E-mail Address: GAVUFO@aol.com
The ongoing NTSB hearings per regards the TWA 800 explosion has
produced a contradiction between Commander Donaldson and a Boeing expert vis a
vis the ignition point of Jet A-1. Could you tell me who is correct?
I will call your attention to the flammability range (Percentage
By Volume) of Jet A-1 vapor contained at enclosure (1). (Pg. 71,
Table 8, Handbook of Aviation Fuels Properties, CRC Report 530,
1988) This table also depicts the minimum temperature (closed
cup flash point) where a flame introduced into the cup of heated
fuel will ignite the minuscule amount of vapor at the surface of
the fuel. Because C12H24 produces a very heavy vapor molecule,
at aircraft operation temperatures, if it exists at all, it stays
very close to the surface of the liquid fuel and does not mix
well with air. In other words the table tells us at 53 C or 127 F
just enough molecules of C12H24 are energized to break the
surface tension, leave the liquid and mix in a 6:994 ratio (.006
Vapor, .994 Air) with air in a thin layer just above the surface.
It also means this fuel is so safe a maintenance employee could
have taken a smoke break standing in the residual fuel of TWA's
tank, reached down and put out his lit match in the fuel without
consequence at temperatures up to and including 126 F!
According to the Boeing Fuel Tank Expert testimony this morning (12.9) the flash
temp of Jet A is 100 degrees and not 127 degrees.
Thanks for your time. Gavin.
Back to Hangar talk
NOTE: Reviews and Opinions do not necessarily represent those of Landings, its
personnel and employees.