Beechcraft 95-B-55 N27WF

Summary

On 26 March 1989 at about 21:30 local time, a Beechcraft 95-B-55 registered N27WF, operated by Casebolt, FON, was involved in an accident near Crothersville, Indiana, United States. 2 people were on board and 2 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

26 March 1989 at 21:30

Classification

Accident

Location

Crothersville, Indiana, United States

Coordinates

38.7909, -85.8396

Aircraft

Beechcraft 95-B-55

Registration

N27WF

Category

Airplane

Engines

2

Operator

Casebolt, FON

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Louisville → Louisville

Aircraft damage

Substantial

Weather

VMC

Light

Dawn

NTSB number

CHI89LA063

2 people had minor injuries.

A FAILURE OF THE ENGINE DUE TO A CRANKSHAFT COUNTERWEIGHT FAILURE. THE PILOT PERFORMED EMERGENCY PROCEDURES AND EXECUTED A FORCED LANDING IN AN OPEN FIELD, WHERE THE AIRCRAFT ENCOUNTERED A LARGE MUDDY AREA, BOGGED DOWN AND NOSED OVER.

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

Read the full NTSB narrative

DURING A LOCAL PLEASURE FLIGHT, WHILE IN NORMAL CRUISE, THE RIGHT ENGINE FAILED TOTALLY. THE PILOT REDUCED POWER ON THE LEFT (OPERATING) ENGINE TO 'CURTAIL THE VIOLENT VIBRATION OF THE AIRCRAFT' AND EXECUTED A FORCED LANDING IN AN OPEN FIELD. AS THE AIRCRAFT WAS ROLLING OUT AFTER TOUCHDOWN, IT ENCOUNTERED A MUDDY AREA. THE NOSE GEAR BOGGED DOWN, THEN COLLAPSED, AND THE AIRCRAFT NOSED OVER. POST-ACCIDENT EXAMINATION OF THE RIGHT ENGINE REVEALED THAT THE PIN RETAINING PLATE CUT THROUGH THE CRANKSHAFT COUNTERWEIGHT, RELEASING IT. FURTHER EXAMINATION REVEALED THAT THE COUNTERWEIGHTS HAD NOT BEEN 'TUFTRIDED', A SURFACE HARDENING PROCESS WHICH PREVENTS THE PIN RETAINING PLATE FROM CUTTING/WEARING THROUGH THE COUNTERWEIGHT. THIS PROCESS HAS BEEN REQUIRED ON NEW ENGINES SINCE 1968, AND ON REBUILT ENGINES SINCE 1973-74. THE ACCIDENT ENGINE WAS REBUILT BY THE MANUFACTURER IN 1971. LOGBOOK/MAINTENANCE INFORMATION PROVIDED BY THE PILOT WAS INCOMPLETE.

Quoted verbatim from the NTSB record.