CHI99LA275
1999-07-28 · LA FAYETTE, Illinois, United States · None · 1 aircraft · Status: Completed
Current FAA registration · N15345
- Make / Model
- FAIRCHILD 24 C8C
- Year of manufacture
- 1935 · 64 years old at event
- Engine
- WARNER SS40&50 (90 hp)
- Seats / Engines
- 3 seats · 1 engine
- Last airworthiness date
- 19560712
- ADS-B equipped
- Yes — Mode-S A0D856
Source: FAA Aircraft Registry (releasable master file).
Aircraft involved
Probable cause & findings
the pilot's failure to obtain/maintain the proper descent rate. A factor to the accident was the partial loss of engine power as a result of the exhaust valve keeper becoming unlocked, which jammed the exhaust valve.
Factual narrative
On July 28, 1999, at 1500 central daylight time, a Fairchild 24 C8C, N15345, piloted by an Airline Transport Pilot, sustained substantial damage during a forced landing following a loss of engine power during cruise flight, near La Fayette, Illinois. Visual meteorological conditions prevailed at the time of the accident. The personal flight was operating under the provisions of 14 CFR Part 91 and was not on a flight plan. The pilot and one passenger reported no injuries. The flight departed Hannibal Municipal Airport, Hannibal, Missouri, at 1340 and was en route to Dacy Airport, Harvard, Illinois, at the time of the accident. The pilot reported that, during cruise flight, at 3,000 feet mean sea level (msl), he noticed a substantial amount of engine oil on the right windshield. The pilot stated that, approximately one minute after noticing the oil, the engine's rpm began to drop continuously. The pilot decided to make a precautionary landing at the Kewanee Municipal Airport, Kewanee, Illinois, which was 15 nautical miles northeast of his position. The pilot reported that, approximately two minutes after he first noticed the oil on the windshield, the engine began a gradual loss of power, and he described the engine's operation as "grinding." The pilot stated that he positioned the aircraft into the wind, along Illinois State Highway 17, and executed the forced landing onto the State Highway. The pilot stated that he flared, "...as best as energy would allow and skidded 300' to [a] stop." The pilot reported that the flare, "...would not completely arrest [the] sink rate causing [the] gear to collapse." Post accident inspection of the engine revealed a crack in the head of the number two cylinder. Cylinder number two's rocker-arm cover was removed, revealing that the exhaust valve stem keeper had become unlocked, allowing the valve to drop down into the cylinder's bore. The exhaust valve stem was found to be jammed in its guide. The pilot reported that, during cruise flight, at 3,000 feet mean sea level, he noticed a substantial amount of engine oil on the right windshield. The pilot stated that, approximately one minute after noticing the oil, the engine's rpm began to drop continuously. The pilot reported that, approximately two minutes after he first noticed the oil on the windshield, the engine began a gradual loss of power. The pilot stated that he positioned the aircraft into the wind and executed a forced landing onto a State Highway. The pilot stated that he flared 'as best as energy would allow and skidded 300' to [a] stop.' The pilot reported that the flare 'would not completely arrest [the] sink rate causing [the] gear to collapse.' Post accident inspection of the engine revealed a crack in the head of the number two cylinder. Cylinder number two's rocker-arm cover was removed, revealing that the exhaust valve stem keeper had become unlocked, allowing the valve to drop down into the cylinder's bore. The exhaust valve stem was found to be jammed in its guide. Source: NTSB Aviation Accident Database (Pre-2008 Archive) Retrieved: 2026-02-12
Verbatim from NTSB's published report. Source file
NTSB_1999_CHI99LA275.txt.
Findings + structured fields enriched from FAA avall.mdb.
Full investigation docket on
data.ntsb.gov ↗.
Search this event elsewhere
External sources are reported, not agency: signal that something happened, not fact about what happened.
- TallyAero Live Wire Aviation press
- NTSB CAROL Agency ↗
- NTSB Docket Agency ↗
- Aviation Safety Network Aviation press ↗
- Kathryn's Report Aviation press ↗
- Aviation Herald Aviation press ↗
- AVweb Aviation press ↗
- Pilots of America Community ↗
- Reddit /r/flying Community ↗
- FlightAware Aviation press ↗
- AOPA accident database Aviation press ↗
- Google News News ↗
- DuckDuckGo News ↗
Related research
Matched on aircraft type or causal vocabulary (icing). All research papers
- arXiv 2026 · arXiv preprint Enabling Beyond-Visual-Line-of-Sight Drones Operation over Open RAN 5G Networks with Slicing
Among the foretold claims of the transition from 5G to 6G, Beyond-Visual-Line-of-Sight (BVLoS) drone operation has emerged as a prominent Internet-of-Robots enabler.
- NASA NTRS 2026 · Contractor Report (CR) Icing Physics Studies Using the 3D SIDRM Test Article: 2023 Icing Tests Analysis
In-flight icing is an important safety issue and is a factor that affects aircraft design and performance. Newer regulations are driving a need for improvements in airframe and engine icing simulation…
- arXiv 2025 · arXiv preprint Multi-Agent Deep Reinforcement Learning for UAV-Assisted 5G Network Slicing: A Comparative Study of MAPPO, MADDPG, and MADQN
The growing demand for robust, scalable wireless networks in the 5G-and-beyond era has led to the deployment of Unmanned Aerial Vehicles (UAVs) as mobile base stations to enhance coverage in dense urb…
- NASA NTRS 2025 · Presentation NASA Icing Update – March 2025
This NASA Icing Update was prepared for presentation to the SAE International AC-9C Inflight Icing Technology Committee. This update includes the following topics: planned Rotational Icing Scaling tes…
- Embry-Riddle Scholarly Commons 2025 · Journal article (JAAER) A Mathematical Model on the Temporal Dynamics of Aviation Competitive Pricing
This study investigates the competitive dynamics of airport pricing using U.S. airport data to validate the findings. It employs linear and nonlinear ordinary differential equation models to analyze t…
- arXiv 2024 · arXiv preprint An energy-stable phase-field model for droplet icing simulations
A phase-field model for three-phase flows is established by combining the Navier-Stokes (NS) and the energy equations, with the Allen-Cahn (AC) and Cahn-Hilliard (CH) equations and is demonstrated ana…