- Date
- April 22, 2000, 15:00 local (20:00 UTC)
- Place
- Lawrenceburg, TN
- Injuries
- 1 uninjured
- Damage
- Substantial damage
- Phase of flight
- Maneuvering
- Aircraft
- N6096PAir Tractor AT-401-B
- Weather
- Visual (VMC) · Day
- Status
- Completed · report March 2, 2001
- Report
- Approved by Office Director
- FAA report
- 20000422012689A
- Case key
- 49030
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 loss of engine power due to a stuck exhaust valve that resulted in the collision with a tree while maneuvering for the forced 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 stated that, while on an aerial application run, he heard a loud pop and observed black smoke coming from the engine exhaust. The pilot selected an area for a forced landing. While maneuvering for the landing, the airplane collided with trees. Examination of the engine disclosed that, the number 3 cylinder's exhaust valve was stuck in the open position
Factual narrative
On April 22, 2000, at 1500 central daylight time, an Air Tractor AT-401-B, N6096P, collided with trees while maneuvering for a forced landing near Lawrenceburg, Tennessee. The aerial application flight was operated by Thornton Aerial Application under the provisions of 14 CFR Part 137, with no flight plan filed. Visual weather conditions prevailed at the time of the accident. The airplane sustained substantial damage, and the commercial pilot was not injured. The flight departed Lawrenceburg, Tennessee, at 1450.
The pilot stated that he had made an application run and was pulling up when he heard a loud pop and observed black smoke coming from the engine exhaust system. The pilot selected an area for a forced landing, and while maneuvering for the landing, the airplane collided with trees. According to the pilot, "due to the low altitude of this type of operation a suitable landing spot could not be chosen."
During a subsequent examination of airframe systems, the carburetor model NAY91E1 S/N 5962942 was installed on another engine and tested for proper operation. The engine was operated at 700, 1200, 1400, 1600, and 2000 rpm for five minutes at each point. The engine was leaned with the mixture control and a normal magneto check was performed. The propeller lever was also cycled to various rpm. All operations of the carburetor were normal. Examination of the engine off of the airplane, S/N ZP10053, revealed that the number 3 cylinder's exhaust valve was stuck in the open position.
Weather conditions reported in the area at the time of the accident were favorable for the formation of carburetor ice as indicated by the icing probability curves chart.
Aircraft
- Registration
- N6096P
- Reported as
- Air Tractor AT-401-B
- Category
- Airplane
- Serial number
- 0999
- Engine
- P&W R-1340, 600 horsepower, reciprocating
- Damage
- Substantial damage
- Flight
- Aerial application · Part 137
- Registered owner
- Thornton Aerial Application
- Airworthiness certificate
- Special, Restricted (Special)
- Flight plan
- Unknown
- Airport
- 2M2 · Lawrence County Airport, runway 35, 4,800 × 100 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
- 30
- Certificate
- Commercial
- Airplane ratings
- Single-engine land
- Medical
- Class 2, Valid Medical--no waivers/lim.
- Seat
- Front
- Flight hours
- 4,120 total · 1,315 in this make and model · 3,984 as pilot in command · 38 in the last 90 days · 21 in the last 30 days
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 310° at 8 knots
- Visibility
- 10 statute miles
- Lowest ceiling
- 25,000 ft broken
- Temperature
- 66 °F, dew point 39 °F
- Altimeter
- 29.00 inHg
- Observed at
- BNA, 75 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.