Squawk Box

The following information is derived from the FAAs Service Difficulty Reports and Aviation Maintenance Alerts.

This VHF comm antenna was squawked for fluttering. Inspection revealed antenna was installed with no supporting doubler. Upon removal, a 5.5-inch radial crack was discovered around the antenna base, with a crack in an adjacent stringer. Skin under antenna also corroded due to no sealant being applied to base during installation.Part Total Time: Unknown

Failed Landing Gear MotorAfter takeoff, crew selected gear lever to up. Gear traveled halfway up and stopped. Crew selected holding area and ran checklist, manually lowering gear, followed by normal landing. Inspection revealed landing gear motor had failed and tripped the 60-amp circuit breaker under the floor. Motor was repaired and ops check was good.Part Total Time: 9452.0 hours

The left main gear downlock actuator failed while the airplane was airborne and the landing gear was in the up position. Since the lock collapsed into its locked position before the gear was down, the left main gear was out of sequence. The result was that the pilot followed the flight manual procedure of pumping the gear fully up and then making an emergency gear-up landing.Part total time: 3379 hours

Aircraft departed but pilot could not retract landing gear. Pilot diverted to nearby airport without problems. Maintenance found a broken wire at the gear selector switch. Repaired wire, ops checks good.Part Total Time: 15,557 hours

After only 26 hours of operation after new parts were installed, this magneto quit producing spark. Troubleshooting found the point timing had drifted off and was impossible to reset within manual limits. The plastic cam follower was found worn or melted. New parts were installed and functionally checked good. Engine is a Continental IO-360-A, installed in a Maule M-4-210Part Total Time: 26.0 hours

Before the second landing, the crew selected gear down, which showed down and locked, but the crew saw and smelled smoke. The landing gear circuit breaker tripped after gear completed cycle. Inspection confirmed source of smoke was from the landing gear actuator motor and a faulty dynamic brake relay (mfr p/n SM50D7) is suspected to have caused the landing gear motor to overtravel against hard stop and smoke.

The aircraft was descending when the pilot heard a loud “pop” from the copilot windshield (p/n 10138402522), which visual inspection revealed had cracked and shattered. Pilot requested “priority handling” and was informed he would be #6 for the runway. Due to factors such as night flight, unknown damage to copilot windshield and poor weather, the pilot declared an emergency and again requested priority handling, followed by an uneventful landing. Post-flight inspection revealed no obvious signs of foreign impact.

The pilot observed smoke in the cockpit, declared an emergency and landed normally. On inspection, the muffler’s aft wall was missing and exhaust was directed onto the battery box, which melted the battery and battery contactor, clock fuse holder, both battery cables and boots. Also, the gascolator push/pull control knob was melted and all wiring into the engine compartment was destroyed. The owner recalls the engine backfiring when a student performed ignition test at high rpm.

Nose strut debonded at nose fork bearing spindle. Spindle and strut are bonded via a hot-bond agent while in autoclave. Suspect debonding occurred due to unreported hard landings and extreme stress due to improper ground handling.