WARNING: BE CAREFUL IN HIGH WINDS. DO NOT USE JACKS TO LIFT THE AIRPLANE IN VERY HIGH WINDS (MORE THAN 40 MPH, 35 KNOTS OR 64 KM/HOUR).
WARNING: USE CAUTION WHILE YOU LIFT THE AIRPLANE. A STRUCTURE THAT IS DAMAGED (DEFORMED AND PRELOADED) CAN SUDDENLY MOVE AT HIGH SPEED.
A. You can lift the airplane with recovery jacks (low profile) or pneumatic bags (25 to 40 ton or 23 to 36 metric ton multi-cell). You can use a system of jacks, bags and fuselage slings. You can also use a system of jacks and fuselage slings. See Figure 3-49 for bag locations and limits (allowable surface bearing loads).
B. When you lift the airplane, keep it in a level attitude. This will make sure that the airplane CG stays in the correct range. The procedure that you use to lift the airplane makes no difference.
C. Make sure the CG is in the correct position. If you use jacks, calculate the forces on the jack points. Make sure you keep these same forces while you lift the airplane. This will prevent a dangerous movement of the airplane.
D. If you can do it, remove all possible weight from the airplane. This will permit you to lift the airplane with an easier and a safer procedure. It is possible to lift the airplane with the fuel on it. When you lift a wing, it can be good to move the fuel to the opposite wing. To correct the CG of the airplane, you can add some ballast. You can put the ballast in the forward cargo compartment or the aft cargo compartment.
E. Lift the airplane with a procedure that prevents large horizontal forces at the jack points. The procedure must also prevent large forces that can cause movement of the pneumatic bags. Use tools (levels and plumb bobs) to move the airplane to the correct attitude (horizontal and vertical) when you lift the airplane. Use these tools to make sure the airplane keeps the correct attitude while you continue to lift the airplane.
F. If the airplane is on soft (or muddy) ground, it can be best to use pneumatic bags. If the airplane is on hard ground, it can be best to use movable cranes. If you have cranes of the correct capacity, you can quickly move (or walk) the airplane. It is possible that you can move it the full distance to a runway or a repair area.
G. You must remove all possible fuel to decrease the airplane weight and to reduce the risk of a fuel fire.
3-30-1
GENERAL
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3-30-2 When You Prepare to Lift the Airplane
1.
Examine the recovery procedure. Look at the terrain and examine the airplane structures that are scheduled for the procedure. Make sure the airplane structural points are sufficient for the procedure. Damaged airplane structures and unsatisfactory ground conditions can change the procedures you use to lift the airplane.
2.
Install pins (downlock pins) on all the gears (in the extended position) immediately. This is a mandatory safety precaution.
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