- Date
- November 15, 1990, 20:30 local (Nov 16, 1990, 03:30 UTC)
- Place
- Somerton, AZ
- Injuries
- 1 uninjured
- Damage
- Substantial damage
- Phase of flight
- Maneuvering
- Aircraft
- N4441SAir Tractor AT-302
- Weather
- Visual (VMC) · Night/dark
- Status
- Completed · report November 23, 1992
- Report
- Approved by Office Director
- FAA report
- 19901115050889A
- Case key
- 26952
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 failure of the number 3 exhaust valve which led to an engine failure and subsequent crash landing.
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 experienced a loss of engine power and collided with the terrain during a swath run. Examination of the engine revealed the number 3 exhaust valve was cracked. The engine had 266 hours since overhaul and had 20 hours since the last inspection.
Aircraft
- Registration
- N4441S
- Reported as
- Air Tractor AT-302
- Category
- Airplane
- Serial number
- 302-0101
- Airframe hours
- 4,950
- Engine
- P&W R-1340 AN1, 600 horsepower, reciprocating
- Damage
- Substantial damage
- Fire
- On-Ground
- Flight
- Aerial application · Part 137
- Operator
- Kottenbrook, Jeffrey L., doing business as Desert Southwest Sprayers
- Registered owner
- Jeffrey L Kottenbrook
- Airworthiness certificate
- Special, Restricted (Special)
- Last inspection
- Annual · March 1, 1990 · 20 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
- 47
- Certificate
- Commercial
- Airplane ratings
- Single-engine land, Multi-engine land, Single-engine sea
- Instrument ratings
- Airplane
- Medical
- Class 2, Valid Medical--w/ waivers/lim
- Seat
- Front
- Flight hours
- 8,300 total · 5,200 in this make and model
Weather
- Conditions
- Visual (VMC) · Night/dark
- Wind
- Calm
- Lowest ceiling
- None
- Temperature
- 70 °F, dew point 30 °F
- Altimeter
- 30.00 inHg
FAA reports on this event · 1
The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.