IAD02FA091

The airplane was in cruise flight at 3,500 feet mean sea level when the engine lost power. The pilot then performed a forced landing to trees. Examination of the Lycoming IO-540 series engine revealed that the zinc-plated crankshaft gear attachment bolt was fractured, and that the crankshaft no longer drove the gear. Fracture surface analysis revealed intergranular separation due to hydrogen-assisted cracking. Engines had previously been built with cadmium-plated bolts, but zinc-plated bolts were being used because they were readily available, and had a "positive impact" on production. Lycoming received 8,500 zinc-plated bolts between November 1996 and July 1998. Lycoming manufactured or re-built/overhauled 1,088 engines with zinc-plated bolts, and shipped 2,667 zinc-plated bolts as spares. Two zinc-plated gear bolt failures were documented in helicopter engines in 1998, due to hydrogen embrittlement. One bolt failed at 30 hours of operation, and the other at 19 hours. Lycoming and FAA personnel believed the failures occurred due to the higher loads generated by helicopters. Based upon the two failures, Lycoming removed the bolts from its stock as a "precautionary measure" in July 1998. Bolt recalls were issued by the helicopter manufacturer and Lycoming in July 1998. The FAA issued an Airworthiness Directive (AD) in February 1999 to replace the crankshaft bolts in affected helicopter engines worldwide. In July 1999, a Piper PA-32R-301 bolt failed due to hydrogen embrittlement at 327 hours. Between March 2000 and January 2001, two bolts failed on Royal Jordanian Falcon trainer airplanes, at 292 and 179 hours. As a "precautionary measure," Lycoming replaced the crankshaft gear bolts in the five-airplane Jordanian Falcon fleet about February 2001. Lycoming and FAA personnel believed the failures did not extend beyond helicopter and aerobatic applications, although the PA-32R-301 failure occurred in 1999. In June 2002, another bolt failed on a Piper PA-32R-301, at 448 hours. The engine was examined by Lycoming and FAA personnel, and a Lycoming laboratory report stated the failure was due to hydrogen embrittlement. In September 2002, this accident occurred, and as a result of the investigation, about 2 weeks after the accident, Lycoming issued a Service Bulletin (SB) to replace bolts on certain 540-series engines. In October 2002, the FAA issued an Emergency AD to also replace the bolts. The common cause for hydrogen embrittlement is a missed or under baked condition.

History of flight

On September 8, 2002, at 1821 eastern daylight time, a Piper PA 32R-301T, Canadian registration C-GKLY, was destroyed during a forced landing to wooded terrain in Byram Township, New Jersey. The certificated private pilot and one passenger were fatally injured, and two passengers were seriously injured. Visual meteorological conditions prevailed for the personal flight that originated at Teterboro Airport (TEB), Teterboro, New Jersey, at 1809. A visual flight rules flight plan was filed for the flight destined for London, Ontario, Canada, and conducted under 14 CFR Part 91.

Federal Aviation Administration (FAA) transcripts of air traffic control communications revealed that the pilot declared an emergency at 1817. The airplane was in cruise flight at 3,500 feet mean sea level (msl) when the pilot reported a loss of engine oil pressure. The pilot stated that he would attempt to reach Aeroflex-Andover Airport (12N), Andover, New Jersey. The controller advised the pilot that he was 6 miles from the airport and provided a heading and runway information.

Two witnesses near the accident site reported that the airplane maneuvered across their neighborhood, just above the trees, as it descended in a level attitude. The airplane then banked slightly to its left and descended into the trees.

One witness stated that the engine was sputtering. The second witness stated that he didn't recall hearing the engine, nor did he recall hearing anything unusual.

The accident occurred during daylight hours, in the vicinity of 40 degrees, 59.8 minutes north latitude, 74 degrees, 40.5 minutes west longitude.

Personnel information

The pilot held a Transport Canada private pilot license, issued August 21, 1997, and valid for aeroplanes, non-high performance, single engine land. A night endorsement was added to his license January 12, 1998. The pilot's logbook was recovered, but his total flight experience could not be determined. The logbook was designated Logbook #1 on July 1, 1996. The logbook entries annotated his initial flight training, and a total of 165.6 hours of flight experience up to November 28, 1997, the date of the last entry. In November 2001, the pilot reported 900 hours of flight experience to his insurance company.

The pilot's medical certificate was issued on October 30, 1998, with a requirement that he wear glasses. The pilot declared 375 hours of flight experience on that date. According to an air safety investigator with the Transportation Safety Board of Canada, the pilot's medical certificate was valid for 60 months from the date of issue in Canada, and valid for 24 months outside Canada.

