IAD96LA091

During a local flight, the pilots observed oil accumulating on the windscreen and felt vibration of the airplane. They returned to the departure airport, but came in too high and fast on the approach to land, so they attempted a go-around. Although the pilot applied full throttle for the go-around, it '...resulted in little [additional] power and very high vibration.' As the pilot performed a left turn, the engine lost power completely. The airplane impacted trees and shrubs during the forced landing. Examination of the engine found that the 'P' lead insulation on both magnetos had deteriorated and intermittently grounding the magnetos. The FAA Inspector stated that the 'P' leads were probably 'original equipment' on the airplane, which was manufactured in 1959. He also stated that the 'P' lead condition could have resulted in the magnetos 'grounding out,' resulting in loss of engine power. The most recent annual inspection of the airplane was completed almost 14 months before the accident. The pilot did not have a current medical certificate or biennial flight review.

On June 5, 1996, at about 1700 eastern daylight time, a Piper PA-24-180 "Comanche", N5984P, lost engine power while attempting a go-around at the New Carlisle Airport, New Carlisle, Ohio. The airplane sustained substantial damage when it descended into a field and impacted trees and shrubs. The pilot and the pilot rated passenger sustained minor injuries. Visual meteorological conditions prevailed, and no flight plan was filed. The local flight was conducted under 14 CFR Part 91.

The 72 year old private pilot/airplane owner stated that the purpose of the flight was to flight test the aircraft before selling it. He reported that his biennial flight review was expired, and his most recent medical certificate was issued in 1956. He stated that when he flew his airplane, he always had a qualified pilot in the airplane with him. The private pilot/airplane owner stated that on the day of the accident, he performed the flight test with an experienced "Comanche" pilot in the left seat to assist him if needed.

The private pilot/airplane owner wrote that they took off to the west into a mild 10 mile-per-hour (mph) wind. He indicated that the takeoff was normal until they were on the cross wind leg at about 400 feet above ground level (agl), when both pilots noticed a mild vibration. He wrote that as they continued the climb, the vibration smoothed out, so they proceeded to fly to a practice area. After about 10 minutes in the practice area, the pilots noticed oil on the windshield and at about the same time a vibration developed again. They returned to the airport at reduced power and entered an extended traffic pattern, due to airplane traffic already in the pattern.

The pilot stated that the airplane was high and fast when they turned towards the landing strip, and at about mid field he elected to attempt to go-around. The private pilot/airplane owner applied full throttle, which "...resulted in little [additional] power and very high vibration... ." Shortly thereafter, as the pilot attempted to turn the airplane back to the airport, the engine lost power completely. The airplane impacted the ground in a field adjacent to the airport, and a small fire developed below the left magneto. The pilots exited the airplane and extinguished the fire.

The Federal Aviation Administration (FAA) Airworthiness Inspector reported that postaccident investigation revealed a light film of oil on the right side of the windshield and the nosewheel fork, but no evidence of oil on the fuselage or engine firewall. He had the engine transported to T.W. Smith Engine Company in Cincinnati, Ohio, for further examination. The inspector stated that no attempt was made to run the engine as the crankshaft flange was damaged by the impact. Examination of the aircraft's log books by the FAA Inspector, showed that the aircraft had its most recent annual inspection on April 20, 1995, and that the accident flight was the first flight in two years.

The FAA Inspector stated that examination revealed that the insulation on the left and right magneto "P" leads had broken up into powder allowing the grounding wires to intermittently ground out the magnetos. According to the FAA Inspector, the "P" leads were probably original equipment in the 1959 model airplane, and this would have accounted for the roughness and subsequent loss of engine power described by the pilot/owner of the aircraft.