McDonnell Douglas 369D N33CN

Summary

On 11 November 1995 at about 01:45 local time, a McDonnell Douglas 369D registered N33CN was involved in an accident near Mather, California, 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

11 November 1995 at 01:45

Classification

Accident

Location

Mather, California, United States

Nearest airport

Sacramento Mather (MHR)

Coordinates

38.5401, -121.2800

Aircraft

McDonnell Douglas 369D

Registration

N33CN

Category

Helicopter

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Public Use

Phase of flight

Not recorded

Aircraft damage

Substantial

Weather

VMC

Light

Night/Dark

NTSB number

LAX96TA044

2 people had minor injuries.

Fuel starvation due to the right seat safety pilot's inadvertent engine shutdown when he closed the throttle to simulate an engine failure, and his failure to perform the throttle rigging check before takeoff. Contributing to the accident was the improper rigging of the throttle system coupled with the pilot's improper recovery from the autorotation.

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

Read the full NTSB narrative

The left seat pilot was practicing night autorotations to runway 22 to maintain his currency. After the left seat pilot completed six hovering autorotations to the ground and eight autorotations to a power recovery, the right seat pilot snapped the right collective throttle to the ground idle position at 250 feet in a climb, to simulate a loss of engine power and announced 'power failure.' The left seat pilot initiated an autorotation; neither pilot was aware of an actual loss of power. When the left seat pilot applied throttle to initiate a power recovery, the engine's compressor stalled and the 'engine out' and 'auto re-ignite' lights illuminated. The left seat pilot continued with the autorotation, landed on runway 22 with the tail-first, broke the skids, and the aircraft rolled over. The investigation revealed that the right seat pilot did not perform the throttle rigging check before departing on the accident flight as recommended by the 369D pilot handbook. Several postaccident ground runs of the engine were conducted. Based upon those, it was determined that rapid roll off of the right seat throttle could retard the throttle below ground idle and flameout the engine. The throttle misrigging had not been detected by maintenance personnel.

Quoted verbatim from the NTSB record.