LAX98LA162

NTSB accident investigation · Schweizer G164D · Richvale, CA · May 17, 1998

Accident · No injuriesLimited investigationFinal report
Date
May 17, 1998, 11:30 local (18:30 UTC)
Place
Richvale, CA
Injuries
1 uninjured
Damage
Destroyed
Phase of flight
Initial climb
Aircraft
N8177KSchweizer G164D
Weather
Visual (VMC) · Day
Status
Completed · report February 11, 2000
Report
Approved by Office Director
FAA report
19980517009779A
Case key
30088

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

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Probable cause

The separation of four compressor/turbine blades resulting in a sudden loss of engine power with a subsequent forced landing into unsuitable 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.

Loss of engine power(total) - mech failure/malfTakeoff - initial climb
Compressor assembly,blade - failureCause
Misc,engine compressor stall/surgeFactor
Forced landingEmergency descent/landing
Nose overEmergency landing after takeoff
Terrain condition - softFactor

Analysis

On takeoff, the pilot experienced a loss of engine power preceded by the sound of loud 'pop.' He completed a forced landing on soft ground and the aircraft nosed over. During the post-accident teardown inspection of the engine, it was noted that four compressor/turbine blades had failed at the blade/butt interface. The failed blades were not standard manufacturer's replacement parts.

Factual narrative

On May 17, 1998, at 1130 hours Pacific daylight time, a Schweizer G164D, N8177K, was destroyed when it nosed over during a forced landing following a total loss of engine power on takeoff. The commercial pilot was not injured and there was no property damage. At the time of the accident, the flight was departing the Doc Thompson airstrip which is located 9 miles north-northwest of Richvale, California. Visual meteorological conditions prevailed and no flight plan was filed for the 14 CFR Part 137 agricultural application flight.

The operator stated in his accident report that, approximately 15 feet agl, he heard a loud "pop" in the engine compartment followed by an immediate loss of engine power. He made a forced landing to a soft dirt field about 800 feet from the end of the runway.

During a teardown inspection of the engine, it was noted that four compressor/turbine blades were broken off at the blade/butt interface. The parting surface on the butt side of the break was clean and did not show evidence of progressive failure. It was also noted that the four broken blades were not standard manufacturer's replacement parts.

Aircraft

Registration
N8177K
Reported as
Schweizer G164D
Category
Airplane
Serial number
8D
Airframe hours
9,628
Engine
P&W PT6A-34AG, 750 horsepower, turbo prop
Damage
Destroyed
Flight
Aerial application · Part 137
Registered owner
Avag, Incorporated
Airworthiness certificate
Special, Restricted (Special)
Last inspection
Annual · April 25, 1998 · 62 hours before
Departed
PVT · CA
Airport
Thompson Strip, runway 16, 2,000 × 30 ft, asphalt

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
57
Certificate
Commercial
Airplane ratings
Multi-engine land, Single-engine land
Instrument ratings
Airplane
Medical
Class 2, Valid Medical--w/ waivers/lim
Seat
Front
Flight hours
37,000 total · 8,000 in this make and model · 50 in the last 90 days · 50 in the last 30 days · 8 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
280° at 8 knots
Visibility
60 statute miles
Lowest ceiling
None
Temperature
70 °F, dew point 46 °F
Altimeter
30.00 inHg
Observed at
CIC, 18 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.