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Author Topic: Lockheed Report 487 on the Electra's range and speed  (Read 53449 times)

Martin X. Moleski, SJ

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Lockheed Report 487 on the Electra's range and speed
« on: October 07, 2009, 11:20:51 AM »

New report by C.L. Johnson (June 4, 1936) up on the website.

Required reading for anyone who wants to estimate the aircraft's theoretical range.

Beautifully done--37 pages!

                Marty
LTM,

           Marty
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Jay Burkett

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Re: Lockheed Report 487 on the Electra's range and speed
« Reply #1 on: July 20, 2010, 12:30:26 PM »

Marty,

You are right this is well done.  Is a scan of the original available?  Having been using old aerospace engineering reports for some time I don't readily trust transcriptions!  It is too easy to make a mistake!

Jay
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Martin X. Moleski, SJ

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Re: Lockheed Report 487 on the Electra's range and speed
« Reply #2 on: July 20, 2010, 04:58:56 PM »

You are right this is well done.  Is a scan of the original available?

Not that I know of.

All that Pat said was that the transcription came from a microfilm.

Quote
Having been using old aerospace engineering reports for some time I don't readily trust transcriptions!  It is too easy to make a mistake!

If you see something that looks wrong, you could ask about it.  Politely.  I'm not sure how the transcription was made.  I've been pleasantly surprised by some recent things I did with Optical Character Recognition.
LTM,

           Marty
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Jay Burkett

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Re: Lockheed Report 487 on the Electra's range and speed
« Reply #3 on: July 21, 2010, 02:44:11 PM »

Marty,

No.  I'm just curious.  The graphs just looked a little too clean!

I guess I've been burned one too many times with transcribed data!  I have to be care or the old curmudgeon engineer starts to come out!

Thanks for the quick reply!

Jay
Jay Burkett, N4RBY
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Martin X. Moleski, SJ

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Re: Lockheed Report 487 on the Electra's range and speed
« Reply #4 on: July 21, 2010, 03:11:34 PM »

No.  I'm just curious.  The graphs just looked a little too clean!

Understood.  I don't know how Pat produced them.  They are a work of art!

Quote
I guess I've been burned one too many times with transcribed data!  I have to be careful or the old curmudgeon engineer starts to come out!

The concept of "reasonable doubt" suggests that there may also be "unreasonable doubt." 

My guess is that Pat faithfully reproduced the graphs as published by Lockheed.  I presume that the new charts look a lot like the old--and are not data sets plotted from experiments but theoretic curves that give a general idea of performance.  That they are "too clean to be true" is not Pat's fault but Lockheed's.
LTM,

           Marty
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Bill Lloyd

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Re: Lockheed Report 487 on the Electra's range and speed
« Reply #5 on: July 21, 2010, 09:31:12 PM »

Lockheed Report 487, June 4. 1936, is  a very thorough and well written technical report. In addition to the assessment that report 487 is merely a marketing document, it is also a procedural guide that contains numerous recommendations for operation of the 10E.  It is very similar to operations and specifications manuals that I have had to study and master over the years while transitioning into larger and more complex aircraft.

In regards to range and fuel consumption, the argument advanced that Earhart used excessive fuel en route to the LOP  because the Cambridge Exhaust Gas Analyzer malfunctioned,  is not convincing.  The evidence put forth to support that claim is very lame and does not even rise to the level of circumstantial.

The apparent function of the instrument was to enable the pilot to precisely lean the fuel mixture for each engine. Specific Cambridge settings were calculated by Lockheed and provided to Earhart.  Notwithstanding, she should have been able to lean the mixture without the instrument and if failure of the instrument did occur, she surely would not have ignored the leaning procedure. 

Lockheed Report 487, Model 10E, page 3, specifies “Watch the mixture closely at all times. The engines must be run very lean,” “in climb when the power output is increased, check the mixture,“ and on page 5 and page 9, “WATCH MIXTURE AT ALL TIMES”.

Most of my flying  has been with turbine engines but I do recall that in flight school while flying with piston engines, we were taught how and when to lean the fuel mixture by observing the RPM. If you lose instruments, either attitude or engine instruments, there are always options.  Maybe in 1937, this was not the case.

In regards to the report by Earhart that she was flying at 1000’ altitude when on approach to Howland, not only was this so she could see the island, this let down procedure is specified in Lockheed Report 487, page 3, “When about 100 to 150 miles from the end of the flight, put the ship in a power glide losing about 250 to 300 feet of altitude per minutes while maintaining cruising power output.”

The fact that it appears that Earhart may have been trying to follow the procedures and recommendations of the manufacturer in this complex and technical report, indicates that perhaps, other than radio procedures, she might have been more astute in her approach to flying the aircraft than she has been given credit for. Perhaps not!
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Ashley Such

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Re: Lockheed Report 487 on the Electra's range and speed
« Reply #6 on: July 21, 2010, 10:09:08 PM »

Very intersting! Thanks for sharing the link, Marty! :)
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Martin X. Moleski, SJ

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Re: Lockheed Report 487 on the Electra's range and speed
« Reply #7 on: July 21, 2010, 11:24:30 PM »

... The fact that it appears that Earhart may have been trying to follow the procedures and recommendations of the manufacturer in this complex and technical report, indicates that perhaps, other than radio procedures, she might have been more astute in her approach to flying the aircraft than she has been given credit for. ...

