Casualties unknown

1997-09-11: Mooney M20F (N6417Q) — John J. Kelly — Coral Springs, FL

Coral Springs, FL, US

On September 11, 1997, a Mooney M20F (registration N6417Q) operated by John J. Kelly was involved in an aviation accident near Coral Springs, FL. Investigators recorded the probable cause as: The engine failure was due to fatigue of the No. 3 cylinder connecting rod and piston pin end plugs, combined with a particle found in the oil passage of the crankshaft for the No. 1 crankpin. Additionally, the No. 3 and No. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.

Sourcesthe U.S. National Transportation Safety Board (NTSB) historical archivePrimary reportUpdated 1781061362Data APIEditorial standards

Shortly after takeoff, an airplane experienced oil pressure fluctuations and a loud engine noise, then crashed into a pond. The pilot was rescued but later died. Investigation revealed fatigue failure of connecting rod components and a particle in the oil passage.

Sequence of Events

About 5 to 10 minutes after takeoff, while climbing through 1,000 to 1,500 feet on a northerly heading with the landing gear retracted, a passenger—who is an A&P mechanic—first noted that the oil pressure dropped to zero and then returned to the green arc. At that time, the airplane was abeam the point where it eventually crashed. The pilot noted the oil pressure fluctuation and began orbiting the area. Shortly after, a loud sound was heard from the engine. While descending with the landing gear extended, the airplane descended into a man-made pond, right wing low. The airplane then cartwheeled and sank in about 17 to 20 feet of water.

Occupant Outcome

The passenger exited the airplane out the main cabin door. The pilot did not escape and was rescued about 12 minutes later but died in a hospital days after the accident.

Engine Examination

The airplane was recovered and an examination of the engine revealed that the No. 3 cylinder connecting rod and piston pin end plugs failed due to fatigue. Additionally, a particle was found in the oil passage way of the crankshaft for the No. 1 crankpin. The investigation also discovered that the No. 3 and No. 1 cylinder pistons were installed in the opposite cylinders.

Maintenance History

The engine was last inspected in accordance with a 100-hour inspection about 39 hours, and 2 months and 10 days before the accident. The engine was a factory new engine installed on July 21, 1993, in accordance with a Supplemental Type Certificate. Requests were made following the accident to examine the maintenance records, but they were not provided. Copies of the maintenance records were first provided to the National Transportation Safety Board 1 year and 11 months after the accident by the engine manufacturer, who obtained them from an attorney related to the case.

Probable cause

The engine failure was due to fatigue of the No. 3 cylinder connecting rod and piston pin end plugs, combined with a particle found in the oil passage of the crankshaft for the No. 1 crankpin. Additionally, the No. 3 and No. 1 cylinder pistons were installed in the opposite cylinders.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001208X08893. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.