3-30-9 When You Use the Equipment for Emergency Axle Jacks
1.
When you have a flat tire on the NLG or the MLG, special equipment can be necessary. The ground clearance can be too small to permit you to use the usual axle jacks. See Figure 3-45 for details on the jack equipment for this condition.
2.
Before you use the jacks, make sure that you install the locks (downlock pins) in the landing gears. See SUBJECT 4-00-1 of this document and MM 32-00-30 for procedures and more information on downlock pin installation. Use the applicable procedures from the maintenance manuals to lift the gears to the usual jack height. This height permits you to use a jack between the gear jack point and the ground. Install the usual gear axle jack. Lift the gear with the usual gear axle jack to a height that permits you to replace a wheel.
3-30-9
WHEN YOU USE THE EQUIPMENT FOR EMERGENCY AXLE JACKS Page 3-87 Jul 01/2005
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3-30-10 When You Lift the Airplane with Pneumatic Bags
1. We recommend this type of a pneumatic bag:
A. High stability (with internal drop threads).
B. Multiple-element.
C. Small capacity, 25 ton (22 metric ton).
D. Large capacity, 40 ton (36 metric ton).
CAUTION: YOU MUST KNOW HOW THE BAGS OPERATE. MAKE SURE THAT YOU KNOW THE CAPACITY OF THE BAG AND THE MAXIMUM PERMITTED BAG PRESSURE ON THE AIRPLANE. THERE IS A DIFFERENCE.
2.
Usual bags of the small capacity are shown in Figure 3-47. Usual bags of the large capacity are shown in Figure 3-48. These figures show the bag pressure (inflation pressure). These figures also show the capacity that is available when you lift the airplane at that pressure. See Figure 3-49 for bag locations and limits (allowable surface bearing loads).
3.
The manufacturers make the bags as stable as possible. This does not prevent large horizontal forces in all bag procedures. These forces make a condition that is not stable. Do not use the bags when the speed of the wind is more than 23 mph, 20 knots or 37 km/hour. Make sure that you use a tether system (see SECTION 3-20).
4.
Lift the airplane from the lowest point first. Make sure that the airplane gets to a level attitude. Make sure that the airplane also stays as level as possible while you lift it. Attach a tool (plumb bob) to the nose or to the lower fuselage. This tool helps you to monitor the position of the airplane. This tool also helps you keep the horizontal forces (side loads) on the bags to a minimum.
5.
Put the bags in positions that permit the center of their total force to align with the airplane CG. Install the bags very carefully. This prevents more damage to the airplane. The areas for the bag locations along the fuselage and wings are shown in Figure 3-49.
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