CHI98LA326
1998-08-21 · LAMAR, Missouri, United States · None · 1 aircraft · Status: Completed
Airport LLU
N1239Y has since been reassigned. It is now registered to a different aircraft (KITFOX KITFOX SUPER SPORT, built 2016), which was not involved in this event.
Aircraft involved
Probable cause & findings
inadequate lubrication of the torque plate holes and torque pins by the mechanic who performed the airplane's last annual inspection.
Factual narrative
On August 21, 1998, at 1545 central daylight time (cdt), a Cessna 150, N1239Y, piloted by a private pilot, was substantially damaged when it nosed over when it collided with a ditch shortly after departing the left edge of Runway 21 (2,905' X 40', dry asphalt) at the Lamar Municipal Airport, Lamar, Missouri. Visual meteorological conditions prevailed at the time of the accident. The 14 CFR Part 91 flight was not operating on a flight plan. The pilot reported no injuries. The flight departed Pittsburg, Kansas, 1515 cdt. According to the pilot, the wind sock at the landing was "...limp." She said she landed the airplane in a 3-point attitude and was on an uneventful landing roll when the airplane suddenly veered to the left. She said right rudder correction did not stop the turn. The ditch N1239Y collided with was about 30-feet from the runway edge and about 4-feet deep. According to the Federal Aviation Administration Principal Maintenance Inspector (PMI) who examined N1239Y, "...the [left main landing gear's brake] torque plate holes and torque pins were dry... ." The PMI said, "...a person who had assisted in the recovery of the airplane stated that after the airplane was [being] towed... he noted that the left main wheel would not rotate." The PMI said the dry torque plate and pins "...[have] been observed to cause locking of brake assemblies in this inspector's experience." Statements from the mechanic and PMI are appended to this report. The PMI said lubrication of the torque plates and pins normally should take place during the annual inspection and whenever the brakes appear to drag during service. The pilot/owner said she had not experienced any dragging brakes during the time she flew the airplane. The pilot said her landing in the tail wheel airplane was uneventful. During the landing roll, the airplane suddenly veered to the left while in a 3-point attitude. The pilot said right rudder did not stop the turn and the airplane ran off the runway edge and into a 4-foot deep ditch. The on-site investigation revealed that the left main landing gear's brake torque plate holes and torque pins were dry. The wheel would not rotate. According to the pilot, she had never experienced dragging brakes while flying the airplane. Source: NTSB Aviation Accident Database (Pre-2008 Archive) Retrieved: 2026-02-12
Verbatim from NTSB's published report. Source file
NTSB_1998_CHI98LA326.txt.
Findings + structured fields enriched from FAA avall.mdb.
Full investigation docket on
data.ntsb.gov ↗.
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Related research
Matched on aircraft type or causal vocabulary (maintenance). All research papers
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In the field of aviation, safety is a critical cornerstone, and the operation of Unmanned Aerial Vehicle (UAV) systems is deeply connected with this principle.
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With timeliness and efficiency being critical in the aviation maintenance industry, the need has been growing for smart technological solutions that optimize and streamline the different underlying ta…