Enstrom 280C N5692P

Summary

On 27 March 1988 at about 23:45 local time, a Enstrom 280C registered N5692P, operated by Pegasus Aviation Corporation, was involved in an accident near Fremont, California, United States. 2 people were 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 March 1988 at 23:45

Classification

Accident

Location

Fremont, California, United States

Coordinates

Not recorded

Aircraft

Enstrom 280C

Registration

N5692P

Category

Helicopter

Engines

1

Operator

Pegasus Aviation Corporation

Operating rule

Part 91: General Aviation

Purpose of flight

Instructional

Phase of flight

Not recorded

Route

Palo Alto → Unknown

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

LAX88FA140

Nobody was injured.

FAILURE OF THE ENGINE TO MAIN ROTOR DRIVE SYSTEM DUE TO A DRIVE BELT SLIPPAGE CAUSED BY A DRIVE PULLEY WORN BEYOND ITS SERVICE LIMIT. CONTRIBUTING TO THE ACCIDENT WAS THE INADEQUATE FACTORY MAINTENANCE MANUALS WHICH DID NOT PROVIDE THE SERVICEABLE LIMITS FOR THE DRIVE BELT PULLEYS.

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

Read the full NTSB narrative

WHILE WORKING IN THE TRAFFIC PATTERN ON A LOCAL INSTRUCTIONAL FLIGHT, THE CFI NOTICED THE MAIN ROTOR RPM WAS BELOW THE GREEN ARC. HE ENTERED AN AUTOROTATION AND TRIED UNSUCCESSFULLY TO GET THE ROTOR RPM BACK INTO THE GREEN ARC. THE HELICOPTER COLLIDED WITH THE GROUND DURING THE ATTEMPTED AUTOROTATION WITH A LOW MAIN ROTOR SPEED. INVESTIGATION REVEALED THAT THE ENGINE DRIVE PULLEY WAS WORN BEYOND THE FACTORY ESTABLISHED LIMIT, WHICH ALLOWED THE DRIVE BELT TO SLIP. THE MINIMUM SERVICEABLE WEAR LIMIT FOR THE DRIVE PULLEY WAS NOT PUBLISHED IN THE FACTORY MAINTENANCE PROCEDURES.

Quoted verbatim from the NTSB record.