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Highlights
From the Forum
March 26 through April 1, 2000
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March 26 through April 1, 2000 |
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Alan asked for any evidence that would steer him away from the TIGHAR theory. Maybe it's coming. Guy Zajonc, a Spokane attorney, who accompanied Timmer on the high tech sonar search at the 18,000 deep ocean area where the believed the Electra went down, says one of the targets "is the approximate size of the Earhart airplane". It was 60 miles offshore of Howland. Recently he showed imaging of that target on a local news broadcast. It looked (I guess) like the "trails" by the "7" site on Niku, a long drag mark on the white ocean floor with an "object" at the end that, he says, is not a geological piece. It could have been anything. But Timmer, who now lives in Austria, says they will return as soon as possible to photograph it. Unless the Longs and their group get there first. Stay close to your tv. This is an interesting race, eh what. (quote from Maude) LTM, From Ric Fred Goerner went diving in the harbor at Saipan and brought up a generator that he thought might be from Earhart's plane. Buddy Brennan went digging in the ground on Saipan and brought up a scrap of cloth he said was Earhart's execution blindfold. Joe Gervais went to a reception in East Hampton, Long Island and found Amelia Earhart (although she claimed her name was Irene Bolam). Randall Brink found a wartime photo of a twin-tailed airplane on a Japanese airfield and thought it might be Amelia's. TIGHAR has found a number of artifacts on Nikmaroro that we feel may be associated with Earhart and the airplane. Timmer and company have a sonar image of what they say is an Electra-sized object on the ocean floor. Who is right? Is anyone right? How do you tell? What team do you root for? Or do you play it safe and remain neutral? Call it a race if you want to. TIGHAR is not in a race. TIGHAR is just following the evidence and looking for more. LTM, |
Please explain how a time aloft estimate can be independent of head or tail-winds? (I'm not being flip, here; I really wish to understand the process better.) I understand the fuel management schedule, but does not such a schedule take into consideration an assumption of average head/tail-winds? The Cal-Tech analysis allocates a much lesser average head-wind speed than do the Longs -- I believe it was in the 13-16 knot range as Mr. Jacobson suggests. The Cal-Tech conclusion is a likely 20:38 and a maximum 23:38 assuming no headwinds. Note, also, that Long's assumption relies on headwinds radio-reported from the Itasca (but apparently not received by Earhart) in addition to Earhart's own radio report. David Evans Katz From Ric I'll take a stab at this and welcome corrections or elaboration from thems with hours and better aeronautical educations than mine. Once the airplane is aloft it neither knows nor cares what the headwinds, tailwinds, or crosswinds are and hours aloft (endurance) will remain unchanged no matter how many miles are or are not covered. There is, however, a technique used primarily in transport aircraft where the recommended power settings are increased when faced with significant headwinds. Long alleges that this is what Earhart did, but the only evidence he cites is a fanciful interpretation of her phrase "SPEED 140 KNOTS" quoted in the Chater report. He says that she was referring to her indicated airspeed, thus proving that she had increased her power to attain an indicated airspeed 10 knots faster than the airplane's recommended best economical cruise of 130 knots. What he does not explain is why on earth any pilot would include indicated airspeed, rather than groundspeed, in a position report, and if she did, why she would convert the mph she read off of her airspeed indicator to knots before making the report? The phrase "SPEED 140 KNOTS" in a position report is almost certainly a groundspeed report provided by the navigator (who works in knots). In this case it would indicate a tailwind component of 10 knots for that particular segment of the flight. If Long wants to allege that it means something different than that he has to show some reason other than that it fits his own preconceived notions of what happened. The other problem with Long's allegation that Earhart (suicidally) departed from Johnson's recommended power settings is that Johnson specifically addressed what to do in the event that stronger than expected headwinds were encountered. He didn't say to bump up the power. He said to lean the mixture. I haven't seen the Cal-Tech analysis. What is the Cal-Tech analysis? Have you seen the Cal-Tech analysis? Who did the Cal-Tech anaylsis? Who paid for the Cal-Tech analysis? What assumptions did it start with? LTM, |
> From David Evans
Katz A basis for the Longs' conclusion about the Electra's fuel consumption that day is the statement, "it is a mathematical certainty that an 8.5 percent increase in ground speed will result in an 8.5 percent increase in hourly fuel consumption." As several of us have noted here in the past, the correlation is certainly not one-to-one, and the Longs' basic mathematical assumption is incorrect. First, the Longs' correlations to fuel consumption should be related to true air speed, not ground speed (ground speed is, in practical terms for making fuel consumption estimates, almost meaningless, and ideally, the only way to really calculate fuel consumption accurately is to measure fuel flow over time). The fluid dynamics involved with the airframe (that is, air resistance increasing at a rate far greater than 1:1 with airspeed) and the effect on engine performance of different airflows into the manifold make precise fuel consumption calculations so fraught with variables that I'd be uncomfortable extrapolating too much precision over long distances without actual fuel consumption tables produced from real-world testing with the airframe and engines involved. Add to this the unknown wind conditions and cruising altitudes for the majority of the flight and we have lots of uncertainty. In any event, the flawed understanding and "math" quoted above utterly ruins the authors' credibility concerning any conclusion they may have drawn about the Electra having run short of fuel. The "ran out of fuel near Howland" scenario requires speculation, including speculation that headwinds were unusually high and uniform throughout the flight (very unlikely), and speculation that fuel evaporated on the ground at Lai (there is zero proof of this). On the other hand, as has been repeatedly demonstrated here, the Electra appears to have had sufficient fuel to have continued flying for several hours after reaching Howland, which they couldn't find, probably because of dappled cloud shadows (one has to have flown over the vast Pacific to fully appreciate how important this problem can become), a non-functioning DF, and the added confusion of a 6 or 7 mile displacement of the island on their chart. Noonan's competence as a navigator is now generally unquestioned in reasoned discussions, his prior experience and great skill have re-emerged through documentation from the era (TIGHAR has played a significant part in this), and in essence, this tends to enhance the probability that they flew the LOP to Gardner when Howland failed to appear. william 2243 |
I think David Evans Katz is confusing or mixing endurance with range in his posting. The fact that AE sent the, "We must be on you but can't see you" message indicates she reached the area of Howland close to the anticipated flight time schedule. No pilot, with reasonable knowledge of aircraft performance, would simply sacrifice range and endurance by increasing airspeed to get to Howland at a set time. Achieving normal fuel consumption would be a far greater priority than getting to Howland at a set time. It is much more logical to assume that the winds (which are seldom constant over such a long flight) did not average 26 kts of headwind and that AE did fly the airplane to get the proper range an endurance as described by Johnson's tables. For this reason alone the 24 hour endurance is a far more logical assumption than the 20 hours and 30 minutes suggested by Long and David Katz. Dick Pingrey 908C From Ric Again, for those who may not know, Dick is a retired airline captain with extensive experience in all flavors of flying machines from antiques to balloons. |
For what it's worth, having just waded through the Longs' book and tried to use it, what I find maddening about it is their cheerful mixing of documented data, first-hand (though often long after the fact) anecdote, deduction, speculation, and plain invention into something that they present as though it were fact, coupled with a citation system that makes it virtually impossible to sort out what the real source of their information is -- let alone to judge its reliability. However logical some of their assumptions may be, they've presented them in such an unprofessional way that it borders on irresponsibility. Tom King From Ric In all fairness we should acknowledge that much of what makes the book so annoying was dictated by the publisher, but the Longs' have to accept responsibility for their basic premise and methodology. I suspect that if we could see the stuff that was cut out to make the book more "readable" it would only reinforce the conclusion that the Longs' calculations that so impress an uncritical public are, in fact, merely an exercise in backing into the numbers. I certainly don't think there was ever any intention to mislead anyone. I think that they honestly don't realize what they've done. |
