Table 2-3. Fuels, Lubricants, Specifications, and Capacities
373.6 U.S. Gals.
MIL-L-7808 (See Notes 1, 3, and 4)
14 U.S. Quads
MIL-L-23699 (See Notes 2 and 3)
Hydraulic brake system
1 U.S. Pint
203 Cubic feet
MIL-L-7808 oil used in the engine oil system is specified for operation in ambient
temperatures below -40C (-40F). This oil may also be used when MIL-L-23699 oil is not
Under no circumstances shall MIL-L-23699 oil be used at ambient temperatures
below -40C (-40F). MIL-L-23699 oil used in engine oil system is authorized and
directed for use in ambient temperatures above -40C (-40F).
Do not mix MIL-L-23699 oil with MIL-L-7808 oil except in case of emergency. If it
becomes necessary to mix the oils, the applicable system shall be flushed within
six hours and filled with the proper oil.
Lubrication oil made to MIL-L-7808 by Shell Oil Company under their part number
307, qualification number 7D-1 shall NOT be used in U-21 series engines.
2. Refuel aircraft as soon as possible after
4. Carefully remove snow, water, and ice
from the aircraft fuel filler cap area before removing the
fuel filler cap. Remove only one aircraft tank filler cap at
3. Keep fuel servicing nozzles free of snow,
any one time, and replace each one immediately after
water, and mud at all times.
the servicing operation is completed.
5. Wipe all frost from fuel filler necks before
6. Drain water from fuel tanks, filter cases,
Prior to opening the fuel tank filler,
and pumps at least 30 minutes after each servicing, at
the hose nozzle static ground wire
least 30 minutes after each removal from heated shelter,
must be attached to the grounding
and before each flight. Preheat, when required, to
lugs that are located adjacent to filler