NTSB Identification: MIA99LA133.
The docket is stored in the Docket Management System (DMS). Please contact Records Management Division
Accident occurred Monday, April 19, 1999 in THOMASTOWN, MS
Probable Cause Approval Date: 03/31/2000
Aircraft: Bell 47G-3B1, registration: N32PH
Injuries: 2 Uninjured.

NTSB investigators may not have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.

The pilot stated he was pulling up the aerial spray rigged helicopter from the platform of the 'nurse truck' in order to reposition for a better placement on the platform, when he experienced uncommanded rotation. His ground crew stated, as he pulled up, a piece of the aircraft flew off and the tail rotor began to spin down. The aircraft went into an uncontrollable rotation, and the main rotor blades collided with an adjacent small tree stand. The helicopter impacted the terrain, the right landing skid collapsed, and the helicopter rolled over on its right side. Subsequent examination of the wreckage and interviews of the pilot, passenger, and ground crew revealed the approach and pull up for the second approach were into downwind conditions. The piece of the aircraft that flew off was a section of the tail rotor drive shaft. Except for the missing piece of shaft, no mechanical abnormalities could be found in the pilot controls, engine, or drive train.

The National Transportation Safety Board determines the probable cause(s) of this accident to be:

An in-flight loss of control caused by the main rotor severing the tail rotor drive shaft as a result of the pilot's cyclic pull-up into a tailwind for his second approach and landing. The loss of the tail rotor caused an uncontrollable descent and tree strike with the main rotor and in-flight collision with terrain. Contributing to the accident was the pilot's improper decision to make a downwind approach and landing.

Full narrative available

Index for Apr1999 | Index of months