Robinson R44 N8329B

Summary

On 17 July 2003 at about 20:05 local time, a Robinson R44 registered N8329B was involved in an accident near Happy Jack, Arizona, 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

17 July 2003 at 20:05

Classification

Accident

Location

Happy Jack, Arizona, United States

Coordinates

34.8281, -111.1889

Aircraft

Robinson R44

Registration

N8329B

Category

Helicopter

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Flagstaff → Payson

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

LAX03LA235

Nobody was injured.

the partial loss of engine power due to an excessively lean mixture for undetermined reasons during cruise flight.

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

Read the full NTSB narrative

The engine lost power during cruise flight, and the helicopter collided with high vegetation during an autorotative descent. Just before touchdown during the forced landing, engine power was restored; however, the pilot decided to concentrate on successfully completing the forced landing. The helicopter touched down in high vegetation and was substantially damaged. The power loss was not preceded by any auditory or visual warnings, and none occurred during the descent. Following recovery of the helicopter from the remote site, the engine was visually examined then placed into a test cell and run up. During the first engine run, the engine exhibited the following results: (1) normal start; (2) normal warm-up; (3) lean operation upon accelerating between 2,250 and 2,300 rpm with no fuel boost pump on; (4) upon turning on the test cell's fuel boost pump, the engine accelerated between 2,700 and 2,800 rpm with no hesitation. During the second engine run, with a carburetor from another Lycoming O-540 engine, the accident engine operated normally during run up to full power without the test cell's fuel boost pump turned on. Thereafter, the accident carburetor was examined, including a flow bench test, and no abnormalities were found that would have prevented the carburetor from functioning within prescribed design specifications. The reason for the excessively lean mixture/restricted fuel flow, which reduced the engine's available power, was not ascertained.

Quoted verbatim from the NTSB record.