19910331007939A

Accident · Substantial damage

FAA accident report · Bell 47G-2 · Waitsburg, WA · March 31, 1991

Date: March 31, 1991 · 08:15 local
Place: Waitsburg, WA
Phase of flight: Idling Rotors
Operating rules: Agricultural (Part 137)
Operator: WPMG
Damage: Substantial damage
Aircraft: N38926
NTSB investigation: NTSBSEA91LA077
Reported as: Bell 47G2
Reported engine: Lycoming VO435A1F
People aboard: 1
Fatal injuries: 0
Pilot’s flight hours: 8,000 total8,000 in this make and model150 in the last 90 days

N38926Registration cancelled Nov 14, 2012 · Bell 47G-2S/N N.A.H.1957-1 · Built 1973 Airframe modelBell 47G-2 Engine modelLycoming VO-435 seriesReciprocating

From the FAA’s Accident/Incident Data System (AIDS), through its Aviation Safety Information Portal, as reported. The NTSB investigates accidents separately, and its record of an accident is the fuller one. The aircraft is matched to the registry by N-number and event date, checked against the reported make and model; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

What happened

The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.

Main rotor separated from mast just after touchdown. Lock washers not properly installed on recent maintenance.

As the FAA filed it

MAIN ROTOR SEPARATED FROM MAST JUST AFTER TOUCHDOWN. LOCK WASHERS NOT PROPERLY INSTALLED ON RECENT MAINTENANCE.

NTSB investigation

The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.

NTSB SEA91LA077Accident · No injuriesLimited investigationFinal reportWaitsburg, WAThe improper installation of the main rotor mast nut and lock washer by maintenance personnel which resulted in the separation of the main rotor system.Mar 31, 1991 · Substantial damage

Other reports on N38926 · 5

Matched to the same aircraft by N-number and date.

Accident 20050704014629AFcd/Prec Ldg From Cruise · Oroville, WA(-23) While involved in aerial application, suffered sudden, complete loss of power. Autorotation initiated to cherry orchard nw of area being sprayed. Main rotor involved cherry trees and hard landing followed. There was no post impact fire.Jul 4, 2005 · Substantial damage Accident 19770919027669ATo Running(Helicopter/Vtol Ac) · Mountain View, ARLow downwind turn after liftoffSep 19, 1977 · Destroyed Accident 19760717022919ALow Level Operations · Mcallen, TXPlt un arrest sink rate,had to lnd.Jul 17, 1976 · Substantial damage Accident 19750526014279ALow Level Operations · Denmark, ARBell yoke tail rotor hub p/n 47-641-057-009 failed.May 26, 1975 · Substantial damage Accident 19730406007229AHovering · Owatonna, MNFAA production test flt.13 lbs over max gross wt,fwd CG limit,60 lbs over max cabin load. Lost ctl.Apr 6, 1973 · Substantial damage