Indeed there are some rather interesting questions arising over this matter of Gallagher's radios... let me see if some can be clarified. Assuming there was AC power available from a generator on Niku in 1940, it more than likely would have been 220 volts, not 110/115. The British "mains" are 220 volt, as they are in much of Europe. The RCA Radiola-80, if it was not an export model, would have required 110/115 volts. A large and heavy stepdown transformer would be necessary to use it on a 220 volt supply. THEREFORE, it is quite likely indeed that the radios were operated from batteries. The typical radio of the era required either 2.5 volts or 6 volts for tube heaters ("valves" to the British) at several amps, like 2 to 4... this would be supplied, usually, from a wet-cell storage battery. The sets also required "B" batteries of from 45 to 135 volts, at anywhere from 20 to 100 milliamperes depending upon how many tubes were involved. These B batteries were big dry cell types. They were not rechargeable, were expensive, and did not last long (depending upon how much listening you did). The "vibrator" (no porno connotations!) power supply in the inventory was a means of eliminating the B batteries. The vibrator supply operated from the storage battery. It used a mechanical device (vibrator) to convert DC to AC, then stepped up the voltage, reconverted (rectified) it back to DC at a higher voltage to operate the radio. OK... there had to be some means of recharging that storage battery. Gasoline-powered generator? "Native-powered" (bicycle type)? Somehow that last one fits well with my conception (stereotypical?) of the "Englishman in the tropics." As for ham transmitters of the time, Gallagher (if he was indeed a ham) could presumably have had a low-power rig, more than likely home-brewed as were most (probably 95%) ham transmitters of the age. Agreed, he would have had a separate transmitter and receiver. It's kind of interesting to see how modern observers equate their own experience (transceivers, CB radios etc) to what they think was feasible. A one-tube oscillator can work the world, if the "wind is right" and as for antennas, a wire strung between two big trees works just great. In 1937, Gallagher on Gardner Island would have been a popular contact. Even today, it's considered "good DX." Hey, seriously.... maybe TIGHAR should consider mounting a "DXPedition" to Nikumaroro to coincide with Niku IIII... it'd be great publicity. Any number of groups do this; large ham clubs (with money) being one possibility. It's a way to help pay for the ship. In the ham radio world there is a group called "Islands On the Air" and many hams collect certificates or QSL cards from rare islands, trying to "work 'em all." Niku has GOTTA be RARE DX. Trust me on this. And the QSL card could be a true collectors' item... a shot of the Electra superimposed over one of Niku, with AE and FN in a background of clouds... I'll design it! (Since I can't go, that'll be my contribution.) By the way if Gallagher was a ham, he'd have probably been first licensed in England, with a call beginning in "G" (example: G3XXX) and in the Islands would have probably been issued a "V" call (more than likely a VR, ex. VR4XX). The records of the WPHC might even show this, as the license could have come down through those channels. We could even try this DXPedition idea to Kanton... if the radio club could help us charter a Herk, maybe we could get the backhoe or Bobcat we need to find the engine. 73 Mike E. the Radio Historian From Ric There have been several HAM expeditions to Kanton. There's a group that charters a Lear out of Hawaii. To get heavy equipment to Kanton would require chartering a civilian Herk (about $200,000. We checked.) That would take a pretty wealthy HAM club. I know of at least one HAM expedition to Howland using a small ship out of Hawaii called the Machias. It was a disaster. The problem for
us in taking people along who are not part of our expedition is that it
cuts down on the number of bodies we have to do our work. Nai'a
has shown herself to be the best ship for our purposes and she can only
accommodate a maximum of 18 passengers (and 14 is a lot more comfortable).
A 21 day trip runs about $120,000 as long as we keep it low-tech. If we
have a camera crew along (usual price for exclusive rights, $50,000) that
cuts us down to 12. If we took on, say, four well-heeled HAMs for $20,000
each that would go a long way toward completeing the budget but then we'd
be down to an 8 person TIGHAR team AND we'd have Nai'a trying to
serve the often conflicting needs of two separate groups. There is ample
evidence to support the hypothesis that I am a glutton for punishment,
but I'm not sure my appetite is THAT big. That said, I can see a possibility for one member of the TIGHAR team being a HAM who would work the world from Niku in return for contributions. I'm not sure exactly how that would work but then I don't know much about the wonderful world of HAM radio. Similarly, we've played with the idea of daily expedition internet updates via satellite but haven't yet found a way to make it work economically. Ideas welcome. LTM, |
Ric says: "Not to put too fine a point on it, Harry thinks we're nuts." I don't think that's quite true, or fair. Harry says that since "so many people" say she was captured by the Japanese, that must be what happened, but basically, it's just not something he's deeply interested in. He IS, or was the last I heard, glad that we've been looking into Niku, and the PISS, and he retains a great affection for Gallagher, Koata, and a lot of the other dramatis personae in our drama. He and Honor are both now in the mid-late 90s, live in a retirement home, and Harry is completely blind. I now communicate with them through their son, who lives in Adelaide. I haven't been bothering Harry with questions lately, but just sent him a piece I wrote on Gallagher and his demise, which his son says he'll read to them both the next time he visits. Thanks to Harry, we early on got stuff from the Barr Smith Library, but it was basically what Harry thought would be of interest; there might well be more there. Thing is, it's likely to be bits and pieces here and there, and material that would be interesting contextual stuff but not likely to contain any smoking guns. It would be great to have someone physically go through the material; I'm sure there'd be interesting stuff. Just hard to ferret out. LTM (who'd love
to spend a year or so in the B.S. Library) From Ric I certainly didn't intend any disrespect for Harry Maude. He is, without doubt, a giant in his field but, as Tom points out, Amelia Earhart is most definitely not his field. I suppose it's pure
coincidence that his notes on PISS ended up in the BS Library. |
Thanks a lot Randy for your statement that strengthen the hypothesis that there was at least between 3 and 4 hours of fuel left after 19.2 hours of flight. Following K. Johnson telegrams I was not able to go under 24 hours of duration. As you said, Wind has no effect on duration time. We know for sure that the last reported radio message occured after the 19.2 hours of flight. The strength of the signal suggested that the electra was within 100 miles from Howland, so a distance covered so far of 2456 statute miles seems to be reasonable. The average speed, with these numbers, would have been 115 knots ( 211 km/h ) real speed( 128 mph ). The expected indicated speed was 140-150 kt. So, the constant head wind would have been roughly 25 knots.There was theoricaly 4.8 hours of fuel left... enough to cover 547 nautical miles at this speed, enough to reach Niku... Of course, I am not a specialist as you are, but even from my "rookie" point of view Long's affirmation that the Electra went dry after 20 hours is doubtful. LTM From Ric The Electra's recommended long range cruise speed was 130 knots or 150 mph. |
>Johnson's 24 hour
aloft time is independent of head or tail winds, Ric - If you were In AE's position, wouldn't you consider deviating from Johnson's power management schedule in the interest of fuel conservation? What measures might have been open to AE in terms of leaning, power / rpm settings that she might have considered to extend her range. Seems to me that short of turning Fred into jetsam, she would have considered some extreme leaning measures. Is there a way we might calculate the changes such measures might have had? LTM (who thinks that perhaps her lack of radio transmissions resulted from tossing the radio gear overboard - NOT!) Andrew McKenna 1045C From Ric You can make a pretty good argument that she might well have deviated from Johnson's figures because:
On the other hand, it's clear that Johnson never had a chance to fly new tests on the airplane after it came out of repairs. AE left the very next day. The numbers he had given her for the Oakland/Honolulu flight were the best she had and they had worked great on that flight. Contrary to any suggestion that Johnson's numbers were designed for ideal conditions, Johnson knew he was setting up a plan of power management for Amelia Earhart. He had flown with her and was certainly aware of her limitations and his set of recommendations is greatly simplified over what would be needed to extract the optimum from the airplane. It doesn't seem too likely that Amelia would get all creative. |
