Jet A Nominal Flammability Range

The flammable range of Jet A for tanks that were ~1/8 full of fuel and at uniform temperature was determined by Nestor in the 1960s.

Nestor, L. (1967). Investigation of turbine fuel flammability within aircraft fuel tanks. Final Report DS-67-7, Naval Air Propulsion Test Center, Naval Base, Philadelphia.

A simple representation of Nestor's experimental data is to fit the flammability limits to a straight line in altitude v. temperature coordinates using the properties of the standard atmosphere to convert from pressure to altitude. The results are shown in the plot.

Jet A flammability diagram

Numerical values for the flammability limits are given in the table below. Actual limits for an accident situation will depend on the amount of fuel, fuel flashpoint, weathering, temperature nonuniformity with the tank, and type of ignition source. See Exhibits 20D, 20L, and 20T in the Documents section for a detailed discussion of these issues.

Z P TLFL TUFL
(kft) (psia) (C) (F) (C) (F)
0 14.7 35.0 95.0 85.0 185.0
5 12.4 31.8 89.2 79.6 175.2
10 10.4 28.6 83.4 74.1 165.4
15 8.5 25.3 77.6 68.7 155.6
20 6.9 22.1 71.8 63.2 145.8
25 5.5 18.9 66.0 57.8 136.0
30 4.3 15.7 60.2 52.3 126.2
35 3.4 12.4 54.4 46.9 116.4
40 2.6 9.2 48.6 41.4 106.6

Last Updated on 5/31/02
By Joe Shepherd