SECTION III. FUEL/OIL
6-3-1. Fuel and Oil Data.
The CH 47D is equipped with six fuel tanks and an inte-
gral oil tank on each engine. The capacities of each fuel
tank and each oil tank are given in Chapter 2.
6-3-2. Fuel Weight and Moment.
Fuel moments for the forward auxiliary, main and aft
auxiliary fuel tanks are shown in figure 6-3-1. The fuel
arms for these tanks are constant thus, for a given weight
of fuel there is no variation in fuel moment with change
in fuel specific weight. The common auxiliary fuel tank
arm is 314.
The full tank usable fuel weight will vary depending upon
fuel specific weight. The gallon scales on figure 6-3-1 are
based on JP-4 @ 6.5 lb/gal, JP-5 @ 6.8lb/gal, and JP-8
@ 6.7 lb/gal. The aircraft fuel gage system was designed
for use with JP-4, but does tend to compensate for other
fuels and provide acceptable readings. When possible
the weight of fuel onboard should be determined by direct
reference to the aircraft fuel gages.
The following information is provided to show the general
range of fuel specific weights to be expected. Specific
weight of fuel will vary depending on fuel temperature.
Specific weight will decrease as fuel temperature rises
and increase as fuel temperature decreases at the rate
of approximately 0.1 lb/gal for each 15ºC change. Specif-
ic weight may also vary between lots of the same type
fuel at the same temperature by as much as 0.5 lb/gal.
The following approximate fuel specific weights at 15ºC
may be used for most mission planning.
6-3-3. Oil Data
For weight and balance purposes, the weight of engine
oil is included in the basic weight.