she got in the June 25 telegram. And we don't even know if it was provided to her. I'm confident she really wanted to get safely to California and declare her trip a success. This close to the end she wouldn't want to make a mistake.
I think I answered your question before, see:
https://tighar.org/smf/index.php/topic,528.msg7061.html#msg7061
and:
https://tighar.org/smf/index.php/topic,528.msg7230.html#msg7230
From my prior post, the takeoff distance with no wind at Howland is 1,375 feet with 30° of flaps. For a no flap takeoff the distance would be 1,700 feet. A 20 mph headwind would shorten the 30° flap distances by 41.5% and a 10 mph headwind would shorten these distances by 22%. So with 30° of flaps and a 20 mph wind the distance would be 804 feet, with a 10 mph wind it would be 1070 feet. Without flaps, the reductions would be 38% and 20% so the distances would be 1050 and 1356 respectively.
BTW, I don't make this stuff up, see attached graph from Aerodynamics For Naval Aviators, the official Navy manual.
The calculation is easy. The takeoff speed of the plane with the lighter fuel load of 825 gallons for the shorter flight from Howland to Hawaii at the gross weight of 13,350 with no flaps is 93.5 mph and for a 30° of flaps takeoff the takeoff speed is 85 mph. The formula for computing the takeoff distance allowing for wind is:
Takeoff distance (wind) = Takeoff distance (no wind) (1 - wind speed/takeoff speed)^2
So for the 30° flap takeoff with a headwind component of 20 mph the calculation looks like this:
TD(w20) = 1375 (1- 20/85)^2
TD(w20) = 1375 (1 - 0.235)^2
TD(w20) = 1375 (0.585)
TD(w20) = 804 feet
You can work out the other examples yourself.
gl
Thanks Gary. I don't think I have ever accused you of making things up. If I have I apologize. I think you're extremely helpful and your threads are usually accompanied with supporting data.
To that end I have spent several hours researching your statement on how much gas AE was going to load on Howland for the leg to Hawaii. I presume there is some form of flight plan or logistics document that you are referencing. I have been unable to find it and would find it interesting to review. Can you point me to it? Thanks
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"...A total of 654 imperial gallons was filled into the tanks of the Lockheed after the test flight was completed. This would indicate that 1,100 US gallons was carried by the machine when it took off for Howland Island."
From the Chater report:
http://tighar.org/Projects/Earhart/Archives/Documents/Chater_Report.html
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Thanks John but its the fuel load thats expected to be loaded at Howland for trip to Hawaii. Not Lae to Howland. Gary did some takeoff distance calculations and indicated that AE was going with a lighter fuel load from Howland to Hawaii but I can't find the references to that. It flies in the face of what the pilots have said in this forum before about leaving for a flight with less than full tanks. But AE was her own woman.
I was thinking her takeoff distance from Howland was going to be the same as Lae with a full fuel load but Gary says she has opted for 825 gallons (presumed US gallons) from Howland. This makes her aircraft lighter and therefore requires a shorter take off distance.
I'm interested to see what he has as I looked for some type of planning document that would show how often she left with less than full tanks at different points in her trip. Ric had indicated that George Putnam arranged for fuel to be staged at all landing points in the trip. One of the reasons I'm guessing is availability and secondly for quality assurance. If you know where such a document is John then please let me know. Thanks.
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John
The operative part in the Chater Report states that All tanks were filled except for one 81 gallon tank that was about half full, i.e. lacked 40.5 gallons. Subtracting that amount from the total capacity of 1151 gallons gives about 1110.5 galons at takeoff. Every little bit counts.
The reason that the 81 gallon tank wasn't filled was that it contained 100 octane fuel which wasn't available at Lae. Pity.
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Thanks John but its the fuel load thats expected to be loaded at Howland for trip to Hawaii. Not Lae to Howland.
False. The Chater Report (http://tighar.org/Projects/Earhart/Archives/Documents/Chater_Report.html) is about the fuel taken on board for the Lae to Howland flight in 2 July 1937.
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No guys. Gary has suggested that AE was going to only load 825 gallons when she ARRIVED at Howland. We know she didn't so it's a moot point. I asked if Gary or anyone has information as to how much she was planning on taking off with from Howland.
Marty I know the Chater report is re the fuel taken on at Lae to Howland. What about Howland to Hawaii? I have searched Ameliapedia, this forum and the Internet in general. No luck. How does Gary know she only planned to load 825 gallons at Howland?
If I'm missing something then I sincerely apologize.
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Thanks John but its the fuel load thats expected to be loaded at Howland for trip to Hawaii. Not Lae to Howland. Gary did some takeoff distance calculations and indicated that AE was going with a lighter fuel load from Howland to Hawaii but I can't find the references to that. It flies in the face of what the pilots have said in this forum before about leaving for a flight with less than full tanks.
You have that slightly wrong. To be sure of the amount of fuel in any particular fuel tank a pilot needs that tank to be full since he can't trust the fuel gauge for that particular fuel tank. This doesn't mean that he always fills every fuel tank in the plane for every flight because it costs money to "tanker" excess fuel around the sky and the excess weight makes the plane go slower. The heavier the plane the more fuel it takes to go any particular distance so you do not want to carry fuel in excess of that needed for the flight leg plus required reserves, fuel to get to the point of first intended landing, thence to the alternate airport and then sufficient fuel for forty five minutes of flight at normal cruising fuel consumption. That is the requirement for domestic operations. For airlines operating internationally the fuel requirement for propeller driven airplanes is spelled out in Federal Aviation Regulations, 14 CFR § 121.641 (http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr&sid=b387a3f4bb55a11531c8b9993b3d6539&rgn=div8&view=text&node=14:3.0.1.1.5.21.3.28&idno=14)
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" Fuel supply: Nonturbine and turbo-propeller-powered airplanes: Flag operations.
