This may be the most esoteric question asked here in awhile.
Anyone familiar with French engines of the '20s and the oil they used?
Over on the UK Key Publishing (
FlyPast, The Aeroplane) forum, a TIGHAR-skeptic member posted about the groups search for
The White Bird flown by Frenchmen Charles Nungesser, and Francois Coli.
I'm sure most of you know the story, they disappeared during a flight from Paris to New Your, vying for the prize Charles Lindbergh would win two weeks later. There is no consensus on where they may have come down. Perhaps Newfoundland, perhaps Maine.
The post quotes the group as saying they have hopes that the piece of metal dragged out of a pond in Maine is from the aircraft.
So here us the Key Publishing poster quoting TIGHAR....
"When the artifact first emerged from the silt, the interior surface was caked with a black sooty substance that was greasy to the touch. Experiments have now shown that burned castor oil leaves a black sooty residue that is greasy to the touch. Burned petroleum-based oil does not. By the 1920s, American internal combustion engines were lubricated with petroleum oil. All of the aircraft lost while trying to fly the Atlantic in the 1920s were powered by American radial engines lubricated with petroleum oil – except L’Oiseau Blanc. In short, if the residue on the artifact was burned castor oil, the fabled Plane in the Pond could only be L’Oiseau Blanc. "
I'm not trying to restart discussion about the group and its various efforts.
One either likes them...or not....
My question is...
is the group correct about French engines being lubricated by Castor Oil as late as 1927?The engine in question is a liquid-cooled, normally-aspirated 24.429 liter (1,490.751-cubic-inch) Lorraine-Dietrich (W-12) (SOHC) engine with a compression ratio of 6:1 which produced 443.8 horsepower) at 1,850 r.p.m.
If they were, it seems odd since there were better lubricants available by then.
One related question, if an engine was designed to run on castor oil, could it be modified to use more modern motor oils?
While restored WWI rotary and radials may still use castor oil, I'd suggest those low power engines, flown for relatively short periods are entirely different that a 400+ hp engine flying for 30 hours.
One also wonders if testing the sooty residue would indicate whether it is castor oil based or petroleum based?.
Getting an answer now would prevent the group from barking up the wrong tree like they did with the aluminum patch they suspected (and tried very hard to prove) was from Earhart's Lockheed before finally admitting, only after after decades, it was from a C-47 as many always said it was (the metallurgy report indicated it was from WWII, not the late '30s).
So, any experts here on French engines or old oil?
Last edited by
JohnB on Sat May 24, 2025 7:51 pm, edited 1 time in total.