Location: Sunriver, Oregon
Accident Number: WPR19FA178
Date & Time: June 22, 2019, 10:40 Local
Registration: N118G
Aircraft: Maule M7-235B
Aircraft Damage: Substantial
Defining Event: Landing gear not configured
Injuries: 1 Fatal, 1 Minor
Flight Conducted Under: Part 91: General aviation - Personal
Analysis
The pilot and passenger departed on a local flight in the amphibious airplane from a paved runway. The passenger described the airplane's rate of climb after takeoff as "slow" and stated that it was apparent that the airplane would not clear the 50-ft-tall trees ahead. A witness described the airplane as "struggling to gain altitude" and noticed a "definite power loss." The pilot performed a forced landing to a river, where the airplane immediately nosed over and began filling with water. The landing gear was found in the extended position and the water rudders were retracted. The landing gear position indicators were operational and also indicated that the landing gear was extended. The position of the landing gear likely resulted in the airplane nosing over upon impact with the water.
Examination of the engine revealed that the muffler baffles had broken at the weld point. The left muffler baffling moved freely inside of the muffler. The right muffler baffling was turned 180° and was obstructing the exhaust outlet. A test run of the engine with the mufflers installed was unsuccessful; however, upon removal of the mufflers, the engine performed with no anomalies. There is no requirement to check the inside of a muffler during annual or 100-hour inspections to ensure that the baffling is intact. It could not be determined as to how long these mufflers had been in this condition. It is likely that the airflow restriction of the separated baffling resulted in a partial loss of engine power and the airplane's subsequent inability to climb after takeoff.
Probable Cause and Findings
The National Transportation Safety Board determines the probable cause(s) of this accident to be:
A partial loss of engine power due to the separation of baffling in both mufflers. Contributing to the accident was the pilot's failure to retract the landing gear on the float-equipped airplane before performing a forced landing to the river.
Findings
Aircraft (general) - Damaged/degraded
Personnel issues Forgotten action/omission - Pilot
Aircraft Wheel/ski/float - Incorrect use/operation
Environmental issues Water - Contributed to outcome
Factual Information
History of Flight
Initial climb Loss of engine power (partial)
Emergency descent Landing gear not configured (Defining event)
Landing Nose over/nose down
On June 22, 2019, about 1040 Pacific daylight time, an amphibious Maule M-7-235B airplane, N118G, was substantially damaged when it was involved in an accident near Sunriver, Oregon. The pilot was fatally injured, and the pilot-rated passenger sustained minor injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.
According to the passenger, the purpose of the flight was to see how the airplane performed with two people onboard. The pilot taxied the airplane to the runway, performed an engine run-up with no anomalies noted, and began the takeoff roll. The passenger stated that the throttle was full forward and the engine did not sound abnormal. He stated that the pilot rotated the airplane about 65 knots with about 1,000 ft of the 5,461-ft-long runway remaining, and the airplane lifted off the runway into ground effect. He recalled that once the airplane climbed out of ground effect, the rate of climb was slow, and it was apparent that they would not clear the 50-ft-tall trees across the river. The pilot maneuvered the airplane to the left, and the airplane touched down on the Deschutes River, nosed over, and began to fill with water. The passenger said that he was unaware that the river was the intended forced landing site until seconds before touchdown.
Two witnesses who saw the takeoff described the airplane as low and struggling to gain altitude. One witness stated that the engine "sounded like the pilot had not throttled up enough or the engine was bogging for some reason." He stated that there was a "definite power loss" but no "engine sputter or misfire." The airplane turned slowly to the left, continued losing altitude, and cleared large trees lining the Deschutes River. The witness then heard a loud pop, saw the splash, and the tail "flip over." Another witness said that the airplane impacted the tops of the trees.
