Eurocopter AS355N N355CV

Summary

On 28 May 2004 at about 14:35 local time, a Eurocopter AS355N registered N355CV was involved in an accident near League City, Texas, United States. 6 people were on board and 4 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

28 May 2004 at 14:35

Classification

Accident

Location

League City, Texas, United States

Coordinates

29.5194, -95.2386

Aircraft

Eurocopter AS355N

Registration

N355CV

Category

Helicopter

Engines

2

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Pearland → Houston

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

FTW04FA143

4 people had minor injuries.

"THIS CASE WAS MODIFIED MAY 30, 2006." The pilot's misjudged flare during an autorotation, which resulted in a hard landing and subsequent rollover.

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

Read the full NTSB narrative

"THIS CASE WAS MODIFIED MAY 30, 2006." The 13,800-hour airline transport pilot and five passengers departed on a short pleasure flight after satisfactorily completing a maintenance check with the engines running on the ground. The pilot flew to a local airport and made a normal straight-in approach, executed an autorotation with a power recovery, then proceeded back to the home airport. While en route, after the helicopter crossed over a large row of power lines, the pilot reported the helicopter lost all engine power. However, none of the anticipated aural warnings, annuciator lights, abnormal vibrations or sounds associated with a power failure was observed. The pilot entered an autorotation and the helicopter contacted the ground hard and rolled over. Examination of the helicopter revealed continuity to all flight controls and the main gearbox. The #1 engine was placed on a test cell, started immediately, and was run at various power settings without interruption. Due to impact damage the #2 engine could not be test-run. Examination of the #1 and #2 engines' main gearbox coupling shafts by an NTSB Materials Specialist revealed that the shafts were both fractured at the reduced section adjacent to the main gear box input splines. The fracture plane, presence of dimpling, and direction of fracture were consistent with ductile torsional overstress with the engines running. In addition, data retrieved from the digital engine control units and damage to the main gear drive shafts indicated that both engines were operating at the time of impact. No mechanical deficiencies were noted that would have attributed to a loss of power on either engine. Several attempts were made to obtain a copy of NTSB Form 6120.1/2, Pilot/Operator Accident Report; however, the pilot failed to submit a completed report.

Quoted verbatim from the NTSB record.