- Date
- December 20, 1977
- Place
- Billings, MT · BILLINGS, MT
- Injuries
- 2 minor, 1 uninjured
- Damage
- Destroyed
- Phase of flight
- Enroute
- Aircraft
- N7860SBell 47G3B1
- Status
- Completed · report April 17, 1978
- Report
- Brief approved by the director
- FAA report
- 19771220038559A
- Case key
- 144084
From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.
On this page
NTSB brief
NTSB’s brief of the accident, as it was printed: the coded facts, with the probable cause and factors.
---------------------------------------------------------------------------------------------------------------------------- FILE DATE LOCATION AIRCRAFT DATA INJURIES FLIGHT PILOT DATA F S M/N PURPOSE ---------------------------------------------------------------------------------------------------------------------------- 3-4182 77/12/20 NR.BILLINGS,MT BELL 47G3B1 CR- 0 0 1 NONCOMMERCIAL AIRLINE TRANSPORT, AGE TIME - 1500 N7860S PX- 0 0 2 BUSINESS 45, 17500 TOTAL HOURS, DAMAGE-DESTROYED OT- 0 0 0 700 IN TYPE, NOT INSTRUMENT RATED. DEPARTURE POINT INTENDED DESTINATION BILLINGS,MT LOCAL TYPE OF ACCIDENT PHASE OF OPERATION PROPELLER/ROTOR FAILURE: MAIN ROTOR IN FLIGHT: NORMAL CRUISE HARD LANDING LANDING: POWER-OFF AUTOROTATIVE LANDING PROBABLE CAUSE(S) ROTORCRAFT - TRANSMISSION ROTOR DRIVE SYSTEM: OTHER MISCELLANEOUS ACTS,CONDITIONS - IMPROPER CLEARANCE-TOLERANCE MISCELLANEOUS ACTS,CONDITIONS - EXCESSIVE-WEAR/PLAY MISCELLANEOUS ACTS,CONDITIONS - IMPROPERLY INSTALLED PERSONNEL - MAINTENANCE,SERVICING,INSPECTION: INADEQUATE MAINTENANCE AND INSPECTION EMERGENCY CIRCUMSTANCES - FORCED LANDING OFF AIRPORT ON LAND UNUSUAL NOISE REMARKS- ATTMTD AUTOROTATION DUE LOUD NOISE. COLLECTIVE WAS INOP. WRONG TRANSMISSION INSTALLED.
Aircraft
- Registration
- N7860S
- Reported as
- Bell 47G3B1
- Category
- Helicopter
- Engine
- reciprocating
- Damage
- Destroyed
Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.
FAA reports on this event · 1
The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.
Other investigations on N7860S · 1
Matched to the same aircraft by N-number and date.