Fuels in Transportation - Decreasing Fuel Consumption and Exhaust Gas Emissions in Transportation - page 24

Table 2.10 Specifications for fuel to be used in aircraft turbine engines for emission testing
(Appendix 4 of ICAO Annex 16, Volume II)
Properties Unit Value

kg m 3 Density at 15C (59F) 780-820

Distillation temperature
10% boiling point C 155-201

(F) 311-394

Final boiling point C 235-285

(F) 455-545

MJ kg -1 Heating value of combustion 42.86-43.50

(BTU lb -1 ) (18.42-18.70) 9 10 3

Aromatics % vol 15-23

Naphthalene % vol 1.0-3.5

Smoke point mm

(in)

20-28
0.79-1.10

Hydrogen % mass 13.4-14.1

Sulfur % mass \0.3

m 2 s -1
ft 2 s -1

(2.5-6.5) 9 10 -6
(27.22-70.76) 9 10 -6

Kinematic viscosity at
-20C(-4F)

2.3.3 Alternative Fuels to Kerosene in Aviation

Airport infrastructure is optimized for supplying, delivering, and storing kerosene
fuels. Any significant changes in fuel type or specification require major modifi-
cations of all these elements. This is a serious matter involving major perturbations
to the existing system, with significant effort and costs.
Alternative fuels have a significantly lower energy density compared with ker-
osene. For this reason, airplanes with alternative fuels propulsed jet engines have to
be designed with larger fuel tanks. Table 2.11 compares the net heats in the
combustion processes of several alternative fuels based on weight and volume [ 37 ].
Alternative fuels include alcohols, methane and hydrogen, and methyl esters of
vegetable oils as extenders for kerosene. They must be compatible with kerosene
and must have sufficient energy density, meet payload and range requirements, and
must also be compatible with all metallic and non-metallic parts used in the fuel
systems of jet engines, and must achieve adequate lubrication to ensure current
safety standards.
The introduction of alternative fuels require new storage and supply systems for
current aircraft and airports. The limited availability of new fuels at several air-
ports also requires a new quality of service for aircraft diverted by weather or
mechanical problems.
Table 2.12 shows the most important properties of alternative fuels in aviation.
The military has pioneered the application of biogenic fuels. At first, the U.S.
Air Force introduced using biogenic fuels in 2011. The Federal Aviation
Administration (FAA) also wants to allow a 50% addition of biogenic fuel to