Accident Overview
On July 30, 2016, at 1230 central daylight time, a Ryan Navion B single-engine airplane, registration N5294K, impacted the runway during a forced landing following a loss of engine power during initial climb from Manitowoc County Airport (MTW), Manitowoc, Wisconsin. The private pilot sustained minor injuries; the passenger was not injured. The airplane sustained substantial damage to the left wing. The airplane was registered to Rapier Aviation LLC, Lewes, Delaware, and operated by a private individual as a 14 Code of Federal Regulations Part 91 personal flight. Visual meteorological conditions prevailed, and no flight plan was filed. The local flight was originating at the time of the accident.
Pilot and Flight Details
According to the pilot, the engine run-up, taxi, and takeoff were normal. After establishing a positive rate of climb, the pilot retracted the landing gear. Shortly after gear retraction, the engine lost total power. The pilot attempted to restart the engine without success and performed a forced landing back to the remaining runway surface. The airplane impacted the side of the runway and came to rest upright.
Post-Accident Examination
A Federal Aviation Administration (FAA) inspector examined the airplane and found the left wing and forward fuselage bent. The airplane was recovered to the pilot's hangar for further examination.
On August 8, 2016, the National Transportation Safety Board (NTSB) investigator-in-charge, an FAA inspector, and a representative from Continental Motors, Inc. (CMI) examined the airplane. During the examination, the airplane was resting on its fuselage with the landing gear retracted. The fuel system throttle body and fuel metering unit on the underside of the engine were impact-damaged. Throttle and mixture controls were intact and operational. The engine fuel pump was removed and manually rotated with no anomalies; no fuel was expelled when rotated. The fuel pump drive coupling was intact. Fuel pump hoses contained no fuel. The fuel manifold valve was disassembled and contained a small amount of fuel. Fuel nozzles were clear of contaminants. All six cylinders were examined with a borescope; no damage or unusual wear was found. Engine continuity was verified, and thumb compression was achieved on all cylinders. Both magnetos produced spark when the engine was rotated. During the examination, the fuel selector was observed in the off position. When moved to each tank position (main, left tip, right tip), fuel drained from the airplane.
Pilot Statements and Checklists
The pilot stated that after starting the engine using the electric fuel boost pump on high, he needed to leave the boost pump in the low position to keep the engine running after start. After reaching normal operating temperature, the boost pump could be turned off. The pilot stated he only used the main tank for takeoff and landing. The airplane checklist provided by the pilot indicated the fuel boost pump was used only for starting: "Fuel Pump On High to Fuel Flow Peak" then "Fuel Pump Off". No other uses were indicated.
Further Fuel System Examination
On September 15, 2016, the NTSB and FAA examined the fuel system again. The electric fuel boost pump outlet and inlet lines were removed; no fuel was found in the outlet line, but fuel drained from the inlet line when the fuel selector was moved to each tank position. Forced air applied to fuel lines showed no obstructions. Fuel flowed freely from all tanks to the gascolator, boost pump, and engine fuel pump. Approximately 11 gallons of fuel was drained from the main tanks, and an unmeasured amount from each tip tank. The fuel selector and gascolator were vacuum tested. The gascolator exhibited fuel staining on the top of its casting. The fuel selector showed no leaks. The gascolator leaked air from the top seal, achieving only 20 inches of vacuum (instead of 24) with excessive bleed-down. Disassembly revealed hard, immalleable rubber gaskets.
Engine Fuel Pump Test
On October 26, 2016, at CMI facilities, the engine fuel pump was functionally tested. It had been field overhauled (non-CMI seal). The pump flowed and functioned normally on the test bench. At 2,600 RPM, observed fuel flow was 149.69 PPH (spec 149-150) and observed pressure was 29.84 PSI (spec 33.7-34.3). CMI noted the test confirmed the pump functioned adequately within its designed limitations.
Service Bulletin and Airworthiness Directive
Sierra Hotel Aero, Inc. (SHA) holds the type certificate for the Ryan Navion. In May 2007, SHA issued Service Bulletin (SB) 106A, requiring a one-time inspection of the entire fuel system, including a vacuum test of the gascolator (24 inches of vacuum, bleed-down not exceeding 4 inches per minute) and replacement of gaskets as needed. In April 2008, the FAA issued AD 2008-05-14 to detect and correct fuel system leaks or improperly operating fuel selector valves. The AD allows compliance with SHA SB 106A or the American Navion Society field service bulletin. The aircraft records showed the most recent annual inspection on July 7, 2016. A June 2009 FAA Form 337 documented replacement of the original fuel shut-off valve with an ANS Ltd. fuel valve per American Navion Society instructions as alternate compliance for AD 2008-05-14. No record of compliance with SB 106A was found.