I have been studying, slowly, the most recent TIGHAR Tracks, Vol 15 and wish to offer a point in support for the AUkeraime Site. Gallagher's Clue #2 states: "Bones were found on South East corner of island. . . ". Tighar has appeared to assume, in the modern context, that this refers to the actual south east point of the island. In her interview, Emily Sikuli responds to a question from Tom King: TK: Any other parts of the island where people went regularly? ES: Only where they intended to clear and plant coconut trees. The trees had been cleared to the SE end. First, I have emphasised certain parts of each of the quotes. I am aware of the parenthetical note behind Ms. Sikuki's response that she gestured over the map past Aukauraime, however none of that area is ever cleared. To Gallagher and Sikuli, the southeast end/corner could well mean the southeast limits of the planting. If according to Sikuli, people were only going to the southeast limits of the planting area, then they never would have been to the south east point to find the bones, much less around the point to the 1996 site. It would make sense that the people charged with locating and clearing the proposed coconut sites would search and "survey" those areas. They had no need or desire to probe further southeast to the point or around the point. Second, Gallagher is neither a naval person or aviator, and appears to have come from a rural background. I have found nothing that says he was a farmer, but his appointment to oversee this work implies, at least to me, that he might have had some background in this field, although I acknowledge administrators are not always, if ever, well versed in their assignment. In any event, people who are not naval or aviation oriented, do not, in my experience utilize nautical miles, they use statute miles. Clue #10 refers to "two miles" from a "small grove" of cocconut trees". Your map uses nautical miles which extends the reference nearly 1/3 of a statute mile. (1.15 to 1) The only existing groves, per your map, were on either side of Tatiman Passage and almost exactly two statute mile from the Aukeraime site. Additionally, most of the area between Tatiman Passage and Aukeraime would have been uncleared when the bones were found; your map and records indicating they were cleared and planted by June of 1941. Opposing this theory, the only likely clearing areas in 1940 appear to be northwest of Kanawa Point. Unless the survey/clearing crews were way ahead of the planting crews, they would not have reached Aukeraime by October of 1940, especially if it was through two miles of "impenetrable (sic) belt of brush". They would have had to clear as they go. This brings me to the question of when the site marked on your map as "cleared and planted" but undated, immediately north of Kanawa Point and across the lagoon, was cleared and planted. This appears to be within the two mile arc clockwise from Tatiman Passage. It does not appear to have been searched by Tighar crews, is opposite Tatiman Passage and lies within the direction of flow arcs through the passage. If I were Earhart and Noonan would I search counter-clockwise and attempt to cross Tatiman and Bauareke Passages or would I search clockwise around the northwest point of the Island, thence along the northeast shore? If help were coming, wouldn't it come from the northeast and wouldn't I keep to that side to watch for it? From Ric The area across the lagoon from Kanawa Point is shown as cleared and planted on a map prepared by Lands Commissioner P. B. Laxton in 1949. It was probably done at the same time that Nutiran was developed (1949). Incidentally, Laxton's map shows the entire shoreline from the north point above Norwich City down to the Loran station at the southeast tip as "bush reserve." Apparently, as far as Laxton knew, whatever was done at the "7" site was not "clearing and planting." He describes it only as the site of a "house built for Gallagher." That has never made a lot of sense to us. Irish was nothing if not a workaholic. It's hard to imagine him having any use for a vacation cottage. Some of the assumptions you make above are a bit shaky. > If according to
Sikuli, people were only going to the southeast limits of Tom asked where people went "regularly." Certainly, all parts of the lagoon shoreline were readily accessible by canoe and any number of reasons could take people to anywhere along that shore --- bird hunting, turtle hunting, or harvesting kanawa trees. The latter is my favorite as the reason that originally took workers to the place where the bones were found. Remember, as best we can figure, the skull was found sometime around April of 1940. That's too early for any clearing operations down at Aukeraime which seem to have begun only after Gallagher's arrival in September. In December 1940 Gallagher says that the kanawa tree from which the bone box is made was standing on the lagoon shore near the discovery site "until a year ago." That places the time when the tree was cut down (and, by definition, when people were at the site) very roughly around the time when the skull was found ---- call it sometime in the first four months of 1940. >Gallagher is neither
a naval person or aviator, and appears to have come Gallagher was a licensed pilot and he owned his own nautical sextant and almanac. He had worked for a year on a farm in Ireland but he also had a degree from Cambridge and a year of medical school. This was a highly educated young man. Worrying about whether his reference to miles was statute or nautical is, I think, trying to read far too much precision into a casual comment. For one thing, how on earth could he measure long distances accurately on the island? And why would he need to? No good map of the place was yet available. It seems most likely that his "less than two miles" is a rough eyeball estimate. >If help were coming,
wouldn't it come from the northeast and wouldn't I Depends on where the help is coming from. If it's Itasca coming to the rescue within the first few days, she'll be coming down from Howland --- from the northwest. Right there by the Norwich City is a good place to be. Later on, if you're hoping to spot a ship that just happens to be going by you're probably better off somewhere along the northeast-facing shore where you can watch for traffic moving between Samoa and Hawaii. In any event, anyone camped near the Aukeraime site can't see the ocean at all. The more I think about it, the more I like the "7" site (aka "1996 site", aka "house site"). LTM, |
The "less than 20 gph" figure on the Hawaii leg is pretty clearly per engine. I don't have Last Flight handy, but my recollection is that AE's handwritten notes on this entry are reproduced in the book and say that the Electra was at 10,000 feet and indicating 120, which would mean a TAS of about 144. This is consistent with the 38gph Johnson figures for reduced weight at 150. What I find interesting is that AE considered this to be throttled back (rather than SOP), and her casual attitude toward exact fuel flow --- which may tell us something about her management on other legs. From Ric I do have Last Flight handy and your recollection is correct that her notes are reproduced in the book. Here's what she wrote: "Daylight comes at last. The stars fade. We are throttled down to 120 indicated airspeed so not to arrive in darkness. We are burning less than 20 gals. of gas at 10,000 ft...." How is that "pretty clearly per engine"? That's not what she says. |
I hope Ric DIDN'T make the remark that TIGHAR's findings by the scientific method would have been considered conclusive (if the matter concerned anyone else but AE). Although I admit my personal opinion is that they went down in the ocean, I am willing to keep on open mind IF the rules of the scientific method are strictly adhered to. Going down the list of "conclusive proof?" 1. Shoe fragment(s)
relates to AE or FN? --- Not proven So please help me keep the faith in the "scientific method" ( no sarcasm intended here) and tell me that you all (especially Ric) are not prepared to say that you now have CONCLUSIVE proof that AE and FN went down on Niku. Regards, From Ric I did say it and
I meant it, but don't worry, we accepted a long time ago that the standard
of proof required for acceptance by the general public that the Earhart
mystery is solved is far higher than the "preponderance of evidence" standard
that prevails in a civil courtroom. The general public, and even many
people who have a particular interest in the Earhart case, have neither
the patience nor the inclination to really familiarize themselves with
a complex body of evidence (your listing above is a good example). They
require something simple so it's up to those of us who are willing to
deal with the complex to follow that trail until it leads to something
simple. Fortunately, it is the nature of any investigation that if your
basic hypothesis is true, the more data you collect the more obvious their
validity becomes. When we started this project, all we had was some navigational
logic that made Gardner seem like the most likely place. Now, twelve years
later, we're trying to identify the castaway(s) who died on Gardner and
trying to confirm anecdotal accounts of a pre-war aircraft wreck on the
reef. Eventually we'll find something simple enough for everyone to understand. LTM, |
It is important to understand several factors with regard to Amelia's fuel management. Hopefully, some of the following comments may add perspective. 1. The rate of fuel consumption is fundamentally a function of engine speed (rpm) and the fuel / air mixture ratio. For maximum range (distance) or endurance (time), it is desirable to keep mixture ratio on the lean side and reduce the engine speed consistent with producing the necessary power to maintain flight equilibrium. 2. There is another factor that comes into play involving the propeller. The engine develops brake horsepower and delivers it to the propeller shaft. The propeller converts this power into thrust (sometimes referred to as thrust horsepower). The conversion is always less than 100 percent due to losses. Propeller efficiency varies with several factors including aircraft speed. It diminishes with a reduction in speed. A nominal propeller efficiency in that era would be around 80 --- 85 percent, less at lower speeds. (Propeller characteristic charts are used to determine what the efficiency will be.) 3. As a consequence of items 1 and 2 above, Kelly Johnson ran flight tests to determine cruise conditions (engine power settings consisting of mixture ratio, rpm and manifold pressure) that would give better fuel consumption rates than power settings normally recommended by the manufacturer. These data were related to standard atmosphere conditions. 4. The recommendations put forth by Kelly Johnson were generic to long distance flight during Amelia's planned world trip. The fuel management plan was applicable to any long distance flight such as Oakland - Hawaii, Lae - Howland, Howland - Hawaii or whatever. The Oakland - Hawaii flight offered Johnson an opportunity to verify his plan or adjust it as needed. 