ASN Wikibase Occurrence # 354864
This information is added by users of ASN. Neither ASN nor the Flight Safety Foundation are responsible for the completeness or correctness of this information.
If you feel this information is incomplete or incorrect, you can
submit corrected information.
Date: | Thursday 22 January 1998 |
Time: | 12:15 LT |
Type: | Hughes 269C |
Owner/operator: | Private |
Registration: | N1093N |
MSN: | 100882 |
Year of manufacture: | 1980 |
Total airframe hrs: | 2829 hours |
Engine model: | Lycoming HIO-360-D1A |
Fatalities: | Fatalities: 0 / Occupants: 2 |
Aircraft damage: | Substantial |
Category: | Accident |
Location: | Brackettville, TX -
United States of America
|
Phase: | En route |
Nature: | Unknown |
Departure airport: | Bacon Ranch, TX |
Destination airport: | |
Investigating agency: | NTSB |
Confidence Rating: | Accident investigation report completed and information captured |
Narrative:The pilot and a crewmember/gunner of the public use helicopter reported hearing a loud squealing noise, emanating from the rear of the helicopter, while in flight at 75 feet AGL. Rotor RPM began decaying from 3,100 to approximately 2,000 RPM, and the pilot initiated an autorotation. During the landing, the main rotor blades contacted the ground, and helicopter came to rest in a rocky dry creek bed on its right side. The tension nut for the short shaft was found upstream from the point of impact. An examination revealed that splines for the drive shaft coupling were damaged, and the plating on the adapter was discolored as result of excessive heat. Further examination revealed that the damage sustained by the shaft and adapter were consistent with loss of grease and subsequent overheating and destruction of the drive splines. The forward rubber boot, used to retain the lubricant, had separated, resulting in the loss of lubrication.
Probable Cause: failure of splines on the drive shaft coupling after separation of the forward bubber boot and loss of lubrication (grease), which resulted in a disconnect of the rotor drive system and an autorotation/forced landing. Lack of suitable terrain in the forced landing area was a related factor.
Accident investigation:
|
| |
Investigating agency: | NTSB |
Report number: | FTW98TA104 |
Status: | Investigation completed |
Duration: | 9 months |
Download report: | Final report |
|
Sources:
NTSB FTW98TA104
Location
Revision history:
Date/time | Contributor | Updates |
11-Mar-2024 19:11 |
ASN Update Bot |
Added |
The Aviation Safety Network is an exclusive service provided by:
CONNECT WITH US:
©2024 Flight Safety Foundation