TM 1-1510-223-10
Change 3 2-87
Table 2-11. Standard, Alternate, and Emergency Fuels
EMERGENCY FUEL
ENGINE
ARMY STANDARD FUEL
ALTERNATE TYPE
TYPE
*MAX HOURS
PT6A
MIL-T-83133
MIL-T-5624
MIL-G-5572
150
Grade JP-8
Grade JP-4/5
Any AV Gas
* Maximum operating hours with indicated fuel between engine overhauls (TBO).
Table 2-12. Recommended Fluid Dilution Chart
AMBIENT
TEMPERATURE
( F)
PERCENT
DEFROSTING
FLUID BY VOLUME
PERCENT WATER
BY
VOLUME
FREEZING POINT OF
MIXTURE ( F)
(APPROXIMATE)
30 and above
20
80
10
20
30
70
0
10
40
60
-15
0
45
55
-25
10
50
50
-35
-20
55
45
-45
-30
60
40
-55
1.
Use anti-icing and deicing fluid (MIL-A-8243 or commercial fluids).
2.
Heat Mixture to a temperature of 82 to 93 C (180 to 200 F).
2-93. FUEL TYPES.
a. Approved fuel types are as follows: Army Standard
Fuels. Army standard fuel is JP-8.
b. Alternate Fuels, Army Alternate fuels are JP-5 and
JP-8.
c. Emergency Fuel. Avgas is an emergency fuel and
subject to a 150 hour time limit.
2-94. USE OF FUELS.
Fuel is used as follows:
a. Fuel limitations. Fuel limitations are outlined in
Chapter 5. For the purpose of recording, fuel mixtures
shall be identified as to the major component of the mix-
ture, except when the mixture contains leaded gasoline.
The use of any fuels other than standard will be entered
in the FAULTS/REMARKS column of DA Form 2408-13,
Aircraft Maintenance and Inspection Record, noting the
type of fuel, additives, and duration of operation.
b. Use of Kerosene Fuels. The use of kerosene fuels
(JP-5 type) in turbine engines dictates the need for ob-
servance of special precautions. Both ground starts and
air restarts at low temperature may be more difficult due
to low vapor pressure. Kerosene fuels having a freezing
point of -40 C (-40 F), limit the maximum altitude of a
mission to 28,000 feet under standard day conditions.
c. Mixing of Fuels in Aircraft Tanks. When changing
from one type of authorized fuel to another, for example
JP-4 to JP-5, it is not necessary to drain the aircraft fuel
system before adding the new fuel.
d. Fuel Specifications. Fuels having the same NATO
code number are interchangeable. Jet fuels conforming
to ASTM D-1655 specification may be used when
MIL-T-5624 fuels are not available. This usually occurs
during cross-country flights where aircraft using NATO
F-44 (JP-5) are refueling with NATO F-40 (JP-4) or com-
mercial ASTM type B fuels. Whenever this condition oc-
curs, the engine operating characteristics may change in
that lower operating temperature, slower acceleration,
lower engine speed, easier starting, and shorter range
may be experienced. The reverse is true when changing
from F-40 (JP-4) fuel to F-44 (JP-5) or Commercial
ASTM Type A-1 fuels. Most commercial turbine engines
will operate satisfactorily on either kerosene or JP-4 type
fuel. The difference in specific gravity may possibly re-
quire fuel control adjustments; if so, the recommenda-
tions of the manufacturers of the engine and airframe are
to be followed.
2-95. SERVICING OIL SYSTEM.
Anintegraloiltankoccupiesthecavityformedbetween
the accessory gearbox housing and the compressor inlet