5. His recommended engine operating conditions deviated from standard power settings recommended by the factory. For this reason, he forwarded his test results and resulting recommendations to Pratt & Whitney for concurrence (which was forthcoming). 6. Amelia did not have much latitude with regard to deviating from Johnson's recommendations. Further leaning of the mixture ratio ran a strong risk of elevating cylinder temperatures beyond what was prudent. Cylinder temperature was one of the parameters Kelly monitored during his tests because he was concerned they would rise to catastrophic levels. 7. Kelly gave her a final power setting to be used if needed in the event her fuel was running precariously low (unexpected headwinds) during the Oakland - Hawaii flight. This was to be used toward the end of the flight when the aircraft was much lighter due to fuel burnoff. 8. In steady-state equilibrium flight (in this case cruise), thrust produced by the engine/propeller combination exactly equals drag. Similarly, the amount of lift generated by the wing equals aircraft weight. Any modifications made to the Electra while undergoing repairs (a change in antenna arrangement, for instance) would have a very minor and probably imperceptible impact on airframe drag. The basic aerodynamic characteristics of the airframe remained unchanged. Kelly Johnson did not need to run additional flight tests prior to the second world flight attempt. The previous results were still valid. I am confident in this base on a technical assessment, and the fact that Lockheed would have been in jeopardy had aircraft aerodynamic characteristics appreciably changed. 9. In conclusion, there is no reason to believe that Amelia Earhart did not follow the basic precepts of Kelly Johnson's fuel management plan. In fact, every logical reason to believe that she did. 10. What Johnson's fuel management plan did not address, as I have indicated in previous Forum postings, include fuel consumption rates during takeoff and climb; excursions to altitudes other than that recommended; various factors inducing fuel losses; and atmospheric conditions differing from a standard atmosphere. From Ric Thank you Birch. |
While I am inclined to agree with the basic thrust of William Webster-Garman's comments concerning the Long's book and their "flawed understanding and math," I respectfully suggest that determining probable fuel consumption for the Electra is not quite as daunting a task as he portrays. A reasonable engineering analysis can at the very least bound the situation with respect to fuel remaining following Amelia's final radio transmission. If nothing else, this tends to eliminating some of the wilder assertions about what happened to her. "Real-world testing" to determine a fuel consumption rate for several power settings was performed by Kelly Johnson, and thus forms part of the basis for estimating probable Electra endurance after departure from Lae. Only if one assumes that Amelia deliberately departed (routinely and significantly) from the Johnson fuel management plan can the exercise be futile. I cannot conceive of a logical reason for Amelia to have made such a departure. Engine fuel consumption is independent of ground or air speed. Further, airframe thrust and drag do not enter into fuel consumption equations. The engine consumes fuel at some given rate whether powering an airplane in flight or running in a static test on the ground. |
I have a question that Forum members may be able to answer. If it has been asked and answered previously, my apologies. The current TIGHAR hypothesis is that Amelia Earhart descended on or very near Gardner Island after turning south from her nominal course toward Howland. As she failed to see Howland Island, why is it more probable that she was then able to find Gardner? Was it because the location she had for Howland was erroneous and the coordinates for Gardner were correct thus enabling Noonan to find the island? From Ric I'd put it this way: Flying direct to any island using only DR and celestial, whether it's Howland or Gardner, is very difficult. It's even harder if the island is tiny, does a pretty decent impersonation of a cloud shadow, and is not quite where you thought it was. By contrast, finding one of several islands that are distributed along a line by simply flying down that line is easy. It's even easier if one of the islands is relatively big and has tall trees and a turquoise lagoon. |
I think a lot of the arguments that have been put forth in the last couple of days in favor of Aukaraime over Seven as the bones discovery site are serious food for thought -- and I want to think about them some more. I think we need to be careful not to put all our eggs in the Seven basket. The scary things about Aukaraime as the site are, first, that we don't have any real idea how big a site we're talking about. Sure, the place from which the shoe parts found in 1991 came is pretty small, but there's no guarantee that this is the part of the site where the bones were, assuming the bones were ever there. In fact, there's good reason to assume that the bones were on some other part of the site, if they were ever there, since Gallagher obviously missed the shoe parts that TIGHAR found (unless somebody brought them back from Fiji, and I agree, that's far-fetched). But Aukaraime South is a big place -- a lot of area to search. We walked over it in '89, but not in anything like the detail that would be needed. The other worrisome thing is that as I understand the way things worked at the Loran Station, and to judge from terrain modifications we saw in '89, the road to the village from the Station went right through Aukaraime South near the ocean shore, raising the potential for a lot of ground disturbance. This is no reason to say that Aukaraime South can't be the bones discovery site, of course, but it is to say that searching it is going to be a much more daunting endeavor than searching the Seven Site. One question that arose yesterday or the day before was about the hole in the ground at the Seven Site, wondering why it was so large if it represented digging for a skull. Good point, I thought, but it might be accounted for by the likelihood that the guy who did the burying -- Koata (assuming he's the one who did it) wasn't there, so they weren't quite sure where the head was, and hence wound up digging a larger hole than if they had it pinpointed. On the other hand, a large shallow hole might result if people were using dynamite to dig a well, as we know the colonists did. Which raises a question: how hard is the ground at the Seven Site? LTM (who recommends
against excavating with dynamite) From Ric The ground at the "7" site is essentially coral rubble with some humus mixed in. Less humus and more rubble than at the Aukeraime site. The digging would not be easy going. In my estimation the hole was dug with a shovel. It's not nearly big enough to be caused by blasting. |
Ric wrote: > When we started
this project, all we had was some navigational To me this statements of Ric's is my "smoking gun" and is why I have continued to follow TIGHAR'S progress and continue to give support to their efforts. I still believe (as Ric has said) that many people will never look at the evidence collected by TIGHAR objectively. I still believe (and this was really my original point) that unless irrefutable proof is found ie. a dna match or an engine with a serial # that history will never give TIGHAR their due( and even if proof is found many won't believe). There will always be doubt in many minds about the fate of Amelia and Fred. Will "history" evaluate TIGHAR's "scientific approach" and say yes they really followed the scientific method if there isn't a "smoking gun". Now Ric's reply to my original post on this was very good-- to those who want to get off their duffs and do something about this mystery-- fine-- for them they have their own satisfaction. To the rest of the world I still say they really won't take the time and look at all the evidence collected and won't really care unless they read in the press that the "mystery" has been solved. |
Birch Matthews wrote, > While I am inclined
to agree with the basic thrust of William I was referring only to the high level of precision claimed by the Longs, who write that they have calculated exactly when the Electra ran out of fuel. 1) Their math is wrong. 2) They ignore important variables which have unknown values and which would be essential for any reasonable calculation approaching even a half hour of the accuracy they claim. 3) Their conclusions are based on assumptions that involve speculation. For example, they invent a fuel evaporation scenario and other speculations for the purpose of depriving the Electra of enough fuel to match their flawed math and run out of fuel near Howland. Dick Pingrey recently made the excellent point that the 24 hour endurance of the Electra is the most direct indication that they could have reached Gardner from the vicinity of Howland. From that perspective, losing 4 hours of endurance would have required that the flight experience a level of difficulty for which there is no meaningful evidence. If NR 16020 did ditch near Howland, the Longs haven't proven it. william 2243 |
Ric said: " . . . we accepted a long time ago that the standard of proof required for acceptance by the general public that the Earhart mystery is solved is far higher than the "preponderance of evidence" standard that prevails in a civil courtroom." The preponderance of evidence is a tricky beast. What works in a courtroom does do squat in the lab, or elsewhere. What follows is a simple exercise (as best I remember) from a course taken back in intelligence school years ago. The names have been changed but we all know who we're talking about. :-) The following 10 facts are all 100 percent true and were collected from sifting through thousands of pages of classified and unclassified material.