After the disaster at Luke Field, which certainly calls her abilities and judgment into question, AE flew 29 legs of her journey around the world without further mishap. 

Her takeoff from Lae was masterful and took a huge amount of courage.  AE stayed calm while the plane descended from the bluff at the end of the runway back into ground effect.  She held steady at low altitude until the plane disappeared in the distance and eventually got up to her planned cruising altitude.  If even one of the post-loss radio messages is real, that means that she brought the plane down safely on her last flight. 

If courage and stick-and-rudder skills were all that were needed to complete the journey, she would have made it.
LTM,

           Marty
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Erik

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Re: Lockheed Report 487 on the Electra's range and speed
« Reply #8 on: July 22, 2010, 02:00:48 PM »

In regards to range and fuel consumption, the argument advanced that Earhart used excessive fuel en route to the LOP  because the Cambridge Exhaust Gas Analyzer malfunctioned,  is not convincing.  The evidence put forth to support that claim is very lame and does not even rise to the level of circumstantial.

The apparent function of the instrument was to enable the pilot to precisely lean the fuel mixture for each engine. Specific Cambridge settings were calculated by Lockheed and provided to Earhart.  Notwithstanding, she should have been able to lean the mixture without the instrument and if failure of the instrument did occur, she surely would not have ignored the leaning procedure. 

Good point.  I agree completely. 

Following procedures would have provided nearly the same exact results as the instrument.  After all, that's how procedures are derived in the first place - from instruments like this.  Instruments are simply redundant backups to make sure procedures are being followed correctly. 

One could even argue that because of the instrument failure, she would have paid even more attention to the proper procedures.

In other words, the instrument failure itself is not a convincing argument without evidence that AE also failed to follow procedures.  I would say that she was keenly aware of the consequences resulting from not properly leaning the engines.  Which adds more credence that she would not have ignored those procedures.  Engine temps would certainly have been one good clue.  Even with her past mistakes, it's hard for me to buy that argument.  Possible - Yes, Probable - No.
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Ted G Campbell

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Re: Lockheed Report 487 on the Electra's range and speed
« Reply #9 on: July 22, 2010, 06:47:05 PM »

All,

It would be interesting to visit the flight profile of AE’s around the world flight and compare that to the Johnson report as what to do.

We know the distance, time, and target airport on each leg.  We also have some (maybe all up to the final refueling) how much fuel she put on board for each leg.  A little mathematics should show whether or not AE was following the recommendations of Johnson or was she winging it.

Ted Campbell
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Martin X. Moleski, SJ

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Re: Lockheed Report 487 on the Electra's range and speed
« Reply #10 on: July 23, 2010, 08:27:16 AM »

> ... We also have some (maybe all up to the final refueling) how much fuel she put on board for each leg.  ...

That doesn't ring a bell.  Have you got a link to that data?

We do have the distance for each leg.  It may be a theoretical distance derived from maps rather than actual distance made good on the flight, which could introduce some errors into the calculations.
LTM,

           Marty
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Robert J Schafish

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Re: Lockheed Report 487 on the Electra's range and speed
« Reply #11 on: October 10, 2010, 07:32:29 PM »

Montaro Product Development Services modeled the performance of the Electra 10E using the Kelly Johnson and W. C. Nelson 1936 report. They also reference TIGHAR in the intro.   Here is a link to the pdf of their report.  Don't know if their model is available for use by others.


http://www.mantaro.com/downloads/Electra_10E_Model_Amelia_Earhart.pdf
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Martin X. Moleski, SJ

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Re: Lockheed Report 487 on the Electra's range and speed
« Reply #12 on: October 10, 2010, 09:59:57 PM »

Montaro Product Development Services modeled the performance of the Electra 10E using the Kelly Johnson and W. C. Nelson 1936 report. They also reference TIGHAR in the intro.   Here is a link to the pdf of their report.  Don't know if their model is available for use by others.

http://www.mantaro.com/downloads/Electra_10E_Model_Amelia_Earhart.pdf

Thanks for the link, Robert.  I think I met David and saw a demo of the simulator.  We talked a little bit about how to do a web-accessible version.  That was a few years ago, I believe.
LTM,

           Marty
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Mike Colleran

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Re: Lockheed Report 487 on the Electra's range and speed
« Reply #13 on: December 30, 2010, 09:32:23 AM »

What a great find.  Thanks for all the great resources, Ric--and everyone associated with this site (and cite!).  The Kelly/Nelson document is certainly a valuable piece of historical info.
  
The first thing that jumped out at me was the typo in the HP required column, p.30--min. gross wt.  That was an eyebrow raiser.  I thought at first it was sloppy work from Kelly and Nelson, but reading this thread, I suspect it arose when the document was transferred from microfilm into Adobe.

Some other comments:

"Complete data on the fuel consumption of the engine was not available so generalized data on aircooled engines was used. (see pg.   )"
 
Report 487, p. 20.

