The following information is derived from the FAAs Service Difficulty Reports and Aviation Maintenance Alerts. Click here to view “Airworthiness Directives.”
The FAA has approved Exxon Aviation Oil Elite 20W-50 for use in Lycoming O-320-H and O-360-E series engines as fulfilling the requirements of AD 80-04-03R2 – making it the third oil approved as an alternative method of compliance.
The AD was aimed at preventing excessive wear and oil contamination due to spalling of the hydraulic lifters. It requires operators to add a Lycoming-approved oil additive at each 50-hour oil change. In 1987, the FAA determined that Aeroshell Oil W 15W-50 contained the same anti-wear additive as the Lycoming additive and approved the use of Aeroshell as an alternative method of compliance. In 1999, Aeroshell W 100 Plus was added to the list. Earlier this year, the Exxon oil was determined to be comparable as well. The additives are intended to prevent excessive wear at engine start.
The approval does come with conditions. Using any of the three approved oils means that the operator must use the same brand and formula any time oil is added during the oil change interval. If it is unavailable, the operator can use up to two quarts of an alternative oil. If more than two quarts are necessary, then a can of the Lycoming additive must be added as well.In addition, the FAA has decided that if the oil change interval is extended beyond 50 hours for any reason, a can of the Lycoming additive must be used at 50 hours since the last oil change.
Beech A36 Bonanza
Improper Rudder Cable Routing
During the first annual inspection on a new aircraft, the inspector found a misrouted rudder cable.Evidently, during assembly, the manufacturer routed the rudder cable through the wrong bulkhead lightening hole in the area of the landing gear actuator. The cable did not yet display damage.Part total time – 69 hours.
Cessna 172M Skyhawk
Chafing Fuel Line
During an annual inspection, the maintenance technician discovered a fuel line chafing against the steering rod. The fuel line was located between the fuel selector valve and the fuel strainer and passed under the copilots rudder pedals. Each time the rudder pedals moved, the steering rod rubbed against the fuel line at a bend radius. The fuel line had worn to the point of imminent failure. When the technician installed a new fuel line, he discovered it also made contact with the steering rod during rudder pedal movement. He hand-formed the fuel line to provide adequate clearance.The operators fleet included four like aircraft and one other aircraft had this defect.Part total time – 2,428 hours.
Cessna R182 Skylane
Nose Gear Down-Lock Actuator
A technician complying with SB 95-20 to replace the downlock pins discovered they were defective and inspected the attaching components further. He discovered the nose gear drag link attachment bracket cracked through the upper rivet hole used to attach the bracket to the airframe. He also found several related cracks in the surrounding structure that the bracket hid from view. The grip length of the drag link attachment bolt displayed severe wear. Part total time – 3,935 hours.
Cessna T210N Centurion
Electrical System Failure
The pilot reported that when he tried to lower the landing gear the hydraulic pump began running and then stopped in midtravel. At the same time, the entire electrical system failed. The pilot lowered the landing gear using the emergency system and made a safe landing.The master switch solenoid had an open electromagnetic coil wire. The wire was broken and the terminal was severely corroded. Part total time – 5,658 hours.
Engine Exhaust System Defect
During several flights, the pilot noticed that the CO indicator in the cockpit turned black.A technician discovered a crack approximately 1.75-inches long in the engine at the base of the No. 2 cylinder exhaust pipe. He also discovered the exhaust system flanges, which mate to the No. 1 and No. 5 cylinders, were warped approximately .020 inch, the No. 4 cylinder exhaust flange was distorted, and the gasket was damaged and displaced. The SDR database contains two additional reports of similar failures. Preload stress may have been induced on the engine exhaust system members when they were initially installed. The stress culminated in the damage found.Part total time – 45 hours.
Piper PA-24-250 Comanche
Landing Gear Collapse
Following an accident involving landing gear collapse, an investigator found the links connecting the landing gear motor release arms to the motor release tube were bent.Both the left and right release arms were bent outboard, which resulted in restriction of the motor release tube travel. The bent arms made it impossible to re-engage the gear motor to the gear linkage mechanism. The pilot may have attempted to raise the gear with the motor disconnected, which caused the release tube to drop into a position where it interfered with the gear mechanism.Part total time – 4,595 hours.
Piper PA-28-181 Archer
Fuel Indicator Failure
The owner complained that the left fuel tank gauge indicated empty even when the tank was full.A maintenance technician found the float block detached from the fuel quantity sending unit float swing arm inside the tank. The float block was worn so severely that it slipped over the retaining washer on the swing arm.Part total time – 4,122 hours.
Piper PA-28R-200 Arrow
Aileron Bracket Crack
While conducting other maintenance, the technician discovered a crack in the left aileron bellcrank lower aileron support bracket.Approximately one year earlier, the submitter found the same defect on the right aileron control system. The crack allowed the support bracket to flex enough to produce several inches of play at the aileron surface. Part total time – 5,191 hours.
Piper PA-31-350 Chieftain
Main Landing Gear Failure
The right main landing gear failed to retract after takeoff. Attempts to lower the gear failed and the pilot landed with an unsafe right main gear indication. After the landing rollout, the right main gear collapsed.A technician found a broken right main gear actuator rod-end. Evidently, the rod-end failed just after unlocking the gear. This prevented the gear from going back into the down-and-locked position.Part total time – 11,364 hours.
Piper PA-34-200 Seneca
Nose Landing Gear Failure
During a landing approach, the pilot noticed an unsafe nose landing gear indication when he selected the gear to the down position. All attempts to attain a safe nose gear indication failed, and the nose landing gear collapsed upon landing. A technician found the nose gear roller had become dislodged from the track assembly. The failure may have been due to excessive play in the mounting hardware for the steering channel assembly, normal wear or ground handling damage to the assembly.Part total time – 7,460 hours.
Piper PA-34-200T Seneca II
Flight Control Cable Damage
During a scheduled inspection, the technician discovered a damaged stabilator trim tab control cable.At fuselage station 187.84 the cable passed through a bulkhead hole and chafed against the side of the hole. When the technician installed a new cable, he had to make adjustments to the pitch trim system to provide proper clearance for the cable to pass through the bulkhead.Part total time – 3,464 hours.
Piper PA-34-220T Seneca III
Fuel Servo Missing Seal
After replacing the fuel servo on the left engine, the technician conducted a pressure test. With pressure on the system, fuel leaked from the inlet port fitting.The technician removed the inlet fitting and found the O-ring seal was missing. The fuel servo had come from the manufacturer with all of the fittings installed and torqued. Part total time – 0 hours.
Teledyne Continental IO-520C
During a scheduled inspection of a Beech 58 Baron, the technician removed the No. 1 cylinder from the left engine and discovered a crack. The crack, located in the cylinder pad boss, traveled from the cylinder hold-down stud boss to the cylinder.The technician found the same defect on the No. 4 cylinder on the right engine. On the right engine, the crack relieved tension on the stud and allowed it to turn into the case and contact the connecting rod throw. The resulting force caused massive multiple fractures of the engine case. Engine time since overhaul – 1,333 hours.