What type of report would you write using this data? Out of about 25-30 students, only a couple came up with the correct answer. If you answer this correctly a recruiter from (fill in your favorite government intelligence agency, CIA, ATF, FBI etc.) will call. :-) LTM, who had the
wrong answer. From Ric Okay, I'll play. I'll write my "report" but won't post it until others have had a chance to submit their offerings. |
>...finding one
of several islands that are distributed along a line The Sun Line across Howland coincided with the Sun Line through Gardner. --For a while. As the morning wore on, the azimuth of the Sun changed, the LOP alignments changed, and the two LOPs were farther apart. Parallel, but separate. At some time once it was certain that Howland was left behind, only the Sun Line through Gardner would be useful. At first, it wouldn't take much of a dogleg to get over onto it. Then tracking along it could begin. Just what is being referred to in my discussions of Sun Line tracking might often have been unlear. For example, there is a Sun Line across a point at one instant, say 18:00:00 GMT. An hour later, the alignment of the Sun Line across the point would be different. Has the Sun Line moved, or are we dealing with different Sun Lines? Really, although it appears to have moved, a given Sun Line exists only for an instant. From instant to instant, from second to second, new Sun Lines are observed. So when a pilot tracks along "a" Sun Line, he is, by taking Sun observations from time to time, really using a new Sun Line each time. Over the course of several hours, the change in the course might well be apparent. --Leaving the Howland area on a True course of 157 and eventually tracking across Gardner on something noticeably less than that. --The effect is that the plane would home in on Gardner, flying along a slight curve, rather than fly an exactly straight line to it. I'll calculate what the course would be for hourly intervals after 1800 GMT; also, I'll check on just how far apart the Howland and Gardner LOPs would be at those hourly intervals. This would be clearer with an illustration. Is there a TIGHAR mailing address I can mail chart drawings to, for you to see them? Sincerely, From Ric By all means. |
> Here's what she
wrote: It's pretty clearly per engine because a 4 or 6% reduction in airspeed (from 150 or 155) to 144 (rough TAS for 120 indicated at 10,000) will not cause a 45 to 50% reduction in fuel flow in any airplane under any set of cruise conditions. Just think about it. If you could fly at 144 on half the fuel required to fly 155, range would increase 85%! (Twice 144 = 288; 288/155 = 1.858.)(And, of course, endurance would double.) Reductions in airspeed do produce slightly greater percentage reductions in fuel flow(for example at some point along the speed range, a 5% reduction produces a 6% reduction in fuel consumption). This is why speed reduction produces "greater efficiency", until the magic speed called "V L/D" is reached. "V L/D is the indicated airspeed at which an airplane goes the most miles on a gallon of fuel. It is not to be confused with V E, the maximum endurance speed ..." Peter Garrison, "Long Distance Flying", page 137. Below V L/D there's no further increase (and may be a decrease) in efficiency. Even if AE meant 120 True Air Speed, consumption could not have been much less than (say) 30 gph. I think she meant what she said (120 indicated) and read the (dual needle?) fuel flow meter exactly (but improperly) - the (two) needle(s) were slightly below 20, for a total fuel consumption of under 40. Just what one would expect. From Ric How say ye, gentlemen? |
Alan Caldwell wrote: >...IF the author
has thought it out well first and has some support Although I subscribe to all the logical arguments put forth to justify a SE heading on FN's LOP to the Phoenix Island Chain, I would submit that there is/was also a reasonable basis for also considering a turn-back to the Gilberts, AE/FN knew that the Gilberts were ... inhabited ... We've had much speculation about FN's plan 'B' for an alternate landfall in the Phoenix Islands (his LOP for Howland, on it's SE leg, almost transects Nikumaroro), however no proof to date that he did in fact have such a plan already charted. We also do not know what information (if any) that FN had about the Phoenix Islands, other than a general knowledge that they probably were not or only very sparsely populated. (Lambrecht was quite surprised to find that Hull Island was inhabited upon his fly-over.) Admittedly, from a distance v. fuel consumption basis, the Phoenix Islands are wthin a 400 mile radius of Howland, while the Gilberts are between 500-700 mile radius, making Phoenix the more fuel efficient objective & of course the SE leg of the LOP pointed in that direction. However, we must remember that we have no proof that AE ever _received_ any of the radio transmissions from Lae or Itaska, except for the long ...AAAAAAA ... transmission on 3105 & even then not enough to get a 'minimum' bearing. Therefore, having presumably received no outside communcation from takeoff at Lae until the long...AAAAA... (upon which she was unable to take a bearing) she had no assurance that Itaska would be in any position to find them, whatever direction they chose to go, & since they had already failed to find the Howland landfall, which direction to choose?... SE toward the Phoenix Chain on the LOP, which was closer, with at least a _possibility_ of finding a safe landing place for her Electra (with no certainty they could establish radio contact with Itaska for a rescue from presumably uninhabited islands)... or turn back to the Gilberts, risking a splashdown at sea, (after they ran out of fuel) before reaching any of the Gilbert Islands... but with a somewhat greater possibility of being found & rescued within an _inhabited_ Island chain? Given AE's documented love affair with her Electra & her determination to complete the flight, plus the fuel consumption estimates which would almost insure a ditching at sea if they headed back to the Gilberts, I'm still of the _opinion_ she would have chosen the risk of reaching an uninhabited island in the Phoenix Chain & hoping to save her aircraft, as opposed to turning back to the Gilberts, with the certainty of losing her plane even though the likelihood of being rescued might have been greater near an inhabited island group with some radio availability.... But, we weren't there & we didn't have to make that very tough decision, so until we find the remains of the Electra &/or its crew, we continue to suppose & speculate, which is probably why most of us continue to follow the quest on this rather remarkable forum. Don Neumann From Ric You don't undertand the navigational situation. AE and FN didn't know where they were except that they were someplace on the LOP and fairly close to Howland. Running down the line was the only course of action that stood a good chance of bringing them to land - maybe to Howland, maybe to Baker, maybe within sight of Mckean, maybe to Gardner. Turning back for the Gilberts would mean abandoning the LOP --- their only lifeline ---- to take a blind shot at widely scattered islands that were at the extreme end of their most optimistic fuel reserve. Suicidal. |
The other approach to the TIGHAR hypothesis method is to try and prove this particular hypothesis is wrong (the null hypothesis method). I've been using this approach since 1992 without success. What that means is I cannot state categorically that TIGHAR's hypothesis is wrong. Consequently, further work along this hypothesis and its negative should continue until one can reach a definitive conclusion, which is an individual decision. I can't reach my personal decision as yet. From Ric That's not my understanding of what a "null hypothesis" is. A null hypothesis is not simply saying that a given hypothesis is wrong. That's not a hypothesis at all. It's just gainsaying. If the TIGHAR hypothesis is that the body of evidence thus far amassed is the result of the Earhart/Noonan flight ending at Gardner Island, the null hypothesis would be that the body of evidence thus far amassed has been misinterpreted or can be better explained by other events. That's what Randy has been trying to do without much success for about eight years now. Nobody is going to "prove" that the flight did not end at Gardner unless they find the airplane (or an AIA) someplace else, just as we are not going to "prove" that it did not go down at sea, get captured by the Japanese, or get whisked off to Alpha Centuri unless we find an AIA on Gardner. However, the greater the preponderence of evidence becomes that the flight ended at Gardner, the more widely accepted the hypothesis will become. Conversely, the emergence of credible evidence to support the null hypothesis would cause reasonable people (and me too) to reject the idea that Earhart and Noonan reached the island. What keeps me going is that it's not a matter of balancing the evidence that suggests a landing at Gardner with the evidence that something else happened. There IS no evidence that something else happened. We've repeatedly seen that attempts to show evidence that they were captured by the Japanese or that they crashed at sea fall far short of any acceptable standard. It would appear that either Earhart, Noonan and NR16020 made it to Gardner or they quite literally vanished without a trace. LTM, |
