TIGHAR
Amelia Earhart Search Forum => Aircraft & Powerplant, Performance and Operations => Topic started by: Travis Nutsch on February 11, 2023, 09:49:40 AM
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Just double checking. Are the figures from the 487 Report in nautical or statute miles?
https://tighar.org/Projects/Earhart/Archives/Documents/Report_487/Report487.pdf
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Read the report.
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Hi Ric – Long time no hear.
I would guess that you probably know off the top of your head whether the report is in statue or nautical miles. If so, it would have been just as easy, although probably not as satisfying, to just tell him. Even if you don’t know if they are in statute or nautical (which I find hard to believe), it would have been more civil to say something like, “I don’t know, you’ll have to read the report.” I understand that that there may have been some provocation, perhaps unintentional though.
I searched the document for the terms nautical, knots, and statute, and did not find any of them. Maybe it's not mentioned in the report? I tried reading the report myself but suffered from MEGO after the introduction. I did notice though that the report is missing pages 17, 18, 19, and 25. Is there something going on here? Some kind of conspiracy? ;D ;D I'm guessing that only navigators use nautical, so the report is in statute.
Btw, I was working literally across the street from Gillespie Field in San Diego yesterday. Any relation? Does what’s her name still have an Electra there? What is her name anyway (Grace something)? Is she still alive? Still have the Electra? I get down there a couple times a year, would love to take a peek at it. I know, I could Google it all and find it out myself, but how about a little help, just for old time’s sake? I tried contacting her maybe ten years ago, no response. I remember she had some health problems.
In all seriousness, hope you’re doing well.
Diego
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It's in statute.
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Hi Diego
Grace Mcguire’s Electra was purchased for the new Earhart Museum in Atchinson Kansas that opens later this spring.
https://www.flickr.com/photos/50393882@N00/8931514063
https://ameliaearharthangarmuseum.org/
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Btw, I was working literally across the street from Gillespie Field in San Diego yesterday. Any relation?
As far as I know, the only landmark named after one of my relations is Gillespie Rock (Craig Ghilleaspuig) in the western Highlands of Scotland, but that was in the 14th century.
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Hi Diego
Grace Mcguire’s Electra was purchased for the new Earhart Museum in Atchinson Kansas that opens later this spring.
https://www.flickr.com/photos/50393882@N00/8931514063
https://ameliaearharthangarmuseum.org/
Thanks Matt.
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Thanks Ric. That's probably a bit far for me!
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It's in statute.
The report mentions "air miles" several times which are generally nautical miles.
https://sciencing.com/facts-5832079-difference-air-miles-nautical-miles-.html
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The report mentions "air miles" several times which are generally nautical miles.
https://sciencing.com/facts-5832079-difference-air-miles-nautical-miles-.html
It's confusing. The website referenced says air miles are nautical miles and airlines use statute miles when calculating frequent flyer awards, and yet, if you Google the term "Air Miles" you get only references to frequent flyer programs.
Context is everything. We're talking about the term "air miles" in a 1936 Lockheed report. Lockheed specs published in 1936 list speeds in M.P.H and the "cruising range" for the various Model 10 versions in miles and kilometers, for example "830 miles" or "1340 Kms." Those miles are clearly statute miles.
Report 487 also consistently uses M.P.H. Using nautical miles for range would be mixing apples and oranges. I can't find a reference to nautical miles or knots in any Lockheed document published in the 1930s.
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In air navigation, "Air miles" only refers to the distance traversed through the air before the wind vector is applied. In other words, the "no wind" distance. It does not imply either Statute or Nautical miles.
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It's confusing. The website referenced says air miles are nautical miles and airlines use statute miles when calculating frequent flyer awards, and yet, if you Google the term "Air Miles" you get only references to frequent flyer programs.
Context is everything. We're talking about the term "air miles" in a 1936 Lockheed report. Lockheed specs published in 1936 list speeds in M.P.H and the "cruising range" for the various Model 10 versions in miles and kilometers, for example "830 miles" or "1340 Kms." Those miles are clearly statute miles.
Report 487 also consistently uses M.P.H. Using nautical miles for range would be mixing apples and oranges. I can't find a reference to nautical miles or knots in any Lockheed document published in the 1930s.
Ah yes, of course - MPH rather than knots would imply statute miles.
As you say, context is everything.
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Which is in common use today in air navigation?
I would think that, as airplanes were invented on land, aviators would tend to use statute miles. It's only when you start navigating over oceans, especially with navigators who have a maritime background, that it might occur to use nautical miles.
I think speculation on whether this (confusion over units of distance) was a factor in navigation or range calculation has already been covered and that it is not.
However, I had another thought about measurements of volume. AE would measure her fuel in US gallons, and range calculations would be based on those. However, she traversed, landed in, and refueled in places under British control or influence, where Imperial gallons (1/5 bigger) are used. Presumably this was not a source of confusion as to how much fuel she had?
My Morgan brochure from 1970 (the year of my car) gives fuel consumption figures I have never achieved -- then I realized they're in Imperial gallons!
Don
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However, I had another thought about measurements of volume. AE would measure her fuel in US gallons, and range calculations would be based on those. However, she traversed, landed in, and refueled in places under British control or influence, where Imperial gallons (1/5 bigger) are used. Presumably this was not a source of confusion as to how much fuel she had?
I don't know how closely she checked to make the gallons she ordered put in the airplane were US gallons, but it wouldn't have made much difference until she got to New Guinea and had the plane fueled for the Howland flight. None of the other world flight legs were anywhere near as long, so the fuel load she ordered was no more than was needed for the flight with an appropriate reserve. If somebody put in Imperial gallons by mistake, a little extra gas was no big deal.