SEA99FA113

While en route during an unknown phase of operation, the O-360-A1A engine, which had been overhauled by a facility in Canada and converted with 'high compression' pistons/cylinders, developed a partial power loss after about 35 hours of total operation. Metallurgical examination revealed that the #2 connecting rod fractured in two places due to fatigue at the rod end resulting in release of the rod from the crankshaft. No evidence of engine disassembly or maintenance by the owner/builder was found. Post-crash examination revealed holes in the upper engine case and disintegration of the #1 piston. A witness reported observing the aircraft at low altitude over gently rolling terrain trailing black smoke during which the pilot was observed to exit the aircraft. The aircraft rolled into a descending right turn and impacted the terrain 600 feet from the pilot's ground impact, and a post-crash explosion and fired ensued. Reconstruction of portions of the aircraft revealed sooting and evidence of pre-impact fire forward of the firewall in the vicinity of the gascolator as well as pre-impact heat damage to the Plexiglas windscreen and canopy. The only evidence of heat/fire distress observed during post-mortem was the pilot's eyebrows and forward hairline. The aircraft's canopy is airfoil shaped and during flight conditions would tend to create an aerodynamic low pressure condition near the top of the canopy. If the canopy were opened in flight with fire conditions existing along its forward exterior surface, the entrainment of hot air and fire within the upper cockpit interior environment may have become intolerable for the pilot.

History of flight

On July 10, 1999, approximately 1520 Pacific daylight time, an Alexander Van's model RV-8 homebuilt aircraft, N41VA, constructed by/registered to and being flown by a private pilot, was destroyed when it collided with terrain during an uncontrolled descent preceded by an in-flight fire during descent one nautical mile north of Lafayette, Oregon. The pilot was fatally injured. Visual meteorological conditions existed and no flight plan had been activated. The flight, which was personal, was to have been operated under 14CFR91, and originated from Arlington, Washington, earlier on the date of the accident. A fuel stop had been made at Scappoose, Oregon, between 1345-1445 hours.

An eyewitness located within about one-half mile of the crash site reported that he "heard the airplane revving its engine full force..." and "looked up to see the airplane flying level from west to east...." He further reported that the "airplane then started to nose down until it was going nearly strate [sic] down..." and that "the engine was revving full force untill [sic] it crashed and exploded..." (refer to attached witness statement). The witness, who was south of the aircraft's flight path and crash site, estimated the altitude of the aircraft as about 200 feet.

An ear witness located within one mile of the crash site reported hearing "a single engine plane engine go to a wide open throttle position for appox [sic] 2 or 4 sec[onds] and then nothing." He did not see the aircraft until after it impacted the terrain (refer to attached witness statement).

A third witness, who did not provide a written statement, was interviewed by both the investigator-in-charge and local law enforcement authorities. The interview with the Yamhill County Sheriff's Deputy (case number 99-002440) provided the following information: The witness "advised that he was in the field swathing when he saw and [sic] plane coming over the hill to the east very low and that it appeared to be on fire as there was lots of smoke coming from it. He said that it passed over the far end of the field and was about 200-300 feet high when he saw a person jump from the plane landing in the field where he had been cutting gras [sic] for seed. He said that the person striking the ground appeared to bounce about 3-4 feet into the air, the plane then went into a slight turn, banked sharply nosing over striking the ground in the uncut grass bursting into flame." The interview with the investigator-in-charge provided the following additional information: The witness reported hearing the aircraft's engine and described it as "smooth but high power" and that the aircraft was flying from west to east. He also reported that the interval between the time the pilot left the aircraft and impacted the ground was about three seconds and that the aircraft impacted the ground immediately after the pilot. He described the smoke as "black" and estimated the aircraft's altitude as 200 to 400 feet above ground.