Aircraft information

The airplane was a 1997 Piper PA 32R-301T. A review of the airplane's "journey log" revealed the most recent annual inspection was completed February 21, 2002, at 415.6 aircraft hours. The airplane's technical logs were not recovered.

According to Lycoming records, the airplane's engine, a TIO-540-AH1A, was built with a zinc-plated crankshaft gear bolt, part number STD-2209. The engine, which was manufactured on September 27, 1997, had accrued 488.8 hours since new.

Meteorological information

The weather, reported at an airport 16 miles southeast of Byram Township, included clear skies, with winds from 200 degrees at 5 knots.

Medical and pathological information

An autopsy was performed on the pilot by the Sussex County Medical Examiner, Newton, New Jersey. Toxicological testing was performed at the FAA Toxicology and Accident Research Laboratory, Oklahoma City, Oklahoma.

Wreckage and impact information

The wreckage was located in a residential neighborhood, about 3 miles east of Aeroflex Airport. It was examined on September 9, 2002, and all major components were accounted for at the scene. The airplane came to rest inverted, and wedged between two trees and a storage shed. Rescue workers had used logs and lumber to prop the fuselage onto its left side.

The wreckage path headed about 245 degrees magnetic, and was 110 feet in length. The initial impact point was in a tree about 80 feet above the ground. The left wing tip was at the base of the tree below the initial impact point. Trees along the wreckage path were broken off progressively closer to the ground in the direction of the main wreckage.

An examination of the wreckage revealed that the roof was crushed by impact, and that rescue personnel had cut the windshield posts. The empennage and tail section were separated aft of the cabin area, but remained attached by wires and cables. The vertical stabilizer, horizontal stabilator, and rudder were damaged, and wrapped around a tree where the airplane had come to rest.

Both wings were separated at the fuselage attach point, and the left wing had been consumed by fire. The inboard section of the right wing, with the right main landing gear attached, was connected to the right side of the fuselage by an aileron cable and a hydraulic line. The outboard section of the right wing was entangled with the left wing, and had also been consumed by fire.

Aileron cable continuity could not be established due to breaks in both aileron cables and the aileron balance cable. All cable breaks were 'broomstrawed'. Each aileron bellcrank had its respective aileron and balance cable ends still attached, and both aileron cable ends were still attached at the sprocket and chain assembly.

Rudder cable continuity was established from the cockpit to the rudder. Continuity could not be established to the stabilator due to breaks in the cables. However, the cables were traced from the flight controls, to the individual breaks, then back to the stabilator. All of those cable breaks were also 'broomstrawed'.

The interior of the airplane was damaged by fire. The throttle, propeller, and mixture levers were all in the full-forward position. All engine instruments indicated 'zero'.

Of the three propeller blades, one had no damage, one had little leading edge damage but was bent back about 45 degrees, and one had little leading edge damage but was curled back about 90 degrees. The propeller and crankshaft were subsequently rotated by hand.

The engine's top spark plugs were removed, and piston movement was noted in all cylinders as the crankshaft was rotated. However, no movement of engine accessories was noted. The rocker arm covers were removed, and no rocker arm movement occurred during crankshaft rotation.

The engine-driven fuel pump drive cover was removed, and the accessory section was rotated through the drive. The vacuum pump rotated, the magneto impulse couplings "snapped," and rocker arm movement was noted on all cylinders. However, during rotation of the accessory section and the valve train, the crankshaft did not turn.

The examination of the engine was suspended, and the engine was shipped to Textron Lycoming, Williamsport, Pennsylvania, for disassembly and further examination.

Tests and research

- Engine Examination -

On September 17, 2002, the engine examination was resumed at the factory under Safety Board supervision.

The examination revealed that the zinc-plated crankshaft gear attachment bolt was fractured, and that the crankshaft no longer drove the gear. An initial review of the manufacturer's specifications revealed that a cadmium-plated bolt was indicated for the crankshaft gear application.

A Scanning Electronic Microscope (SEM) examination of the fracture surfaces on the zinc-plated bolt revealed "intergranular separation due to hydrogen-assisted cracking."

- Additional Research/Documentation -

The following is a compilation of Lycoming letters, additional reference materials, FAA briefing materials from a meeting held on June 18, 2003, at Safety Board headquarters, and a combined FAA/Lycoming factual review letter, dated February 15, 2005. In order to provide historical