Bell UH-1H N114FD

Summary

On 15 October 2003 at about 20:27 local time, a Bell UH-1H registered N114FD was involved in an accident near Sacramento, California, 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

15 October 2003 at 20:27

Classification

Accident

Location

Sacramento, California, United States

Nearest airport

Sacramento Mather (MHR)

Coordinates

38.5564, -121.2833

Aircraft

Bell UH-1H

Registration

N114FD

Category

Helicopter

Engines

1

Operator

Not recorded

Operating rule

Public Use

Purpose of flight

Public Use

Phase of flight

Not recorded

Route

Rancho Murietta → Sacramento

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

LAX04TA018

Nobody was injured.

The loss of engine power due to the fatigue failure of a planetary reduction gear.

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

Read the full NTSB narrative

The helicopter landed hard following a loss of engine power in the traffic pattern. The pilot reported that he picked up the helicopter after maintenance was performed on the audio and visual low rpm warning systems and was positioning the helicopter to back to the airport. As he entered the pattern, he heard a bang and what he described as "a horribly loud grinding sound coming from the rear of the aircraft," and lost engine power. The pilot entered an autorotation to a clear area on the airport. As the helicopter neared the touchdown point, the pilot realized the selected landing area was sloped and so he increased collective to extend the glide to reach a flat area. The helicopter landed hard. A teardown and examination of the engine disclosed that the type and degree of damage to the engine was indicative of the separation of a portion of a planetary reduction gear, which resulted in a piece of inlet housing entering the compressor. This resulted in damage to the compressor airfoils and a loss of power. The separation of the portion of planetary reduction gear was determined to be the result of a fatigue fracture emanating from the aft root corner of one gear tooth. The root cause of the fatigue fracture could not be determined due to smearing of the initiation site. The planetary gears installed in the engine were military direct purchase breakout parts. The engine manufacturer does not approve of the use of military direct purchase hardware in FAA certified or military surplus engines used in public-use operations.

Quoted verbatim from the NTSB record.