Hughes 369E N5234Y

Summary

On 22 December 2002 at about 20:45 local time, a Hughes 369E registered N5234Y was involved in an accident near Fritch, Texas, 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

22 December 2002 at 20:45

Classification

Accident

Location

Fritch, Texas, United States

Coordinates

35.7897, -101.9725

Aircraft

Hughes 369E

Registration

N5234Y

Category

Helicopter

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Business

Phase of flight

Not recorded

Route

Syracuse → Gruver

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

FTW03LA066

Nobody was injured.

The loss of engine power due to the failure of the generator input drive-end bearing, which resulted in excessive vibrations that induced a fatigue fracture of the Pc line leading to the engine fuel control unit. A contributing factor was the lack of suitable terrain for the forced landing.

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

Read the full NTSB narrative

The helicopter was damaged during a forced landing after a loss of engine power while in cruise flight. The 14,700-hour pilot stated that at 5,100 feet MSL, the generator warning light illuminated. The pilot switched the generator "OFF" and back "ON" in an attempt to reset it, and was unable to reset the generator. The pilot then recycled the circuit breaker to try to reset the generator, and was still unable to reset the generator. The pilot pulled the generator circuit breaker and aborted the flight. Approximately 15 minutes after the generator failure, the engine out light illuminated and an audio warning came on, engine and rotor RPM started to decay and the pilot initiated autorotation. The auto re-ignition light illuminated during autorotation, but the engine would not spool back up to normal RPM. The pilot continued with the autorotation to a small clearing. During the final phase of the autorotation the pilot performed a cyclic flare to increase rotor RPM and arrest forward movement. The pilot leveled the helicopter a few feet off the ground and pulled the collective to arrest descent, at that point rotor RPM decayed and the helicopter dropped four feet AGL. The helicopter spun approximately 180 degrees from the original heading and impacted the ground nose first, on a heading of 30 degrees. Examination of the generator revealed that its drive-end bearing had failed. Bearing cage pieces fell out during disassembly. A Pc air leak test was performed and a air was detected emanating from the Pc air tube from the power turbine governor (PTG) to the engine fuel control unit (FCU). The tube was fractured approximately 90% circumferentially just above the coupling nut that attaches the tube to the FCU. A new Pc air tube (same part number) was installed and the engine was operated in a test cell. The engine was operated in accordance with the model 250-C20B Production Test Specifications. With the engine in the standard test configuration, response times were within normal limits and the engine met all performance parameters. Further metallurgical examination of the Pc tube revealed evidence of fatigue.

Quoted verbatim from the NTSB record.