- Date
- May 3, 1991, 19:00 local (May 4, 1991, 02:00 UTC)
- Place
- Delano, CA
- Injuries
- 1 uninjured
- Damage
- Substantial damage
- Phase of flight
- Enroute
- Aircraft
- N4414Hiller UH-12E
- Weather
- Visual (VMC) · Day
- Status
- Completed · report January 25, 1993
- Report
- Approved by Office Director
- FAA report
- 19910503014169A
- Case key
- 27187
From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.
On this page
Probable cause
That the pilot improperly performed the autorotation by misjudging the flare altitude. Contributing to this accident was the total failure of the freewheeling sprag clutch due to excessive wear and the soft dirt terrain.
Sequence of events
NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.
Analysis
Shortly after lifing off a privately owned airstrip the engine experienced an overspeed condition. The pilot executed an autorotation into an open field. During the autorotation the pilot misjudged the flare altitude, landed hard causing the main rotor blades to severe the tailboom assembly. The helicopter rolled over onto its left side as the forward left skid dug into the soft terrain.
Aircraft
- Registration
- N4414
- Reported as
- Hiller UH-12E
- Category
- Helicopter
- Serial number
- 2205
- Airframe hours
- 12,556
- Engine
- Lycoming VO-540-C2A, 305 horsepower, reciprocating
- Damage
- Substantial damage
- Flight
- Aerial application · Part 137
- Operator
- San Joaquin Helicopters Inc.
- Registered owner
- San Joaquin Helicopters Inc
- Last inspection
- Annual · April 11, 1991 · 18 hours before
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.
Flight crew
As NTSB recorded them. NTSB leaves out names.
- Role
- Pilot
- Age
- 37
- Certificate
- Commercial
- Airplane ratings
- Single-engine land
- Medical
- Class 2, Valid Medical--w/ waivers/lim
- Flight hours
- 1,000 total · 38 in this make and model · 960 as pilot in command · 58 in the last 90 days · 30 in the last 30 days · 3 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Day
- Visibility
- 15 statute miles
- Lowest ceiling
- None
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 N4414 · 2
Matched to the same aircraft by N-number and date.