Accident Details
On July 19, 2019, at approximately 1210 eastern daylight time, an experimental, amateur-built Vans RV-7A, registration N849GS, was substantially damaged during the initial climb after takeoff from Ocean City Municipal Airport (OXB) in Ocean City, Maryland. The commercial pilot, who owned and operated the aircraft under 14 CFR Part 91, sustained minor injuries. The flight was destined for Manassas Regional Airport (HEF) in Manassas, Virginia, with a filed visual flight rules flight plan. Visual meteorological conditions prevailed at the time.
Pilot Actions
According to the pilot, a preflight inspection and engine run-up revealed no anomalies. After taxiing onto runway 20 and applying full power, about 500 feet above ground level, the engine experienced a partial loss of power. The pilot confirmed the throttle, mixture, and propeller were in the full forward position. He decided to remain in the traffic pattern and land on runway 14, broadcasting his intentions on the UNICOM frequency. During approach, he observed another airplane entering runway 14 for departure and requested the pilot abort the takeoff. The other airplane exited the runway, and the pilot continued his approach. Noting the aircraft was "high and fast" on short final, he chose to land on the runway to avoid landing in the water. The airplane landed "hard" approximately 1,000 feet from the runway end, continued about 150 feet into the grass, nosed over, and came to rest inverted. The rudder was substantially damaged.
Post-Accident Examination
A Federal Aviation Administration inspector examined the engine and found compression on all cylinders, fuel in the fuel lines, and no holes in the crankcase. According to FAA airworthiness records, the aircraft was manufactured in 2004 and equipped with a Superior Air Parts IO-360-B1A3, 180 hp engine. The most recent condition inspection occurred on August 8, 2018, at an airframe time of 431.0 hours, coinciding with the most recent engine overhaul. The Hobbs meter reading at the time of examination was 459.5 hours.
During a subsequent examination with an NTSB investigator, the engine cowling was removed. The governor control arm was found disconnected from the propeller governor, and the control arm locking bolt was missing. Additionally, the secondary control arm/spacer and the spring were not located. The governor control arm pin that slid into the secondary control arm/spacer was not sheared and remained intact. No other engine anomalies were noted. The governor control arm was re-attached (without the missing parts), fuel was plumbed, and the engine started and operated without anomalies. The engine ran smoothly when the throttle was advanced. The propeller lever was operated, and the propeller moved from low pitch, high RPM to high pitch, low RPM multiple times without issue. The propeller control was returned to low pitch, high RPM, and the engine was shut down. The governor control arm was then positioned in the low pitch, high RPM setting to simulate takeoff conditions and disconnected, as initially found. The engine was restarted and the throttle advanced, but the engine RPM would not rise above 1400 RPM at maximum power. After shutdown, the governor control had vibrated and turned to a high pitch, low RPM setting.
Engine Test Findings
A Grand Rapid Technologies Model 4000 Engine Information System installed in the instrument panel was downloaded. The most recent flight data showed that RPM increased to about 2,600 RPM about 8 minutes and 15 seconds into the recording. Then, at approximately 450 feet in the air and 8 minutes and 30 seconds, the tachometer decreased to about 1,500 RPM, maintained for about 1 minute and 12 seconds, then reduced to about 800 RPM, and finally to 0 RPM.