Personnel information

A pilot logbook was acquired containing the pilot's name. The logbook was opened on July 29, 1977, and the final entry was observed to be dated March 22, 1999. Three flights in the RV-8 aircraft, all in N41VA, were observed entered in the logbook. These three flights (the last three entries in the log) were dated March 7th, 8th and 22nd consecutively, and totaled 6.0 hours. A tally of flight time within the log indicated that the pilot had logged 633 hours of total flight time of which 596 hours were pilot-in-command. The logbook also showed that the pilot had logged 82 flight hours in the RV-4 aircraft between March 30, 1997, and July 10, 1998, at which time the log indicated the RV-4 was sold.

The pilot's last medical examination, conducted February 25, 1999, was for a third class medical certificate and contained a special restriction and waiver. According to records maintained by the Federal Aviation Administration (FAA) the restriction stipulated that the pilot "must use hearing amplification."

Aircraft information

A License Agreement between the pilot/builder and Van's Aircraft, Inc., found with the aircraft records, indicated that the RV-8 kit was first purchased on November 20, 1997, and issued serial number 80544 by the kit producer.

The airframe logbook showed a date of manufacture of February 1, 1999, and the first entry in the logbook was dated February 14, 1999, with a total time in service of 0.4 hours. A conditional inspection signoff followed on March 5, 1999. The following (last) logbook entry was dated May 10, 1999, and showed a total time in service of 25.0 hours.

The engine logbook and documentation showed that the original engine, a Textron Lycoming O-360-A1A, had been overhauled on October 1, 1998. The logbook also showed that the engine was installed on N41VA with 0.0 hours service on January 10, 1999, and was "inspected [and] deemed airworthy" on March 5, 1999. The last logbook entry, dated May 27, 1999, showed a total of 25.6 engine hours.

The overhaul facility, Aero Sport Power, a division of Pro Aero Engines, Inc., of Kamloops, British Columbia, issued serial number 0172 for the engine (refer to ATTACHMENT ASP-I). The engine was purchased, according to an invoice, on October 5, 1998 (refer to ATTACHMENT BOS-I). A parts list associated with the overhaul showed that four new pistons, part number LW15357 as well as four new "Aero Sport" cylinders, part number S441SP, were installed (refer to ATTACHMENT OL-I). In an email dated October 13, 1998, the overhaul facility advised the owner that "high compression pistons are not mentioned separately on the parts list as they are included in the cylinder kits" (refer to ATTACHMENT EM-I).

According to a representative of Textron Lycoming, the standard piston associated with the O-360-A1A engine is part number LW75089. This piston is defined as having a compression ratio of 8.5 to 1 resulting in a horsepower of 180 for this engine. The piston, part number LW15357, which was installed in the RV-8's engine, was associated with a later version of the O-360 engine and has a compression ratio of 9.0 to 1.

An Internet website (address: http://www.matronics.com/cgi-bin/searching/ws_script.cgi) was reviewed and a search of all emails related to the pilot's name and/or aircraft registration number was made with 288 hits received. The first hit was dated September 1998 and the last hit (the last email issued by the pilot prior to the accident) was dated July 8, 1999, and referenced 35 hours of RV-8 time. There was no evidence in any of these emails that the pilot had attempted any major engine disassembly or removed any of the engine's cylinders. Additionally, a fellow RV-8 builder at the Independence airport, who was in close contact with the pilot during the construction of N41VA, reported that he saw no evidence of the pilot's attempting any major engine disassembly or removal of any of the engine's cylinders.

A representative from TransWestern Aviation, Inc., the fixed base operator and fuel supplier at the Scappoose airport, Scappoose, Oregon, confirmed that N41VA was fueled on the afternoon of July 10, 1999. According to a fueling slip, the aircraft was topped off with 25.4 gallons of 100 aviation octane low lead fuel approximately 1345.

Meteorological information

The aviation surface weather observation taken at 1553 at McMinnville, Oregon, four nautical miles south of the accident site, reported clear sky conditions, a temperature of 90 degrees Fahrenheit, and winds from 330 degrees magnetic at 7 knots.

Wreckage and impact information

The aircraft crashed in an agricultural field on gently rolling terrain approximately one nautical mile north of Lafayette, Oregon. The accident site coordinates were determined using a hand-held GPS unit and were found to be 45 degrees 15.65 minutes north latitude and 123 degrees 6.48 minutes west longitu