# NTSB FTW94LA181: Mooney M20J, N50105, Willcox, AZ, May 26, 1994 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: May 25, 1994, 18:00 local (May 26, 1994, 01:00 UTC) - Place: Willcox, AZ - Coordinates: 32.430141, -109.880523 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=32.4301&lon=-109.8805&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report December 7, 1994 - Report: Approved by Office Director - NTSB case key (mKey): 19073 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW94LA181 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/19073/pdf - Page: https://openairdocs.org/ntsb/FTW94LA181 ## Probable cause THE FAILURE OF THE CONNECTING ROD DUE TO LACK OF LUBRICATION. FACTORS WERE THE PREVIOUS DAMAGE TO THE ENGINE, AND THE UNSUITABLE TERRAIN AT THE PILOT'S DISPOSAL 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 - powerplant - previous damage (contributing factor) - lubricating system,oil port/passage,internal - blocked(total) (cause) - engine assembly,connecting rod - failure,total (cause) - Forced landing, descent - emergency - On ground/water collision with object, landing - roll - object - tree(s) - terrain condition - rough/uneven - terrain condition - none suitable (contributing factor) ## Analysis THE PROPELLER RPM SURGED AND AS THE PILOT ATTEMPTED TO REDUCE POWER, THE ENGINE VIBRATED VIOLENTLY AND STOPPED WHEN THE THROTTLE WAS CLOSED. A FORCED LANDING WAS MADE TO A MESQUITE AND SAGE BRUSH COVERED DESERT. DURING ROLLOUT THE AIRCRAFT IMPACTED SEVERAL LARGE CLUSTERS OF MESQUITE AND A FENCE RESULTING IN SUBSTANTIAL DAMAGE TO BOTH WINGS AND HORIZONTAL STABILIZERS. EXAMINATION OF THE 580 HOUR ENGINE REVEALED THAT TWO CONNECTING RODS HAD FAILED DUE TO LACK OF LUBRICATION. A BEARING WAS FOUND TO HAVE SPUN, BLOCKING THE ENGINE OIL FLOW. THE AIRPLANE HAD BEEN INVOLVED IN AN INCIDENT 108 HOURS PRIOR TO THE ACCIDENT IN WHICH THE ENGINE WAS OPERATED WITH LOW OIL QUANTITY AND LOW OIL PRESSURE. ## Factual narrative On May 25, 1994, at 1800 Pacific daylight time, a Mooney M20J, N50105, was substantially damaged during a forced landing near Willcox, Arizona. The instrument rated private pilot was not injured. Visual meteorological conditions prevailed for the business flight. An IFR flight plan was filed for a flight from Fort Stockton, Texas, to Scottsdale, Arizona. The pilot reported that he was in cruise flight at an assigned altitude of 10,000 feet, when "he noticed a change in engine and propeller sound, accompanied by the propeller RPM increasing beyond the red line." Propeller control could not be regained by moving the propeller control lever, and "when the power was reduced, the engine began to shake violently." When the pilot closed the throttle, the engine stopped. After declaring an emergency, and establishing a glide to the Cochise County Airport, near Willcox, Arizona, the pilot attempted to restart the engine with the starter without success. The pilot further stated that the airport was beyond the gliding distance of the airplane, and a forced landing was attempted on the rough and uneven desert, "pretty well covered by mesquite and brush." The right main landing gear was torn from the wing during the landing roll. Both wings and horizontal stabilizers sustained substantial damage due to a collision with mesquite trees and a fence. A detailed examination of the 580 hour engine revealed that the 3 and 4 connecting rods had failed due to lack of lubrication. A bearing was found to have spun, blocking the oil flow. According to the aircraft and engine records, an incident involving the operation of the engine with low oil occurred approximately 108 hours prior to the accident. The details of the incident are enclosed in the pilot/operator report. ## Aircraft - Registration: N50105 (not matched to a registry record) - Reported make and model: MOONEY M20J - Category: Airplane - Serial number: 24-3059 - Airframe hours: 572 - Engines: LYCOMING IO-360 200 horsepower reciprocating - Damage: Substantial damage - Flight: Business, Part 91 - Registered owner: Lucht, Orren J - Airworthiness certificate: Standard, Normal - Last inspection: Annual, May 11, 1994, 13 hours before - Departed: FST, FORT STOCKTON, TX - Destination: SDL, SCOTTSDALE, AZ - Flight plan: IFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 67; private; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: left; flight hours: 1,568 total, 1,100 in this make and model, 1,336 as pilot in command, 15 in the last 90 days, 11 in the last 30 days, 4 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 310° at 8 knots - Visibility: 40 statute miles - Lowest ceiling: 6,500 ft broken - Temperature: 73 °F, dew point 48 °F - Altimeter: 29.00 inHg - Observed at: TUS, 60 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 19940525018769A](https://openairdocs.org/incident/19940525018769A), May 25, 1994: Mooney M20J, Willcox, AZ, Substantial damage. Runway prop and vibration at cruise. Landed rough desert. Crankshaft bearing spun. Blocked oil. Broke two rods. 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.