SDRs and Mx Alerts

Piper PA32: Aircraft landed safely, while taxiing, left tire went flat. Once the wheel fairing was removed, noted inboard wheel half was rubbing brakes. Pilot reported briefly smelling rubber after landing. Once disassembled, with brake disc removed, IB wheel half cracked along bead area, three inches and rim bowed out. Pilot reported wheel replaced six months earlier. Better inspection of wheels at time of tire change could have prevented this situation, according to submitter.

Mooney M20J: Optional vertically adjusting pilots seat moved aft during takeoff, found left rear bellcrank assembly cracked which distorted seat allowing seat pins not to fully engage seat tracks. Installed a new bellcrank and tube. New bellcrank had reinforcement straps welded at failure point. Seat operated normally after replacement.

Cessna P210N: Turbocharger misinstalled. Received turbo charger check valve and installed in correct orientation. Ran turbo charger and charger cavitated due to loss of oil supply. Further investigation revealed the new check valve was backwards internally, i. e. the check valve was at the opposite end of the fitting and flow arrow compared to the original check valve. Recommend that all check valves be examined to verify proper physical flow direction and properties.

Cessna 177A: During an annual inspection, right wing inboard L/E skin was found corroded through beneath stringer. A possible cause for the excessive corrosion may be water seeping through the air inlet hose installed above the affected area. This water enters through the L/E air inlet and creates rust in the steel wire wound hose and drips rust contaminated water on the wing surface below, which may accelerate the corrosion process. It is recommended that close attention be paid to that part of the wing and to that part of the wing and to the condition of the vent hose directly above it especially in aircraft that are stored outdoors. Applying corrosion resistant chemical to inside of wing would help situation.

Mitsubishi MU2B60: In flight, pilot noticed fluctuating oil pressure and torque. Precautionary landing made. Following troubleshooting, engine was disassembled and gearbox scavenge oil pump found to be cracked. Approximately 7 hours prior, the number 8 stainless oil scavenge line was found cracked. It is believed oil pressure cycling from line failure fractured scavenge pump. Replaced pump.

Falcon 50: Engine shut down at FL360, on departure. Flight crew and passengers heard loud bang and felt vibration. Flight crew observed number 3 engine N1 spooldown and 25 degree higher than normal ITT, engine oil pressure was normal. Engine was shut down and flight returned to departure airport. Postflight inspection of number 3 engine revealed debris in exhaust duct. No visible damage to the low pressure turbine, aft of fan or compressor area, forward. Suspect component failure forward of low pressure turbine. Engine removed for repair, shipped to manufacturer. Inspection teardown report pending. Uncertain what component in engine failed.

Lear 45: After takeoff, throttle would not come back. Throttle had to be forcibly pulled back out of takeoff setting. Cable was found bad.

Sikorsky S64F: The main rotor head sleeve and spindle assembly developed an oil leak while on aircraft and was noted during routine inspection. Upon removal and replacement with a serviceable assembly, a crack was found on the inner race of removed part. Visual inspection shows wear and corrosion typical for this part that has been in service. No other abnormalities with the exception of the crack. Crack is approximately three inches in length and runs in axial direction. This is the first time occurrence. Cause is unknown and no recommendations to prevent recurrence at this time.

Douglas DC10: Nose cowl was sent to submitter for repair. During evaluation, severe intergranular corrosion was discovered on the outer skin of the acoustic barrel. Suspect improper heat treatment at manufacture. Part is considered beyond economical repair and will be scrapped at submitters location.

Bell 407: Found max position of throttle (power lever angle) could not be obtained using normal adjustment procedure. Found copilot throttle linkage was fouling on collect elbow (PN 206-001-203-101). Linkage is attached to collective throttle lever with (NAS6603-9D) bolt installed with head facing forward. Due to installation of air communication bleed air heater kit (PN 407H-200M12 STC:SR00221DE) bolt had been turned around with head facing aft. Instructions call to replace factory bolt (NAS6603-9D) with shorter bolt (NAS6603-8D), not installed on this aircraft. Found that bolt (NAS6603-8D) also fouls if washer/cotter pin are installed incorrectly. Only in flight FADEC failure would pilot move throttle past (flight) detent position, using max throttle range. Aircraft to be checked for compliance.