Oscar Boswell's conclusion that the 20 gal/hr rate quoted in Last Flight is for one engine is absolutely on the mark. To assume that Amelia meant this number to represent total fuel consumption will lead to a serious overstatement of Electra endurance. A 10 gal/hr per engine fuel consumption rate is not feasible for the S3H1 Wasp for the stated conditions. I just ran a calculation using Kelly Johnson's recommended maximum range power setting parameters. The assumptions made for my calculation were: Engine rpm = 1600
rpm The calculated result is 40.3 gal/hr for two engines. There is no doubt that Amelia's number of 20 gal/hr represented one engine. From Doug Brutlag The Pratt & Whitney R-985 engine in my AT-7/SNB-5 burns 22-25 gallons per hour roughly at 60% power(give or take 5%) The R-1340 engines in AE's Electra would burn the same or slightly more although if she pulled the prop RPM's back to the lowest limit she could lean the mixtures some more and with a slight power reduction get the fuel flows back to 20 GPH-that's per side folks X 2 motors! Kelly Johnson's figures are entirely consistent with that scenario making the 24 hour endurance figure highly logical & plausible. If AE said 20 gallons she HAD to have meant 20 gallon per side/hour. On another note, is Elgin Long planning on trying to recover this target or whatever from the bottom of the Pacific? Doug B. #2335 From Ric If that's correct then Oscar's observation is quite valid....Earhart "throttled back" to achieve a fuel burn that was GREATER than what Johnson said she should be getting at cruise. Something is weird here. Elgen Long can't check out the target found by Timmer and the Treasure Hunters because he doesn't know where it is and they ain't about to tell him. Besides, as far as anyone knows at the moment, Long and Nauticos (the search technology company he's working with) aren't going anywhere because they don't have any money. Timmer and the boys claim to be going back out in May but they're a group of wealthy "investors" who are spending their own money. God bless 'em. It's good for the economy. From Alan Caldwell I thought her IAS was to be about 150mph or about 130kph. If that is correct (it's been a long day so this is off the top of my head without looking back at anything) then dropping back to 120mph (her guage was in MPHs) is a 20% reduction in airspeed or is my math bad? I also thought that a rough rule of thumb on fuel consumption was about 38gph and I assumed that was total not per engine which makes 20gph not make sense if it is per engine. I have trouble believing, although wiser ones may prove me wrong, that there is a direct proportion between indicated airspeed and gph, meaning a 20% reduction of AS would not mean a 20% reduction in gph. I don't know, without a fuel chart for the electra, what a power setting that would produce 120mph IAS would give you for ghp. Finally, why would she report only what one engine was doing? Usually one wants to know how much gas the plane is using not what just one engine is using. Alan, #2329 From Ric Like I said, something is weird here. Doug feels 20 GPH per side is a very low number attainable only by extreme measures, and yet Johnson said that she could get 19 GPH per side (38 total) and that the numbers should run a little UNDER what he predicted and that she could improve them further in the vent of EXCEPTIONAL headwinds by leaning the mixture further. Let's recall that all she wrote down was: "We are throttled down to 120 indicated airspeed so not to arrive in darkness. We are burning less than 20 gals. of gas at 10,000 ft...." As Oscar and Birch have shown, that has GOT to be 20 gals. each side. What is wierd about it is if she was following Johnson's recommendations (and especially with Mantz sitting right there that would seem to be a valid assumption), prior to "throttling back" she should have been carrying 24 inches at 1600 RPM which should have delivered 150 mph TAS and 38 GPH. She wants to slow down so that she doesn't arrive before daylight so she pulls the power back some unknown amount to achieve --- what? --- a six mph reduction in TAS? Big deal. And then she comments that "we are burning less that 20 gals. of gas" like that is less than they were burning before. That just doesn't make a lot of sense, but I think that the key to understanding what's going on is in what AE would not admit in her notes. According to the Army's report on the Luke Field accident, upon the airplane's arrival at Wheeler Field that morning Mantz said that the prop on the starboard engine had frozen in fixed pitch for the last six hours of the flight. An inspection later showed it to be siezed due to lack of lubricant (and the other prop was about ready to go also). There was no leak found. The props simply had not been properly lubricated to begin with. How would Mantz know that the prop was frozen unless he had tried to make an adjustment? Why would he make a prop adjustment if not to comply with Johnson's table? In other words, for at least the last six hours of the flight they were not able to comply with Johnson's recommendations and were therefore not able to get the predicted results. With one prop frozen in pitch they had to keep BOTH props at an unnecessarily high RPM or endure a very annoying out-of-synch situation. Hence Earhart's implication that "throttling back" improved the rate of burn. It's not an indication that she had a cavalier attitude toward Johnson's recommendations. It's just another example of AE covering her mistakes. LTM, |
> It's pretty clearly
per engine because a 4 or 6% reduction in airspeed It's just not that simple. You can reduce the fuel consumption in an Electra 10E (or any aeroplane) by simply changing the manifold pressure, and leaning the mixture. You can also decrease it by reducing the throttle setting, with much more effect on airspeed. The airspeed is secondary to a pilot, as it is affected by almost everything. Its only relevance is that is keeps the airplane in the air and it is needed to navigate. (Work out when you MIGHT arrive at a destination).
So for a constant RPM I can get about a 11% decrease in fuel consumption without even touching the throttle. (I don't have airspeed settings for these figures --- TIGHAR hasn't posted them).. But they would make VERY INTERESTING READING in the context of the fuel/range thing. By dropping the RPM from 1800 to 1600 and the Manifold Pressure from 28" to 24" (and tweaking the Cambridge "mixture" control) we can pick up 33% decrease in fuel consumption. Now here's where it would help to have the Airspeed for each of these settings. However, as I suggested before, the pilot is primarily interested in the Fuel consumption and the engine condition and performance. The Navigator is primarily interested in the Fuel Flow AND the Endurance AND the Air Speed AND the Time (among other things.) From this he calculates the Endurance, Ground Speed, Range etc, and passes them to the Pilot, who then adjusts the engine settings to bring them back within the required performance envelope. "Wire from Marshall confirms my recommendation.... 'Nine Hundred gallons Fuel 'Ample' for Forty Percent Excess Range to Honolulu for conditions given in wire this morning' " If the 40% excess range was what we pilots call "reserve", it would be also interesting to find that 900 Gallons was considered sufficient to travel 2925 Nautical Miles in the Electra. On that basis, 1150 gallons should have given a range of perhaps an extra 6.5 hours at 130 Mph (118Kts? My trusty CR-2 is at the Airport.). That's like 770 Nautical Miles! Total range = 3695 Nautical Miles Obviously the 40% excess range was NOT reserve. Under normal conditions the Electra appears to have been "expected" to burn 900 Gallons in 21 hours/ 2090Nm. With 1150 Gallons that still gives 4 hours in the tanks after 21 hours "At Economical Cruise". This was qaulified with "Should run a little UNDER figures given". This was not a Best Case Scenario, it was sensibly conservative. Further "If Necessary Mixture Can Be Leaned "(further)" on last half (1000 Nautical Miles) of flight if "Exceptional" headwinds exist. NOT If "Headwinds" exist, but If "Exceptional Headwinds" exist. The more I go over this the more interesting it is.
