Landing Gear Down Safety Lock Adjustment - Piper PA-24 Comanche Service Manual

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PIPER COMANCHE SERVICE MANUAL
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FIGURE 6-21. LANDING GEAR DOWN SAFETY LOCK INSTALLATION
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Adjustment Of Landing Gear Down Safety Lock. The purpose of the gear down safety lock is
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provide an additional means to retain the gear retraction torque tube assembly in the down position with the
gear transmission disengaged (emergency extension condition). Landing forces are absorbed by the over
center mechanism held in position by springs at each gear and are not intended to be transferred t o .
push-pull rod and cables.
a. Ascertain that the landing gear is properly adjusted.
b. Adjust the gear down safety lock by the following procedure:
I. Place the airplane on jacks. (Refer to Jacking. Section 11.)
2. Disconnect the retraction transmission by pulling up on the emergency release lever.
3. The down safety lock should be adjusted as close to the spacer (I) on the torque arm thru
bolt (2) as possible. yet freely engage when the gear is fully extended.
4. To adjust the lock. remove cotter pin (7). loosen jam nut (6) and turn lock arm (4) in the desired
direction.
5. If one-half turn is needed for correct adjustment. remove bolt (10) attaching lock fitting
(8)
to the bulkhead bracket and turn fitting in the desired direction.
6. Install fitting and spring (9) in the bulkhead bracket and secure with bolt.
7. Tighten jam nut. install cotter pin and safety wire attachment bolt head.
c. Check the gear down safety lock by using the following procedure:
1. Install the emergency gear extension lever in the torque tube socket. making sure it is properly
seated and fully extended.
2. Attach an accurate spring scale (0 to 100 pound range) to the bottom of the extension lever
knob.
3. Pull out the gear motor circuit breaker and turn on master switch.
4. Disengage the down safety lock and measure force on the extension lever by pulling
horizontally aft on the spring scales until the gear downlock light goes out.
5. Engage the down safety lock and make the same force measurement with the addition of 35
pounds to the first measurement.
6.
The gear downlock light should remain "ON."
7. If the gear downlock light goes out. check adjustment of the landing gear retraction system
per Paragraph 6-51.
ISSUED: 8/18/72
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LANDING GEAR AND BRAKE SYSTEM