Wow!  That's one hell of a qualification to bet your life on!  Especially since Johnson predicts the big improvement in specific range doesn't occur until 9+ hours into max range flight (see my little spreadsheet attached).
  
I’ve spent paid time in the left seat out over that ocean that makes the Atlantic seem like a river.  If we’re talking flying the Pacific in our L10E, that puts it around our point of no return, assuming a) we’re smart enough to realize we have one,  b) we’ve bothered to figure out where it is, and c) we know what we should check before we go through that particular one-way door.  What happens if we’re on the other side when we discover we can’t get our gallons per hour down below 40?  What are we going to do then, swim back to Burbank to complain? ;-)

The only mention of actual fuel consumption achieved in AE’s Electra that I’ve found refers to the first attempt Oakland-Honolulu segment.  It’s in the posthumous book Last Flight that GP put together from her surviving notes:

 “Daylight comes at last.  The stars fade.  We are throttled down to 120 indicated airspeed so as not to arrive in darkness.  We are burning less than 20 gallons of gas at 10,000 feet.”  (p.37)

She’s surprised they’re burning less than 20gph/engine!  Doesn’t she know she has to get 19 at full throttle for 10+ hours for max range flight??  Not throttled back at 120 IAS with Mantz in the right seat to handle the mixture??  That’s what the remainder line in Johnson’s March 11 telegram calls for.

Maybe she just bought this flat-footed conclusion by the greatest aeronautical engineer of all time:

"(1). It is possible to fly a Lockheed Electra Model 10E non–stop for a distance between 4100 and 4500 miles starting out with 1200 gallons of gasoline and the proper amount of oil."

She certainly never seems to have bothered to do this:

"(3). The Cambridge Gas Analyzers should be carefully calibrated in flight to see if the fuel consumption data used in this analysis can be obtained. This should be done before attempting any long range flight."

What's the max range anybody ever flew an L10E and lived to tell the tale?  Any record out there?
  
I just wonder how many of Kelly’s 4,100 to 4,500 miles were on marketing fumes.  
« Last Edit: December 30, 2010, 10:46:12 AM by Mike Colleran »
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pilotart

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Re: Lockheed Report 487 on the Electra's range and speed
« Reply #14 on: December 31, 2010, 12:34:49 AM »


"(1). It is possible to fly a Lockheed Electra Model 10E non–stop for a distance between 4100 and 4500 miles starting out with 1200 gallons of gasoline and the proper amount of oil."

She certainly never seems to have bothered to do this:

"(3). The Cambridge Gas Analyzers should be carefully calibrated in flight to see if the fuel consumption data used in this analysis can be obtained. This should be done before attempting any long range flight."

What's the max range anybody ever flew an L10E and lived to tell the tale?  Any record out there?
  
I just wonder how many of Kelly’s 4,100 to 4,500 miles were on marketing fumes.  

When we look at the published maximum range of any aircraft today, it will be based on a 'ferry' flight with ideal conditions, minimum load and maximum fuel and will include landing with enough fuel remaining for a 'VFR' or 'IFR' Reserve Fuel remaining or even a 'NBAA' calculation to include a diversion to an alternate, plus a reserve.

In 1937; the "It is possible to fly..." range statement meant to dry tanks under ideal conditions and you were expected to subtract your landing reserves and diversion to alternate from that number.  Otherwise you would most certainly be running on "Marketing Fumes" :)

Prior to Amelia's unfortunate last flight; in May 1937, H.T. "Dick" Merrill and J.S. Lambie accomplished a round-trip crossing of the Atlantic Ocean; this feat was declared the first round-trip commercial crossing of that ocean, and it won them the Harmon Trophy. On the eastbound trip, they carried photographs of the crash of the Hindenburg, and on the return trip, they brought photographs of the coronation of King George VI.  

They also flew a Lockheed 10E and theirs was probably the only other "Special" version produced by Lockheed with all those huge ferry tanks installed and higher gross weight allowed.  Those 3,465 Statute Mile Great Circle Routes no-doubt proved that the Lockheed 10E Special had the range needed for Amelia's Flight Plans (even including a diversion to Gardner Island).

It is ironic how Amelia, due to her tragic and completely avoidable loss is exceeded in fame only by Lindbergh and the Wright Brothers, way ahead of Doolittle, Merrill, Rickenbacker and so many other far more notable Aviators.

Merrill was also featured in a 1937 Film "Atlantic Flight' based on and with footage from his Lockheed Trans-Atlantic Flights.

Merrill had previously (September 1936) crossed the Atlantic, 'First Round-Trip'; in a single engine Vultee V1A (with millionaire singer Harry Richman, famed for Puttin' on the Ritz), this had been the "Ping-Pong" flight.  In modifying the Vultee for the trip, the most modern equipment was sought out by Merrill, including the Hooven Radio Direction Finder (licensed to Bendix). It was Richman's idea to fill empty spaces in the wings and fuselage with 41,000 ping pong balls, which it was hoped would allow the aircraft to float if it was forced down in the ocean.

Art Johnson
 
« Last Edit: December 31, 2010, 12:39:52 AM by pilotart »
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