- Date
- December 18, 2002, 15:21 local (23:21 UTC)
- Place
- Los Banos, CA
- Injuries
- 2 uninjured
- Damage
- Substantial damage
- Phase of flight
- Maneuvering
- Aircraft
- N642KCSchweizer 269C
- Weather
- Visual (VMC) · Day
- Status
- Completed · report December 28, 2004
- Report
- Approved by Office Director
- Parties
- Lycoming, Schweizer, Federal Aviation Administration
- FAA report
- 20021218034469A
- Case key
- 56218
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
The improper engine overhaul by other maintenance personnel, which resulted in an exhaust valve failure and a total loss of engine power while in maneuvering flight.
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
The pilot and aircraft maintenance technician were performing a post maintenance test flight when a vibration occurred, followed by a total loss of engine power. The commercial certificated helicopter pilot made a forced landing in a muddy field, during which the helicopter received structural damage. Post accident examination revealed a failed exhaust valve in the number 3 cylinder, and that two exhaust spring seats had been installed, one on top of the other, causing excessive spring/valve pressures. The engine had been overhauled about 1.5 service hours prior to the loss of engine power.
Factual narrative
On December 18, 2002, at 1521 Pacific standard time, a Schweizer 269C, N642KC, experienced a total loss of engine power and rolled over during a forced landing in a muddy field at Los Banos, California. The helicopter was operated by the pilot under 14 CFR Part 91. The commercial pilot and one passenger were not injured. The helicopter was substantially damaged. Visual meteorological conditions prevailed, and no flight plan had been filed. The flight originated at Los Banos about 1500.
The pilot and aircraft maintenance technician were performing a post maintenance test flight when a vibration occurred followed by a total loss of engine power. Post accident examination revealed a failed exhaust valve in the number 3 cylinder. Further examination revealed two exhaust spring seats had been installed, one on top of the other, causing excessive spring/valve pressures. The operator had just overhauled the engine; the failure occurred about 1.5 hours after the overhaul.
Aircraft
- Registration
- N642KC
- Reported as
- Schweizer 269C
- Category
- Helicopter
- Serial number
- S1682
- Airframe hours
- 3,784.6
- Engine
- Avco Lycoming HIO-360-D1A, 200 horsepower, reciprocating
- Damage
- Substantial damage
- Flight
- Personal · Part 91
- Registered owner
- John Raven
- Airworthiness certificate
- Standard, Normal
- Last inspection
- 100 hour · August 23, 2002 · 1.5 hours before
- Departed
- LSN · Los Banos, CA
- Airport
- LSN · Los Banos
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
- 48
- Injuries
- None
- Certificates
- Private, Flight instructor, Commercial
- Airplane ratings
- Single-engine land
- Medical
- Class 2, Valid Medical--w/ waivers/lim
- Seat
- Left
- Flight hours
- 1,900 total
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 10° at 3 knots
- Visibility
- 10 statute miles
- Lowest ceiling
- None
- Temperature
- 54 °F, dew point 37 °F
- Altimeter
- 30.20 inHg
- Observed at
- MCE, 22 nm away
FAA reports on this event · 1
The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.