Cessna 172 N7188A

Summary

On 27 June 1998 at about 13:05 local time, a Cessna 172 registered N7188A was involved in an accident near Flagstaff, Arizona, United States. One person was on board and nobody was injured. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

27 June 1998 at 13:05

Classification

Accident

Location

Flagstaff, Arizona, United States

Nearest airport

Flagstaff Pullman (FLG)

Coordinates

Not recorded

Aircraft

Cessna 172

Registration

N7188A

Category

Airplane

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Aircraft damage

Substantial

Weather

VMC

Light

Dawn

NTSB number

LAX98LA214

Nobody was injured.

Oil system contamination with an unidentified metal substance that traveled through the oil system and blocked the number 4 main bearing and number 6 connecting rod bearing oil ports, resulting in oil starvation and failure of the engine. The source of the contamination is undetermined.

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

Read the full NTSB narrative

The pilot stated that the preflight and run-up were conducted with no anomalies noted. After takeoff, the airplane experienced a loss of engine power followed by a loss of altitude and collision with terrain. The airplane came to rest inverted in a sewage pond near the airport. After the power loss, the pilot made an unsuccessful attempt to restart the engine utilizing the emergency checklist. The engine was inspected and mechanical continuity of the engine was established. The crankcase was separated and it was noted that the bearings, pistons, and cylinders exhibited heat discoloration. The number 4 main bearing exhibited evidence of rubbing on the crankshaft and a section of that bearing insert was severely worn, heat distressed, and had flowed over the edge of the crankcase bearing journal. The number 6 connecting rod bearing insert exhibited an unidentified metal substance in the oil port. The remaining crankcase oil journals were found to be clear. The oil pump was disassembled and revealed a nick on one of the driven gear teeth, which corresponded to circumferential scoring on the oil pump housing. The oil filter and suction screen were clean. No further discrepancies were noted with the engine. Review of the maintenance records revealed that an annual inspection, which included an oil change, had been completed approximately 1 hour prior to the accident flight.

Quoted verbatim from the NTSB record.