# NTSB FTW95LA065: Commonwealth Rearwin 185, N93290, Longmont, CO, December 12, 1994 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: December 12, 1994, 13:30 local (20:30 UTC) - Place: Longmont, CO - Coordinates: 40.17081, -105.109733 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=40.1708&lon=-105.1097&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report February 24, 1995 - Report: Approved by Office Director - NTSB case key (mKey): 19321 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW95LA065 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/19321/pdf - Page: https://openairdocs.org/ntsb/FTW95LA065 ## Probable cause OIL EXHAUSTION AND SUBSEQUENT ENGINE SEIZURE DUE TO A MISSING OIL DRAIN PLUG. FACTORS WERE THE INADEQUATE MAINTENANCE AND THE LACK OF SUITABLE TERRAIN FOR A 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, approach - vfr pattern - downwind - lubricating system,oil quickdrain/drain plug - missing (cause) - maintenance,overhaul,major - inadequate, other maintenance personnel (contributing factor) - fluid,oil - exhaustion - powerplant - seized - Forced landing, descent - emergency - On ground/water encounter with terrain/water, landing - roll - terrain condition - none suitable (contributing factor) - terrain condition - rough/uneven ## Analysis WHILE ON THE DOWNWIND LEG, THE ENGINE 'SPUTTERED' AND THE PILOT IMMEDIATELY TURNED TOWARDS THE RUNWAY. THE ENGINE THEN SEIZED AND THE PROPELLER STOPPED TURNING. UNABLE TO GLIDE TO THE AIRPORT, THE PILOT MADE A FORCED LANDING IN AN OPEN FIELD. DURING THE LANDING ROLL, THE AIRPLANE STRUCK A DEPRESSION AND THE LANDING GEAR WAS TORN OFF. POST-ACCIDENT EXAMINATION DISCLOSED THE OIL DRAIN PLUG WAS MISSING AND THERE WAS NO EVIDENCE OF OIL IN THE CRANKCASE. THE ENGINE HAD ACCUMULATED FIVE HOURS TIME-IN- SERVICE SINCE UNDERGOING A MAJOR OVERHAUL. ## Factual narrative On December 12, 1994, approximately 1330 mountain standard time, N93290, a Commonwealth Rearwin 185, was substantially damaged during a forced landing in Longmont, Colorado. The commercial pilot was not injured. Visual meteorological conditions prevailed. The following is based on the pilot report. The pilot planned to practice touch and go landings. After takeoff and while on the downwind leg, the engine "sputtered" and he immediately turned towards the runway. The engine then seized and the propeller stopped turning. Unable to glide to the airport, the pilot made a forced landing in an open field. During the landing roll, the airplane struck a depression and the landing gear was torn off. After examining the airplane, a Federal Aviation Administration inspector reported the oil drain plug was missing and there was no evidence of oil in the crankcase. The engine had accumulated five hours time-in-service since undergoing a major overhaul. ## Aircraft - Registration: [N93290](https://openairdocs.org/aircraft/N93290), registered now, S/N 1854, built 1946 (OpenAirDocs) - Reported make and model: COMMONWEALTH REARWIN 185 (REARWIN 18) - Registry model: [Commonwealth REARWIN 185](https://openairdocs.org/model/commonwealth-rearwin-185) (registry code 2370604) (OpenAirDocs) - Registry engine: [Continental C85 series](https://openairdocs.org/engine/continental-c85-series) (registry code 17008, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 1854 - Airframe hours: 1788 - Engines: CONTINENTAL C-85-12 85 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Epp, Robert W. - Registered owner: Epp, Robert W./Shroyer, Jami - Airworthiness certificate: Standard, Normal - Last inspection: Annual, December 10, 1994, 5 hours before ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 48; commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 2, valid medical--no waivers/lim.; seat: left; flight hours: 2,479 total, 1 in this make and model, 2,300 as pilot in command, 55 in the last 90 days, 5 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Visibility: 50 statute miles - Lowest ceiling: none - Temperature: 45 °F ## 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 19941212041569A](https://openairdocs.org/incident/19941212041569A), Dec 12, 1994: Comwth REWN185, Longmont, CO, Substantial damage. Engine miss on downwind. Siezed. Landed off airport. Oil drain plug missing. No oil. Five hrs since major overhaul. ## Other investigations on N93290 (1) 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. - [NTSB LAX72DUJ45](https://openairdocs.org/ntsb/LAX72DUJ45), Sep 20, 1971: Commonwlth 185 (N93290), Mesa, AZ, substantial damage 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.