JET FUEL
• Maximum altitude with a HOT FUEL
light on is 25,000 feet on airplanes with
a fuel temperature warning system.
• Maximum time with a low FUEL PRESS
light on is 10 hours between overhauls.
• On SNs 23-070 through 23-099, do not
transfer or crossflow fuel if below 5,000
feet and engine rpm is above 95%.
With the LOW FUEL warning light illumi-
nated, limit pitch attitude to the minimum
required for go-around.
Maximum fuel in tip to begin transfer is 760
pounds for model 25, and 800 pounds for mod-
els 23, 24, and 24B.
With wing jet pumps (main fuel boost pumps
on model 23) and standby pumps inoperative,
the engine-driven fuel pumps suction-feed
sufficient fuel to supply the engines at altitudes
of 25,000 feet or below.
Do not energize fuselage transfer system when
wing and tip tank are full.
Do not crossflow with wing jet pump inoperative.
Do not transfer fuel if crossflow valve fails to
open.
Maximum tip tank fuel for landing is 800
pounds in each tip for models 24, 24B, and 25,
and 640 pounds for model 23.
A minimum of 600 pounds of fuel in each
wing tank is required for takeoff and inten-
tional go-around.
If either wing tank is below 600 pounds, limit
prolonged pitch attitude to 10° noseup.
Minimum fuel temperature for takeoff is:
• Jet B/JP-4 .................... –54°C (–65° F)
• Jet A/Jet A-1 ............... –29°C (–20° F)
• AVGAS ........................ –54°C (–65° F)
5A-17
FOR TRAINING PURPOSES ONLY
LEARJET 20 SERIES PILOT TRAINING MANUAL
FlightSafety
international
Figure 5A-12. Refueling Filler Cap