In a sample of Finch's flight over the entire distance, she got under 100kts 4 times:
65kts with a 30kt wind gusting! Now if that happened over the entire Earhart Lae --- Howland segment? Hmmm Even so, for that entire segment, the average speed for the 22hrs involved was 85kts and covered 1923Nm. At that rate Earhart would have taken 26hrs to get to Howland... The average speed for the whole flight was 119kts, and leaving out the under 100kt segments (which for statistical porpoises we cannot do) it would have been average of 131kts. Obviously for various reasons, the trip could take lots of time. From the above, a "likely worst case" scenario could put the Electra at 100kts for about 22hrs solid. That still gives us about 200 gallons at Howland after 22 hours in the air. We know she was close at 19hrs, but even so. 200/35gph = 5hrs flying time AFTER 22.25hrs at an average 100kts GS. Earhart didn't run out of fuel.... Well, not at Howland anyway. (I know... She ran out of fuel at Howland. It's just that I cannot find ANY evidence in my limited capacity as a pilot, or my pretty loose capacity as a navigator that convinces me she ran out of fuel anywhere near Howland). RossD |
Recent discussion has referenced the L-10 cruise fuel consumption of 38 gph vs. the "loiter" or (assumed) maximum endurance fuel flow of 20 gph. In this case, Maximum Endurance was 47 percent of Long Range Cruise. The nearest example for which I have BOTH max. endurance and LRC data is the C-119G. Comparing a mid-gross weight LRC to a relatively light gross weight max. endurance yields a fuel flow reduction of 45 percent. 20 gph passes the test of reasonableness. Skeet Gifford From Ric Trouble is, the implication is that she can maintain altitude at 10,000 feet and 120 mph on the clock at whatever power setting she's using. |
At about 18:07:54 GMT, the Sun Line across Howland (using its correct coordinates) also ran across Gardner. At that time the Sun's computed height at both islands was 4 deg 20 min. By 1900 GMT, the Sun Line then across Howland passed 7 miles NE of the Gardner coordinates. At 2000, 2100, 2200, and 2300 GMT the Sun Lines for Howland and Gardner were 29, 67, 135, and then 244 nm apart. (The spread between the LOPs accelerated as the Sun's subpoint neared). These are the uncorrected heights I am getting for the Sun that morning: Howland 1800 GMT: 02 deg
31 min Gardner 1800 GMT: 02 deg
33 min The Sun's guidance would be valuable in attempting to track across either island. For a while around 18:08 GMT the two islands shared the same Line. Earhart's flying SE on the 157-337 LOP predicated on Howland's coordinates would trend her along toward Gardner at first; but Sun sights alone would not give guidance along that direct route to Gardner; adherance to it would not lead to Gardner. Once Howland was assuredly left behind, alternating to Gardner would require eventually computing new Sun Lines based on Gardner's coordinates, and making the LOP interception sooner or later. With an unrealistically fast plane, then the 157-337 LOP would be sufficient; Gardner would shortly be reached with course guidance from Sun shots reliably based on the Howland coordinates. But because in actuality hours would elapse, the 157-337 LOP wouldn't be workable indefinitely. Of course the 157 great circle course to Gardner would still be there, but the Sun's azimuth would no longer be perpendicular to it. The shorter, direct 157 course could be flown, using cross LOPs, but it wouldn't be the same as running down the Sun Line. [--One thing about these celestial LOPs. The accuracy of tracking the LOP wouldn't diminish with distance. Neither distance from the assumed position, nor distance from the subpoint should ordinarily affect accuracy much. It is not like a fan-shaped course widths from radio ranges. The LOP doesn't fan out. Its radio navigation counterpart is the DME arc--an arc of constant distance]. Mark Prange From Ric Aren't we making this too complicated? Noonan gets the 157/337 LOP at or near sunrise, advances it through Howland, gets to the advnaced line and --- damn --- no Howland; runs 337 for as far as he dares then turns back to 157 and sticks with that because he knows it will eventually bring him to some island. As the morning progresses the sun moves and eventually he can get a reliable "cut" across the original LOP. He finds out that he's well south of Howland --- too far to turn back. He starts watching for Gardner and eventually it appears. |
The Johnson cruise tables are consistent with early WW II military cruise tables that I have seen, but these lack the detail of graphs produced for later-generation aircraft. Ric has a copy of a comparison I did between a C-47 and L-10. Both have similar wing loading and similar power-to-weight ratios. From this comparison, it is clear to me that the 130 ktas, 38 gph numbers are VERY CONSERVATIVE when applied to the end of the flight when the airplane had burned off much of its fuel. Earhart had three (reasonable) choices toward the end of the flight: 1) Maintain 130 knot True Air Speed (TAS) which would necessitate reducing power and re-accomplishing the leaning procedure. 2) Keep power constant at 38 gallons per hour and accept increasing speed as the airplane got lighter. 3) Reduce BOTH speed AND power. While this would have been the best choice in terms of Air Nautical Miles per Pound of Fuel, there is ZERO evidence that she did this. 4) Well, there is a fourth choice that would make the Longs happy. She INCREASED both power and speed in a suicidal attempt to make the eleven o'clock News. Sorry, Ric, I got carried away.p The bottom line--I don't think we can make reasonable estimates of Maximum Endurance fuel consumption near the end of the flight from tables that are probably mid-point numbers. We have to take her word for it. Skeet Gifford |
Last night I gave a talk to a local bottle collecting club ("Can There Be Peace Between Bottle Collectors and Archaeologists?" with a brief additional topic: "Amelia Earhart and the Missing Benedictine Bottle"). The club gives its speakers bottles as tokens of its appreciation, so I am now the proud owner of a Benedictine bottle that the club's experts figure dates from the 1920s or 30s (though possibly as late as the 40s). It's brown, 26 cm. (10") high, 9 cm (3.5") in base diameter, 10 cm (4") in shoulder diameter, with a neck that tapers from4 to 2.8 cm (1.5-1") and a lip diameter of 3.5cm. (1.5"). The lip is sort of crenelated, with opposing indentations that look like they'd accommodate a clasp-type cork, but it's now sealed with a regular cork (the club thought it probably not original) with a plastic top bearing the imagine of a monk and the words "Sic.Prior.SScs Trinitatis Cong. S. Mavri" and "Pat PV 645596 S Benedictvs." The shoulders are embossed "Marque Deposet", "Benedictine," and "B and B". It has paper labels in French identifying it as "B and B Produit de la Benedictine S.A. Fecamp (France)," etc. It looks like it would hold about a liter of the beverage of a castaway's choice, but the cork is stuck so I couldn't find out for sure. No sign of little corks on chains. The neck is such that it would be easy to tie a piece of twine around it and hang it over one's shoulder, neck, or other convenient appendage for transport. There. Primary data. LTM (who regrets
her sometimes anal retentive offspring) From Ric Mon Dieu! You are lucky, no? The most significant thing I see here is confirmation that, just as today, Benedictine bottles had the name embossed into the glass, thereby explaining how Wernham knew it was a Benedictine bottle and making it seem likely that Gallagher never saw it before Koata split for Tarawa with it. |
I personally enjoy the discussion of range and endurance very much --- but we already know as much as we are ever likely to know about the time of fuel exhaustion. We know that using Johnson's settings and 1100 gallons, the plane should have stayed aloft for 24 hours. We know that leaning and power reduction tecniques can affect endurance significantly. Taking Johnson's figures as "standard", we can expect a variation of as much as 5 to 10% in endurance depending upon the exact power management techniques applied and the care given to leaning. Applying that range of variation yields a possible endurance of anywhere from 22 hours to 26 hours . As Ric pointed out earlier, Johnson's recommendations were simplified, and were not designed for absolute best range performance. Other techniques were possible. For example, Strippel claimed that Paul Mantz plotted power reduction curves for AE's use. The technique for using such curves (as anyone who remembers Max Conrad knows) is to fly at a constant airspeed, gradually and continuously reducing power as fuel burn lightens the plane and tends to increase the speed. In Johnson's plan airspeed would gradually increase during each 3 hour period, as the plane lightened, and then be brought back to the desired figure with the scheduled power reduction. In the initial 3 hours of cruise, for example, fuel would be burned at 60 gph, for a total of 180 gallons. If one flew a power curve instead and held airspeed constant by continuously reducing power, fuel burn would gradually decrease during the same three hours. Extrapolating from Johnson's figures, we might assume that near the end of the third hour of cruise, fuel consumption would have decreased to slightly more than the 51 gph setting Johnson called for at the beginning of hour 4. We might guesstimate that the fuel burn would average perhaps 60-57-54 gph for the three hours, for a total of 171 gallons (about a 5% reduction). In hours 4 through 9 of cruise, we might expect something on the order of 51-48-45-43-41-39. Over the 9 hours, this is a saving of about 32 gallons (or about 7% off Johnson's figures). Similar reductions would take place in the remaining hours of the flight if the procedure were continued. Even an overall 5% reduction in fuel consumption equals an additional 1 1/2 hours endurance (with some reduction in average airspeed). As Ric also noted, Johnson advised more drastic leaning if unsual headwinds were encountered, suggesting that a setting of 0.70 be used instead of 0.72 - one assumes that this equates roughly to an additional 3% reduction in fuel consumption. Strippel (p.115 ) quotes Mantz as suggesting a final setting of 0.65, indicating even more drastic leaning, and says that Mantz' procedures were intended to yield an endurance of about 28 hours with full fuel (say 26 hours with 1100 gallons). That being said, the reverse is equally true --- failure to follow the power management/leaning procedures rigorously could have caused a 5% or more increase in fuel consumption , and other factors (reduced fuel density, venting, underfilled tanks, malfunctions in instruments, prop problems, etc.) could have reduced endurance to 22 hours (or even to 20+30). If, for example, AE simply failed (or refused) to make the last power reduction called for by Johnson (from 43 gph to 38 gph) that alone would have cost her about 1 hour and 45 minutes endurance (albeit with some increase in airspeed). It's speculative to suggest that she did that. But both Peter Garrison (in "Long Distance Flying") and Louise Sacchi ( in "Ocean Flying") have remarked on the psychological difficulty of continuously reducing power to gain maximum range. The most sensible assumption is that AE tried to follow Johnson's figures as closely as possible. Certainly she seemed to be following them on the South Atlantic crossing (which is the only other leg for which Last Flight gives any detailed information). She wrote (page 76) that she was "5 1/2 hours out" and "indicated our speed 140 at 5780 feet. Man. press. 