# NTSB NYC97LA035: Cessna T210M, N732UH, Lexington, KY, December 21, 1996 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: December 20, 1996, 21:00 local (Dec 21, 1996, 02:00 UTC) - Place: Lexington, KY - Coordinates: 38.069759, -84.580261 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=38.0698&lon=-84.5803&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 1 minor, 4 uninjured - Status: Completed, report October 31, 1997 - Report: Approved by Office Director - NTSB case key (mKey): 39314 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=NYC97LA035 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/39314/pdf - Page: https://openairdocs.org/ntsb/NYC97LA035 ## Probable cause failure of #5 exhaust valve and/or #5 exhaust valve guide, which resulted in a progressive engine failure (debris puncturing the #5 piston crown, exhaust gasses entering the crankcase, loss of oil through the breather system, oil exhaustion, and subsequent damage to the engine bearings and connecting rods). Darkness and obstructions (vehicles) in the emergency landing area were related factors. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(total) - mech failure/malf, cruise - engine assembly,valve,exhaust - failure,total (cause) - engine assembly,piston - penetrated - fluid,oil - exhaustion - engine assembly,bearing - failure - engine assembly,connecting rod - failure - Forced landing, emergency descent/landing - On ground/water collision with object, emergency landing - light condition - bright night (contributing factor) - object - vehicle (contributing factor) ## Analysis The Cessna 210 was cruising at 11,000 ft at night, when the engine began to run rough & lose power. The pilots attempted to fly to an airport with suitable services, but all engine power was lost. The pilots then performed a forced landing on a divided highway. During the landing, two vehicles were struck. Examination of the airplane & engine revealed oil on the underside of the fuselage & a hole on the top of the engine case. Further examination revealed the #5 exhaust valve guide had fractured just below the flange that seated the guide into the cylinder head, with evidence of fatigue. The #5 exhaust valve was fractured between the valve head & stem; but the cause of this fracture could not be determine due to impact damage to the fractured surfaces. The #5 intake valve was also partially broken, but fracture of this valve appeared to have been from overload, due to impact with debris inside the cylinder. Also, the #5 piston crown was found mutilated, & a hole was broken through the crown to the interior. Additionally, the main bearings and connecting rod bearings were damaged due to a lack of lubrication, and the #2 and #4 connecting rods had failed. ## Factual narrative On December 20, 1996, about 2100 eastern standard time, a Cessna T210M, N732UH was substantially damaged during a forced landing on a highway, and subsequent collision with two vehicles in Lexington, Kentucky. The two pilots and two passengers on the airplane were not injured, while a third passenger received minor injuries. The occupants of the two vehicles were not injured. Night visual meteorological conditions prevailed for the flight which departed Birmingham, Alabama, at 1847. The flight was conducted on an instrument flight plan under 14 CFR Part 91. The airplane owner held a private pilot certificate, occupied the left seat, and was operating the flight controls. A commercial rated flight instructor occupied the right seat. The owner reported that they were cruising at 11,000 feet, 15 to 20 miles northeast of Lexington, when the engine began to run rough and a partial power loss occurred. The owner advised air traffic control, and requested to land at the Blue Grass Airport in Lexington. About 5 miles northeast of Lexington, the engine lost total power and the pilot positioned the airplane for a forced landing to a divided highway. During the forced landing, the airplane passed over the top of a power line, and then went under a highway overpass. The airplane struck two vehicles moving in the same direction as the airplane, and then came to rest on the highway. Both pilots reported that oil was visible on the underside of the fuselage. The airplane was examined by a Federal Aviation Administration (FAA) Airworthiness Inspector, who reported that a hole was found in the top of the crankcase near the number four cylinder. Further inspection revealed the number four connecting rod cap was separated from the connecting rod which disconnected the rod from the crankshaft. The engine was shipped to Teledyne Continental Motors (TCM), Mobil, Alabama, for further examination. The examination was conducted for the Safety Board by a FAA inspector assigned to TCM. According to the TCM report: "...Crankcase main bearings exhibited oil starvation signatures...Number 5 exhaust valve, part number SA643873 broken in the transition of the head to the valve stem...could not determine cause of fracture due to extreme impact damage to the fractured surfaces. " "The number 4 exhaust guide, part number SA636242 was broken just below the flange that seats the guide into the cylinder head. The fracture exhibited fatigue...." "Number 5 intake valve, part number SA539988 head was partially broken up. Most pieces of the valve head were not recovered. The fracture of this valve appears all overload due to impact with debris inside the cylinder." ## Aircraft - Registration: [N732UH](https://openairdocs.org/aircraft/N732UH), registered now, S/N 21061781, built 1977 (OpenAirDocs) - Reported make and model: Cessna T210M - Registry model: [Cessna T210M](https://openairdocs.org/model/cessna-t210m) (registry code 2073451) (OpenAirDocs) - Registry engine: [Continental TSIO-520 series](https://openairdocs.org/engine/continental-tsio-520-series) (registry code 17040, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 21061781 - Airframe hours: 2924 - Engines: Continental TSIO-520-R 310 horsepower reciprocating - Damage: Substantial damage - Flight: Business, Part 91 - Operator: Daniel N. Garon - Registered owner: Pointe Flyers, Inc - Airworthiness certificate: Standard, Normal - Last inspection: Annual, October 31, 1996, 56 hours before - Departed: BHM, BIRMINGHAM, AL - Destination: 22B, ELYRIA, OH - Flight plan: IFR - Airport: LEX, Blue Grass, runway 22, 7,002 × 150 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 27; flight instructor, commercial, private; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: right; flight hours: 1,775 total, 56 in this make and model, 1,690 as pilot in command, 200 in the last 90 days, 50 in the last 30 days, 7 in the last 24 hours ## Weather - Conditions: Visual (VMC), Night/bright - Wind: 170° at 5 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 14 °F, dew point 7 °F - Altimeter: 30.00 inHg - Observed at: LEX, 4 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 (OpenAirDocs). - [Accident 19961220039799A](https://openairdocs.org/incident/19961220039799A), Dec 20, 1996: Cessna T210M, Lexington, KY, Substantial damage. (.4)On December 20, 1996, about 2100 eastern standard time, a Cessna T210M,N732UH was substantially damaged during a forced landing on a highway, and… From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.