(a) No person may dispatch or take off a nonturbine or turbo-propeller-powered airplane unless, considering the wind and other weather conditions expected, it has enough fuel—
(1) To fly to and land at the airport to which it is dispatched;
(2) Thereafter, to fly to and land at the most distant alternate airport specified in the dispatch release; and
(3) Thereafter, to fly for 30 minutes plus 15 percent of the total time required to fly at normal cruising fuel consumption to the airports specified in paragraphs (a) (1) and (2) of this section or to fly for 90 minutes at normal cruising fuel consumption, whichever is less.
(b) No person may dispatch a nonturbine or turbo-propeller-powered airplane to an airport for which an alternate is not specified under §121.621(a)(2) (http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr&sid=b387a3f4bb55a11531c8b9993b3d6539&rgn=div8&view=text&node=14:3.0.1.1.5.21.3.16&idno=14), unless it has enough fuel, considering wind and forecast weather conditions, to fly to that airport and thereafter to fly for three hours at normal cruising fuel consumption."
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Paragraph (b) is the one that applies to an airline flying to a location where there is no geographically available alternate airport, like flying to Howland Island. So today, a scheduled passenger carrying airline flying to Howland would only need to carry a three hour reserve of fuel.
In commercial operations you only put aboard the required fuel which then allows you to put on more payload. It is called "payload" for a reason, you charge by the pound, the more pounds of cargo, mail, or passengers you can put aboard the more money you make.
Even if flying a small plane you may not fill all the tanks in the plane if you do not need the extra fuel for the flight leg. For example, a Cherokee Six has two 25 gallons tanks and two 17 gallon wing tip tanks, total of 84 gallons. If 50 gallons is enough for your flight leg then you leave the tips empty (34 gallons, 204 pounds) so you can carry an extra passenger. But you fill the two inboard 25 gallon tanks so that you know that they are full when you take off.
Amelia did not always fill all her tanks, in fact she never did! The takeoff at Lae was with the most fuel she ever had in the plane and even then all the tanks were not full. On the leg from OAK to HON she only took 947 gallons. Hmmm... that's an odd number, why not an even number like 950 gallons. Let's see, the total capacity was 1151 gallons so 947 gallons is 204 gallons less than completely full tanks. The tanks behind the wing spars each held 102 gallons so Earhart filled completely all the fuselage tanks and the forward wing tanks and left the aft wing tanks empty. This 947 gallons was enough for the 2400 SM flight to Hawaii, only 156 SM shorter than the Lae to Howland leg, and Earhart said she had four hours of fuel left when she landed.
gl
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No guys. Gary has suggested that AE was going to only load 825 gallons when she ARRIVED at Howland. We know she didn't so it's a moot point. I asked if Gary or anyone has information as to how much she was planning on taking off with from Howland.
Marty I know the Chater report is re the fuel taken on at Lae to Howland. What about Howland to Hawaii? I have searched Ameliapedia, this forum and the Internet in general. No luck. How does Gary know she only planned to load 825 gallons at Howland?
If I'm missing something then I sincerely apologize.
Two ways. She took 1100 gallons for a 2556 statute mile flight against a 15 to 25 mph headwind so how much would be required for the much shorter 1900 SM leg to Hawaii against similar headwinds? 1900/2556 X 1100 = 817.86 gallons. The second way is that, according to Long, page 97, they put 825 gallons on board for the flight from Hawaii to Howland. Later they added another 75 gallons so that they would have the capability to return to Hawaii after flying for eight hours on course to Howland.
gl
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Gary, as always, a very comprehensive answer. Thank you. As a non pilot I don't even know the right questions to ask but I hope that other non pilots learn from my questions.
So determining the required fuel is really nothing more than following a formula that is used by all pilots.
Another question however. This is purely from curiosity. Why did the coast guard deliver 200 gallons of 100 octane to Howland. Not the "boost" question again, but why 200 gallons. Seems she had carried 100 octane in a much smaller tank on leaving Lae. I'm sure this is meaningless in the whole scheme but it just peaked my interest. Just the Coast Guard making sure they had enough in case of spills? I appreciate your time to answer this.
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Gary, as always, a very comprehensive answer. Thank you. As a non pilot I don't even know the right questions to ask but I hope that other non pilots learn from my questions.
So determining the required fuel is really nothing more than following a formula that is used by all pilots.
Another question however. This is purely from curiosity. Why did the coast guard deliver 200 gallons of 100 octane to Howland. Not the "boost" question again, but why 200 gallons. Seems she had carried 100 octane in a much smaller tank on leaving Lae. I'm sure this is meaningless in the whole scheme but it just peaked my interest. Just the Coast Guard making sure they had enough in case of spills? I appreciate your time to answer this.
Oh, it piqued your interest. ;)
No idea, four barrels of 100 octane and 12 barrels of 87 octane.
gl
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Thanks Gary. I appreciate the spelling lesson too. LOL!