26 1/2 rpm 1700." This corresponds to Johnson's 3/11/37 telegram instructions for cruise at 6000. An indicated airspeed of 140 at 5780 feet is roughly equal to a TAS of 156. In any case, we don't know --- and will never know --- when fuel was exhausted. If everything went wrong(as it sometimes does) fuel could have been gone at 20+30. All we can say is that the Electra probably could have reached Gardner in the absence of any equipment malfunctions or extreme deviations from normal fuel management procedures. From Ric I agree. |
When a smoking gun is found, and let's say it's a tooth or bone fragment with a DNA match, what then? Does TIGHAR declare victory, close the Earhart file and move on to the next project? The publicity would certainly add to TIGHAR's coffers, but would you use the money to go back to Niku? There will certainly be questions that will not have been answered yet, but if the basic mystery has been solved, how much further do you go, and why? Darrell Houghton From Ric A "smoking gun" (Renaud --- what would that be in French?) would be the beginning, not the end, of solving the Earhart riddle. Nikumaroro would cease to be just one more place where people look for Amelia Earhart (Saipan, New Jersey, the bottom of the ocean) but would become an archaeological site to be examined for any clue that might help us piece together the rest of the story. A smoking gun would mean that the story of what really happened to Amelia Earhart is infinitley more dramatic and tragic than anything that the most imaginative conspiracy buff ever cooked up. I can easily see another 5 to 10 years of work before we could be sure that everything that could be known is known. Why do it? For the same reason we're doing it now. As an exercise and training ground in how to discover historical truth. LTM, |
I believe some perspective may be helpful in trying to relate Amelia's 20 gph notation to Kelly Johnson's finding of 38 gph at a specified power setting. As I and others have pointed out, 20 gph for two engines is not realistic. One then reasonably asks, as you have done, why at a throttled condition would total fuel consumption apparently exceed the 38 gph (19 gph per engine) number given by Johnson? There are a number of factors to explain this apparent incongruity regardless of who was riding in the right seat: 1. "Throttled down" is a qualitative phrase. It does not tell us mixture ratio, rpm or manifold air pressure. All we really know is she was not at wide open throttle. 2. We have assumed (at least I did for my calculation) that she went to a fuel/air ratio of 0.070, the lowest ratio Johnson mentions. (She could well have maintained the slightly higher 0.072 ratio.) I did this intentionally to obtain the most optimistic result with the data at hand. 3. For greatest fuel economy and only if necessary, Johnson recommended adjusting mixture ratio slightly to 0.070. Note that he did not alter engine rpm and manifold air pressure. These remained unchanged from the power setting designed to achieve about 38 gph. The lower mixture ratio would increase cylinder head temperatures somewhat, but still marginally acceptable under most conditions. 4. Fuel consumption is very sensitive to the supercharger pressure recovery a nd heat gain of the air/fuel mixture in the intake manifold pipes. These factors vary non-linearly with changes in engine rpm. Relatively small changes will result in very perceptible variations in fuel consumption for a given power setting, easily accounting for the difference between the approximately 38 and 40 gph numbers in question here. 5. Once again, remember that the numbers given to Amelia by Kelly were based on a standard atmosphere. One thing we can be pretty certain of is that she was not flying through a standard atmosphere. For the above reasons, there is nothing incongruent (weird?) about Amelia's 20 gph (per engine at a presumed 0.070 mixture ratio) notation, relative to the 19 gph figure measured by Kelly at a 0.072 mixture ratio. One must accept Kelly Johnson's numbers as nominal values, not absolute. They were perfectly acceptable for planning the takeoff fuel load for a given flight. It is also important to remember there is a tolerance associated with any measured number. Similarly, Amelia's 20 gph number is an approximation, and almost certainly less accurate than corresponding values measured by Kelly during his flight test program. Rather than be concerned with an apparent disparity, I view the 20 gph notation as being remarkably consistent with Kelly's work. This is the only instance where we have confirmation of predicted data during any of her flights, at least to my knowledge. From Ric To clarify my previous posting, Earhart's notation looked "weird" to me UNTIL I remembered that the airplane had a significant mechanical malfunction during the last six hours of the flight which would adversely effect the crews ability to follow Johnson's recommendations. |
You asked: "I haven't seen the Cal-Tech analysis. What is the Cal-Tech analysis? Have you seen the Cal-Tech analysis? Who did the Cal-Tech analysis? Who paid for the Cal-Tech analysis? What assumptions did it start with?" I have seen the Cal-Tech analysis. It is an analysis of possible fuel consumption by AE's plane, resulting in possible time aloft ranging between 20:38 minimum and 23:38 maximum. I no longer have a copy in my possession; however, I will endeavor to obtain the names of the authors (I believe that there were two). I do not know who commissioned or paid for it (it may have been an independent research project). With respect to assumptions used, I recall that they used the Johnson information, the Chater report and, I believe, direct source material from Lockheed. Based upon the information you have gleaned from the Forum participants, including Messrs. Pingrey, Caldwell et al., it would seem that the Cal-Tech maximum time aloft, at least, comes reasonably close to coinciding with TIGHAR's assumed maximum range. The Cal-Tech analysis suggests the possibility that time aloft was less. If it was, indeed, less than 23:38, then it would have been a long shot for AE & FN to have reached Gardner. LTM, From Ric Yes, if you could get the names of the authors that would be a big help. Alternatively we could just query the --- what? --- Aeronautical Engineering department? I think that it's important that we find out just what was done. Contrary to your impression, what we're learning about the aircraft's capabilities and about Johnson's figures indicates that our original estimate of about 24 hours is probably on the conservative side. If Cal-Tech was buying Long's interpretation of the Chater Report it's a case of garbage in, garbage out. LTM, |
Let me better explain my "null" hypothesis method. If there was some way I could demonstrate or prove that AE/FN could not have made it to Gardner, then we could rule out the TIGHAR hypothesis. I can't do it, and I suspect no one else can with the available data. That doesn't prove or disprove either hypothesis, though. But my method does offer an alternative and acceptable method of using the scientific approach. I don't know the "official" name of it, but the negative hypothesis or null may be two ways of describing the same thing. Sorry for any confusion. From Ric Okay, I see what you mean. It might be called disproving a hypothesis by the disqualification of a necessary condition ( i.e. the airplane being able to reach Gardner). |
I did some celestial nav activities with Linda Finch in 1996 at the Oshkosh air show and sold her an A-10 model sextant. They wanted to showboat with it-not learn or use it. The engines on her Electra were essentially the same to my knowledge-P & W 1340's. They were built new from a collection new unused parts. At the show though one of the mechanics mentioned that the fuel burn was much higher than it should have been and was causing some concern. I suspect the break-in was not accomplished and that they solved the problem later. I seem to recall that avgas in those days had a higher octane and alot of lead content compared to what is on the market now. They are now trying to get on the market on unleaded avgas that still retains protective octane requirements. The engines would have required much preventative maintenance along the way to retain peak performance so as to get the burn figures calculated by Kelly Johnson-plug changes, valve adjustments, carb settings, oil & filter, etc. I never have run across anything that mentioned maintenance but I know it had to be done or she would never had made it as far as she did. Radial engines will generaly give reliable & faithful performance, but for every hour run them, you have to turn a wrench on them 2 or 3 times that. Finch never did land at Howland as the runways were unusable. She stopped at Tarawa I believe, overflew Howland, and then went on to either Christmas island or Canton, I forget where. She also had the advantage of multiple GPS, and Albatross chase plane, and a REAL pilot and babysitter keeping her out of trouble. Ahh, I'll shut up. Doug B. #2335 |
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