# NTSB SEA05FA004: Maule MT-7-420, N186SB, Bend, OR, October 8, 2004 - Type: NTSB accident investigation - Classification: Accident · No injuries · Field investigation · Final report - Date: October 8, 2004, 14:00 local (21:00 UTC) - Place: Bend, OR - Coordinates: 44.083332, -121.20111 - Nearby events: https://openairdocs.org/map.md?lat=44.0833&lon=-121.2011&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report September 13, 2005 - Report: Approved by Office Director - Parties: FAA/FSDO, Rolls-Royce - NTSB case key (mKey): 60316 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA05FA004 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/60316/pdf - Page: https://openairdocs.org/ntsb/SEA05FA004 ## Probable cause Loss of engine power during takeoff climb for undetermined reasons. Rough terrain was a factor. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power, takeoff - initial climb - reason for occurrence undetermined (cause) - Forced landing, takeoff - aborted - Nose over, landing - roll - terrain condition - rough/uneven (contributing factor) ## Analysis The pilot rated passenger reported that the start, taxi, run-up, and initial take-off were normal. The aircraft departed on runway 16 and attained an altitude of 150 to 300 feet above ground level when the engine lost power. The PIC announced that he was landing straight ahead. The aircraft touched down left of the runway edge at the departure end and traveled over rough terrain before nosing over and coming to rest inverted. During post-accident airframe and engine inspections, no evidence of a mechanical failure or malfunction was found. ## Factual narrative HISTORY OF FLIGHT On October 8, 2004, about 1400 Pacific daylight time, a Maule MT-7-420, N186SB, registered to Shotgun Ranch Aviation LLC, and flown by the owner of the company as a 14 CFR Part 91 personal flight, experienced a loss of engine power shortly after takeoff from Bend Municipal, Bend, Oregon. The pilot-in-command (PIC) aborted the takeoff and landed the aircraft near the departure end of the runway. During the landing roll over rough terrain off the end of the runway, the aircraft nosed over and came to rest inverted. Visual meteorological conditions prevailed at the time and no flight plan was filed. The aircraft was substantially damaged and the commercial pilot and pilot rated passenger were not injured. The flight was departing for Prineville, Oregon, at the time. During a telephone interview and subsequent written statement, the pilot rated passenger reported that the start, taxi, run-up, and initial take-off were normal. The aircraft departed on runway 16 and attained an altitude of 150 to 300 feet above ground level when the engine lost power. The PIC announced that he was landing straight ahead. The aircraft touched down left of the runway edge at the departure end and traveled over rough terrain before nosing over and coming to rest inverted. PERSONNEL INFORMATION At the time of the accident, the pilot-in-command held a commercial certificate for single and multi-engine land aircraft with an instrument rating. The pilot reported a total flight time in all aircraft of 2,100 hours with 1,874 hours as pilot-in-command. A total of 9.4 hours had been accumulated in the Maule. The pilot-rated passenger held commercial, airline transport and a flight instructor certificate in single-engine land and sea, and multi-engine land, with an instrument rating. The pilot reported a total flight time in all aircraft of 9,606 hours with 6,165 hours as pilot-in-command. A total of 1.9 hours had been accumulated in the Maule. AIRCRAFT INFORMATION The airframe a model MT-7-420, serial number 51001C, N186SB, was manufactured by Maule Air, Inc., in February 2004. A normal standard airworthiness certificate was issued on August 17, 2004, at an airframe total time of 35.6 hours. The airframe was designed to accommodate a Rolls Royce turbine engine model 250-B17C, serial number CAE-880102. Maintenance records indicated that the engine was overhauled and assembled from previously parted out turbine, utilizing customer supplied parts in new or overhauled condition by Metro Aviation, Shreveport, LA, at a total engine time of 3,883.9 hours in October 2003. At the time of the accident, both the airframe and engine (since major overhaul) had accumulated a total time of 75.1 hours. The operator reported that the company took possession of the aircraft at 49.5 hours and had flown it 25.6 hours since receiving the aircraft. Maintenance personnel for the company reported two maintenance discrepancies since receipt of the aircraft. The first was a leak in the propeller which resulted in a logbook entry on 9/14/04, at 54.8 hours, which stated, "Resealed beta tube in prop piston." The other discrepancy reported was a "chip light" which resulted in the detection of a particle of metal, which was removed. The mechanic made a call to a representative of Rolls Royce which indicated that that was normal right after an overhaul. No date was given as to when this occurred, and there is no logbook entry. The second pilot reported that the aircraft had sat in the hangar for about two weeks prior to the accident flight. This was the first flight since the chip light detection. Maintenance personal also reported that the aircraft uses Jet A with Prist pre-mixed additive. TESTS AND RESEARCH On October 18, 2004, investigators from the National Transportation Safety Board, Federal Aviation Administration and Rolls-Royce inspected the engine at Specialty Aircraft, Redmond, Oregon. During the engine inspection and teardown, no evidence of a failure was noted to any of the engine modules or accessories. Both the wet and dry sides of the fuel system displayed integrity. Dirt and debris was found in the compressor, discharge tubes and turbine section. The propeller assembly was inspected and found that all three propeller blades remained attached to the hub. Propeller blade "A" displayed leading and trailing edge nicks from about mid span. Chordwise polishing was noted to the blade back. The blade was bent aft about 80 degrees. Propeller blade "B" displayed an approximate 20 degree aft bending. Chordwise polishing was noted to the blade back. Propeller blade "C" displayed and approximate 90 degree aft bending. Chordwise polishing was noted to the blade back. The fuel control unit, overspeed governor and propeller governor were removed for further testing and sent to Woodward Aircraft Engine Systems, Rockford, Illinois. All three units tested within specification parameters. ADDITIONAL INFORMATION Components removed for testing were returned to Keystone Helicopter, Coatesville, PA, on April 26, 2005. ## Aircraft - Registration: [N186SB](https://openairdocs.org/deregistered/N186SB-2012-08-09), registration cancelled 2012-08-09, S/N 51001C, built 2004 (OpenAirDocs) - Reported make and model: Maule MT-7-420 - Registry model: [Maule MT-7-420](https://openairdocs.org/model/maule-mt-7-420) (registry code 5460192) (OpenAirDocs) - Registry engine: [Allison 250 series](https://openairdocs.org/engine/allison-250-series) (registry code 03019, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 51001C - Airframe hours: 75 - Engines: Rolls-Royce 250-B17C 420 horsepower turbo prop - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Shotgun Ranch Aviation LLC - Airworthiness certificate: Standard, Normal - Last inspection: Annual, August 17, 2004, 40 hours before - Departed: S07, Bend, OR - Destination: Prineville, OR - Airport: S07, Bend Municipal, runway 16, 5,005 × 75 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 54; injuries: none; commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; last flight review August 11, 2004; seat: left; flight hours: 2,100 total, 9 in this make and model, 1,874 as pilot in command - Other flight crew; injuries: none ## Weather - Conditions: Visual (VMC), Day - Wind: 240° at 10 knots, gusting 17 - Visibility: 10 statute miles - Temperature: 77 °F, dew point 41 °F - Altimeter: 29.79 inHg - Observed at: RDM, 10 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 20041008035409A](https://openairdocs.org/incident/20041008035409A), Oct 8, 2004: Maule MT7420, Bend, OR, Substantial damage. (-23) Accident still under investigation. Mechanical components to be evaluated for internal failures by manufacturer. Result to be forthcoming. 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.