preload is maintained with jacking of aircraft by
and signs posted stating "DANGER: AIRCRAFT ON
rotation of the chain tensioning grip.
JACKS." The area below and around the aircraft must
be cleared of all equipment not required for the jacking
operation. Install jack adapters, aircraft mooring
adapters, and tie-down chains as required by the MIM.
Figure 1-31 shows an example of carrier tie-down
Use extreme care to raise wing jacks in
for aircraft jacking. Position and extend wing and
coordinated, small, equal amounts. Preload on the
nose jacks until seated on wing jack and tie-down
tie-down chain is too high when tensioning grip
cannot be rotated manually.
NOTE: Some aircraft require the extension of the
center screw to provide for clearance of the gear doors.
Screw the lock collar down as each jack is being
extended. Jack the aircraft until its wheels clear the
deck, and set the lock collar handtight. Set each
tie-down chain to preload by manually rotating and
Apply jack pressure on each jack without lifting the
tightening tensioning grip.
aircraft, and check to see that the base of each jack is
evenly seated. Correct base position of jack, as
required, for firm base seating. For shipboard
operations, all jacks must be tie-down before jacking
An aircraft leveling technique is shown in figure
aircraft with a minimum of three tie-down chains per
1-32. Jack aircraft at wing and nose jack point as
jack. The jack must be tied down at the spring-loaded
described earlier. Attach plumb bob and string to eye
wheel caster mounts, thus allowing the jacks to make
bolt at FS 259 (fuselage station). Position the plumb
small movements with the aircraft jack points. Release
bob directly over the leveling plate on floor of aircraft.
the aircraft parking brake. Remove main landing gear
Level aircraft laterally (left to right) by adjusting wing
chocks. Jack aircraft evenly and extend tie-down chains
jacks until plumb bob tip is directly above the center
while jacking. Extension of tie-down chains must be
line in the leveling plate. Level the aircraft
coordinated in a way that preload on each tie-down
longitudinally (forward and aft) by adjusting the nose
chain is partially removed before jacking. Partial
jack until plumb bob tip is directly above FS 259 line on
Figure 1-31.--Carrier tie-downs for aircraft jacking.