The main gear and gear support beam attached to the airplane wing structure at critical points by fuse pins. These fuse pins shear under extreme loads and provide a release of the gear to prevent major damage to the wing structure and prevent rupturing of the fuel tanks.
There are three gear fuse pins which break to let the gear structure come apart. The first is the pin which connects the drag strut to the trunnion link. The second is the pin which connects the upper downlock link to the upper spindle. The third is a torsional fuse which connects the lower side strut to the shock strut.
Six other fuse pins connect the gear to the wing structure. one fuse pin attaches the trunnion link into the forward trunnion bearing. Four fuse pins attach the aft trunnion bearing housing to the main landing gear support beam. One more fuse pins attaches the reactions link to the forward trunnion bearing housing at the outboard end of the link.
The main landing gear support beam is attached to the wing structure at the outboard end by another fuse pin.
9. If the landing gear is damaged, the repair can be as easy as a component replacement. A new landing gear can also be necessary. You must complete all repairs for the landing gear before you apply the airplane loads. Do not tow or winch the airplane before the gear repairs are completed.
NOTE: EXAMINE THE NOSE AND MAIN LANDING GEARS FOR A HARD LANDING (SEE THE MAINTENANCE MANUAL FOR PROCEDURES).
10. It can be possible that the airplane is too badly damaged to make a full recovery. You must make a decision about which of the components you can possibly keep. If you keep some components, you must do a different type of an operation (salvage operation). The procedures for that type of an operation are not included in this document.
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AIRPLANE RECOVERY DOCUMENT
Figure 2-2 MAIN LANDING GEAR COMPONENTS
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AIRPLANE DAMAGE ANALYSIS
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AIRPLANE RECOVERY DOCUMENT
Figure 2-3 MAIN LANDING GEAR FUSE PIN LOCATIONS
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2-10-2 Effect of Terrain and Weather
1.
Weather and terrain conditions are important. These conditions (plus any structural damage) help you in your selection of procedures to move the airplane.
2.
Look at the terrain near the airplane. The surface of the ground must be almost level. This level surface becomes a temporary road to move the airplane. You must make (or grade) the road if it is necessary (see Section SUBJECT 2-10-4).
3.
Weather conditions can cause problems for the recovery. In high winds, you must attach the airplane to the ground with tethers. In some locations, you must use irrigation pumps or drainage ditches to remove unwanted water.
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