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October 8, 2004 · Maule MT-7-420 · N186SB

Bend, OR

Overview

Report Status
Final with probable cause
Event Type
Accident
Date
October 8, 2004
Injury Outcomes
No injuries (2 uninjured)
Location
Bend, OR
Aircraft
Maule MT-7-420
Tail Number
N186SB
Injuries
None
Aircraft Damage
Substantial
NTSB Number
SEA05FA004

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.

NTSB Probable Cause

Loss of engine power during takeoff climb for undetermined reasons. Rough terrain was a factor.

Full 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.

Flight

Event TypeAccident
Event Time14:00 PDT
Nearest AirportBend Municipal (0nm)
Runway16
Runway Length5005 ft
Runway Width75 ft
Flight Plan FiledNone
Flight Plan ActivatedNo
Aircraft FireNo
Aircraft ExplosionNo

Aircraft

AircraftMaule MT-7-420
Tail NumberN186SB
Aircraft CategoryAir
DamageSubstantial
Operating RulePart 91
Engines1
Engine TypeTurboprop
Engine DetailsRolls-Royce · 250-B17C · Turboprop · 420
Seats4

People & Injuries

Injury SummaryNo injuries (2 uninjured)
Fatal0
Serious0
Minor0
Uninjured2
Total2
Crew 1Age 54 · Second Class · None
Crew 2None

Conditions

ConditionsVMC
LightDaylight
Wind240° @ 10 kt, gusting 17 kt
Visibility10 sm
CeilingNone
Temperature / Dew Point41 C
Altimeter29.79 inHg
Observation Time21:56
Weather SourceWFAC

Appendix: Source Data