# NTSB FTW95LA174: Cessna T210L, N1664X, Estancia, NM, April 19, 1995 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: April 18, 1995, 20:30 local (Apr 19, 1995, 02:30 UTC) - Place: Estancia, NM - Coordinates: 34.759544, -106.060218 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=34.7595&lon=-106.0602&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed, report October 19, 1995 - Report: Approved by Office Director - NTSB case key (mKey): 19399 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW95LA174 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/19399/pdf - Page: https://openairdocs.org/ntsb/FTW95LA174 ## Probable cause THE LOSS OF ENGINE POWER DUE TO EXHAUST VALVE SEPARATION RESULTING FROM INADEQUATE MAINTENANCE. A FACTOR WAS THE DARK NIGHT AND THE LACK OF SUITABLE TERRAIN FOR THE FORCED LANDING. ## 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 - normal - engine assembly,valve,exhaust - separation (cause) - maintenance - inadequate, other maintenance personnel (cause) - Forced landing, emergency descent/landing - In flight collision with object, emergency descent/landing - terrain condition - none suitable (contributing factor) - object - wire,transmission - object - tree(s) - object - fence - light condition - dark night (contributing factor) - In flight collision with terrain/water, descent - uncontrolled ## Analysis DURING THE FORCED LANDING, FOLLOWING A TOTAL LOSS OF ENGINE POWER, IN DARK NIGHT CONDITIONS, THE AIRPLANE STRUCK TRANSMISSION WIRES AND TREES BEFORE COMING TO REST INVERTED ALONG A FENCE ROW. EXAMINATION OF THE ENGINE REVEALED A HOLE IN THE #2 PISTON. PHYSICAL EVIDENCE INDICATED THAT THE EXHAUST VALVE MIGRATED OUT THE EXHAUST. METAL PARTS, FOUND IN THE OIL SUMP, WERE IDENTIFIED AS PARTS OF THE #2 EXHAUST VALVE SEAT. ENGINE S/N 217105R WAS OVERHAULED IN MARCH, 1992; HOWEVER, RECORDS DID NOT INDICATE THAT THE VALVES HAD BEEN CHANGED AT THE OVERHAUL. ACCORDING TO THE MANUFACTURER REPRESENTATIVE, 'GUIDELINES FOR AN ENGINE OVERHAUL REQUIRE CHANGING THE VALVE.' THE ENGINE WAS SUBSEQUENTLY REMOVED AND REASSEMBLED IN AUGUST, 1993, AND IN FEBRUARY, 1994. ## Factual narrative On April 18, 1995, at 2030 mountain daylight time, a Cessna T210L, N1664X, collided with trees, transmission wires, and a fence during a forced landing near Estancia, New Mexico. The commercial pilot received minor injuries and the airplane sustained substantial damage. Visual meteorological conditions prevailed for the Title 14 CFR Part 135 on demand cargo cross country flight and a VFR flight plan was filed. The operator was B & M Enterprises, Inc., dba New Mexico Flying Service of Albuquerque, New Mexico. During personal interviews, conducted by the Federal Aviation Administration (FAA) inspector, with the pilot, and a review of Albuquerque Air Route Traffic Control Center (ABQ ARTCC) data, the information in this paragraph was revealed. En route from Alamogordo, New Mexico, at 2016, radar contact was established and VFR flight following was received. At 2026, the pilot reported a total loss of engine power and declared an emergency. The controller issued the location and distance to the nearest lighted airport. Radar contact was lost at 2029; however, at 2031 the pilot transmitted that the landing would be in a field. Dark night conditions precluded visual contact with the terrain. On final approach, with the landing light on, a tree and houses were observed. At 50 feet above the ground, the pilot deviated to avoid the houses; however, the airplane descended through power lines and impacted the terrain. The airplane came to rest inverted along a fence row. Structural damage occurred to the left horizontal stabilizer, rudder, fuselage,and wings. An examination by the FAA inspector and the manufacturer representative revealed a hole in the #2 piston. The #2 cylinder exhaust valve head was separated from the valve stem and the head was not located. Physical evidence indicated that the exhaust valve head migrated out the exhaust. Metal parts, found in the oil sump, were identified as parts of the #2 exhaust valve seat. Damage was noted to the turbine section of the turbocharger. A review of the maintenance records revealed the following information. Engine S/N 217105R was overhauled in March, 1992; however, records did not show that the valves had been changed at the overhaul. According to the manufacturer representative, "guidelines for an engine overhaul require changing the valves." Records further indicated that the engine was removed in August, 1993, due to a cracked case and subsequently reassembled. Cylinders #4 and #6 were replaced in November, 1993, and a compression check conducted in December, 1993, indicated "68" for cylinder #2. The engine was again removed, disassembled, and reassembled in February, 1994, with the #4 cylinder being replaced, and in September, 1994, the #3 cylinder was replaced. On January 28, 1995, the last recorded maintenance record of an engine compression check indicated below "60" for 4 of the 6 cylinders. ## Aircraft - Registration: [N1664X](https://openairdocs.org/deregistered/N1664X-1997-02-19), registration cancelled 1997-02-19, S/N 21060699 (OpenAirDocs) - Reported make and model: CESSNA T210L - Registry model: [Cessna T210L](https://openairdocs.org/model/cessna-t210l) (registry code 2073449) (OpenAirDocs) - Category: Airplane - Serial number: 21060699 - Airframe hours: 5743 - Engines: CONTINENTAL TSIO-520-H 285 horsepower reciprocating - Damage: Substantial damage - Flight: Part 135 - Operator: B & M Enterprises, Inc., doing business as New Mexico Flying Service - Registered owner: Billy J. Ware - Airworthiness certificate: Standard, Normal - Last inspection: Annual, March 30, 1995, 35 hours before - Departed: HMN, ALAMOGORDO, NM - Destination: ABQ, ALBUQUERQUE, NM - Flight plan: VFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 25; commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--w/ waivers/lim; seat: left; flight hours: 1,746 total, 505 in this make and model, 1,555 as pilot in command, 230 in the last 90 days, 57 in the last 30 days, 2 in the last 24 hours ## Weather - Conditions: Visual (VMC), Night/dark - Wind: 180° at 9 knots - Visibility: 40 statute miles - Temperature: 59 °F, dew point 12 °F - Altimeter: 29.00 inHg - Observed at: ABQ, 28 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 19950418036299A](https://openairdocs.org/incident/19950418036299A), Apr 18, 1995: Cessna T210L, Estancia, NM, Substantial damage. Lost power at night. Struck wires landing. Nosed over. Hole in NR2 piston and broken exhaust valve. 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.