Cessna 172 N8299U

Summary

On 13 October 1996 at about 19:12 local time, a Cessna 172 registered N8299U was involved in an accident near Germantown, Kentucky, United States. One person was on board and one had minor injuries. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

13 October 1996 at 19:12

Classification

Accident

Location

Germantown, Kentucky, United States

Coordinates

38.6501, -83.9602

Aircraft

Cessna 172

Registration

N8299U

Category

Airplane

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Cincinnati → Prestonsburg

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

IAD97LA008

1 person had minor injuries.

improper maintenance with the installation of an improper oil ring on the number four piston, which led to failure of both the ring and pistion, oil starvation, and subsequent loss of engine power.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full NTSB narrative

The flight was en route at 5500' MSL, when the pilot noted a loss of oil pressure followed by a loss of engine power. A forced landing was made in an open field, where the airplane collided with a ditch. Inspection of the airplane revealed the lower fuselage was covered with oil. Examination of the engine revealed evidence of oil starvation in the main bearings, connecting rod bearings, and journals of the crankshaft. All of the cylinders were steel-barreled, except the #4 cylinder, which was chrome plated. The #4 cylinder was heavily scored in the chrome barrel, and the #4 piston was scored completely around its skirt. The #4 piston exhibited burning on the lower crown, which eroded a hole to the piston interior below the third piston ring groove. The piston rings were stuck due to aluminum from the piston skirts extruding over them. Heat had expanded the piston skirts into contact with the cylinder walls, scoring them and transferring aluminum from the piston skirt. According to a report from the manufacturer, chrome cylinders must use plain steel rings per TCM service literature; however, the #4 cylinder was installed using rings for a steel barreled cylinder, which have chrome plating on the top compression ring. The manufacturer's report also noted that chrome ring on chrome cylinder bore will not work and could create scoring, metal transfer, and eventually severe blowby conditions. The engine had accumulated 1075 hours of flight time since the last overhaul.

Quoted verbatim from the NTSB record.