Pilot Information
Certificate: Airline transport; Commercial; Flight instructor
Age: 63,Male
Airplane Rating(s): Single-engine land; Single-engine sea; Multi-engine land
Seat Occupied: Left
Other Aircraft Rating(s): Glider; Helicopter
Restraint Used: 3-point
Instrument Rating(s): Airplane; Helicopter
Second Pilot Present: Yes
Instructor Rating(s): Airplane multi-engine; Airplane single-engine; Glider; Helicopter; Instrument airplane; Instrument helicopter
Toxicology Performed: Yes
Medical Certification: Class 3 With waivers/limitations
Last FAA Medical Exam: March 7, 2019
Occupational Pilot: No
Last Flight Review or Equivalent: June 8, 2008
Flight Time: (Estimated) 7080 hours (Total, all aircraft), 73 hours (Total, this make and model), 15 hours (Last 90 days, all aircraft), 10 hours (Last 30 days, all aircraft)
Pilot-rated passenger Information
Certificate: Commercial
Age: 69,Male
Airplane Rating(s): Single-engine land; Multi-engine land
Seat Occupied: Right
Other Aircraft Rating(s):
Restraint Used: 3-point
Instrument Rating(s): Airplane
Second Pilot Present: Yes
Instructor Rating(s): Airplane multi-engine; Airplane single-engine; Instrument airplane
Toxicology Performed: No
Medical Certification: Class 2 Without waivers/limitations
Last FAA Medical Exam: March 7, 2019
Occupational Pilot: No
Last Flight Review or Equivalent: March 15, 2019
Flight Time: 1600 hours (Total, all aircraft), 155 hours (Total, this make and model), 25 hours (Last 90 days, all aircraft)
Aircraft and Owner/Operator Information
Aircraft Make: Maule
Registration: N118G
Model/Series: M7-235B
Aircraft Category: Airplane
Year of Manufacture: 1996
Amateur Built: No
Airworthiness Certificate: Normal
Serial Number: 23025C
Landing Gear Type: Amphibian
Seats: 4
Date/Type of Last Inspection: December 7, 2018 Annual
Certified Max Gross Wt.:
Time Since Last Inspection:
Engines: 1 Reciprocating
Airframe Total Time: 953.7 Hrs as of last inspection
Engine Manufacturer: Lycoming
ELT:
Engine Model/Series: IO-540-W1A5
Registered Owner:
Rated Power: 235 Horsepower
Operator: On file
Operating Certificate(s) Held: None
The last maintenance performed was dated June 4, 2019, at a tachometer time of 967.7 hours. The exhaust system was sent for repairs during an annual inspection on June 22, 2011, at an airframe total
time of 794.7 hours.
Meteorological Information and Flight Plan
Conditions at Accident Site: Visual (VMC)
Condition of Light: Day
Observation Facility, Elevation: KBDN,3462 ft msl
Distance from Accident Site: 18 Nautical Miles
Observation Time: 02:35 Local
Direction from Accident Site: 38°
Lowest Cloud Condition: Clear
Visibility 10 miles
Lowest Ceiling: None
Visibility (RVR):
Wind Speed/Gusts: 6 knots /
Turbulence Type Forecast/Actual: None / None
Wind Direction: 360°
Turbulence Severity Forecast/Actual: N/A / N/A
Altimeter Setting: 30.12 inches
Hg Temperature/Dew Point: 16°C / 3°C
Precipitation and Obscuration: No Obscuration; No Precipitation
Departure Point: Sunriver, OR (S21)
Type of Flight Plan Filed: None
Destination: Sunriver, OR (S21)
Type of Clearance: None
Departure Time: 10:39 Local
Type of Airspace: Class G
Airport Information
Airport: SUNRIVER S21
Runway Surface Type: Asphalt
Airport Elevation: 4163 ft msl
Runway Surface Condition:
Runway Used: 18
IFR Approach: None
Runway Length/Width: 5461 ft / 75 ft
VFR Approach/Landing: Forced landing
Wreckage and Impact Information
Crew Injuries: 1 Fatal, 1 Minor
Aircraft Damage: Substantial
Passenger Injuries:
Aircraft Fire: None
Ground Injuries: N/A
Aircraft Explosion: None
Total Injuries: 1 Fatal, 1 Minor
Latitude, Longitude: 43.864444,-121.455001(est)
The landing gear was found in the extended position. The water rudders were found in the retracted position. The pontoons (floats) were equipped with four visual landing gear position indicators. Each indicator was operational and indicated that the wheels were extended. Supplement 2 of the Maule Airplane Flight Manual stated, "Do not land on water unless the landing gear is fully retracted."
The engine was examined following recovery from the river. During the first attempt to run the engine, the engine started but would not maintain power. Examination of the mufflers revealed that the baffles had broken off at the weld point. The left muffler baffling moved freely inside of the muffler. The right muffler baffling was turned 180° and obstructed the outlet port.
Both mufflers were removed, and the engine was restarted; the throttle was advanced to about 1,500 rpm. A magneto drop was conducted. A loss of about 100 rpm was noted when the magnetos were
isolated. Power was then advanced to 2,400 rpm with no anomalies noted.
Per the maintenance manual TLC-M-7-235A/B, rev. C, dated April 13, 2016, and Part 43, Appendix D, there is no requirement to check the inside of a muffler during annual or 100-hour inspections to ensure that the baffling is intact. How long the mufflers had been in this condition on the accident engine could not be determined.
Medical and Pathological Information
An autopsy was performed by the Deschutes County Medical Examiner's Office. According to its report, the cause of death was drowning.
A toxicology screen performed by FAA's Forensic Sciences laboratory detected no carboxyhemoglobin or ethanol in blood. Rosuvastatin was detected in blood and liver tissue; rosuvastatin is not impairing.