Learjet 20 Series Pilot Training Manual page 108

ANTI-ICING ADDITIVE
Any approved fuels not containing the addi-
tive must have it blended during refueling.
Prior to refueling, check with the fuel supplier
to determine if the fuel contains anti-icing
additive meeting the requirements of MIL-I-
27686. The additive must be used in amounts
not to exceed 0.15% by volume and a minimum
concentration of 0.06%. Not less than 20 fluid
ounces (1 can) of additive per 260 gallons
(984.2 liters) of fuel nor more than 20 fluid
ounces per 104 gallons (393.7 liters) of fuel
should be used. Refer to Section II of the ap-
proved AFM for the proper anti-icing additive
blending procedure.
CAUTION
Lack of anti-icing additive may cause
fuel filter icing and subsequent en-
gine flameout.
REFUELING
Refueling is accomplished through the tip
tank filler caps (Figure 5-11). The fuel begins
to flow by gravity into the wing tanks as the
tip tanks reach one-half full. The wing standby
pumps are used to fill the fuselage tank. (See
Fuel Transfer System, this chapter.) A ground
power unit should be used, if possible, be-
cause of the requirement to operate the standby
pumps. Refer to the approved AFM for de-
tailed refueling procedures.
WARNING
Do not completely fill one tank be-
fore adding fuel to the opposite tank.
Fill both tanks simultaneously, or
alternately add 125 gallons (473.2
liters) of fuel to each tank until de-
sired amount is obtained. Failure to
follow this procedure will result in
excessive lateral unbalance.
LEARJET 20 SERIES PILOT TRAINING MANUAL
FOR TRAINING PURPOSES ONLY
CAUTION
On models 25C and D with the FUS
VALVE switch, do not set the FUS
VALVE switch to OPEN. Check to
assure that it is set to CLOSE.
Figure 5-11. Refueling Filler Cap
OPERATIONAL
CONSIDERATIONS
Maximum demonstrated fuel imbalance for
landing is 600 pounds in one tip tank.
Maximum tip tank fuel for landing is 800
pounds in each tip tank.
A minimum of 600 pounds of fuel in each
wing tank is required for takeoff and inten-
tional go-around.
FlightSafety
international
5-17