N563JKMooney Airplane M20TN · 2008

On May 10, 2014, about 1305 central daylight time, a Mooney M20TN, N563JK, sustained substantial damage during a forced landing after a loss of engine power while landing at the Stinson Municipal Airport (SSF), San Antonio, Texas. The private pilot received serious injuries. The airplane was registered to and operated by the Chaparral Equipment Leasing LLC under the provisions of the 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed at the time of the accident, and no flight plan was filed. The flight departed SSF about 1250 on a local flight.

The pilot reported that the preflight was normal and the airplane was fueled with 70 gallons of aviation fuel. He did one takeoff and landing on runway 14 without incident. He performed another takeoff from runway 14 and he extended the upwind before turning crosswind due to another airplane landing on runway 09. He erroneously turned final on runway 09, but the SSF tower air traffic controller (ATC) alerted him that he was lined up for runway 09. He corrected course and entered a base leg for runway 14.

The pilot reported that the airspeed dropped below 80 knots, so he pushed the throttle forward 1/2 to 3/4 throttle; however, the engine stopped producing power. He was unable to regain engine power so he made a forced landing into a small clearing along the banks of a river and baseball fields. The pilot did not flare the airplane due to the low airspeed and confined area, so the airplane impacted the terrain hard. The AmSafe airbags installed in the airplane deployed during the ground impact. The pilot crawled out of the cabin and onto the wing where first responders assisted him.

The on-site examination of the airplane wreckage by Federal Aviation Administration inspectors revealed that there appeared to be no apparent reason for the loss of engine power. The airplane wreckage was transported to a storage facility for further examination.

The examination of the airplane wreckage revealed that two of the propeller blades were bent aft, and the third was still straight. The throttle, mixture, and propeller controls were checked for continuity, and the continuity was confirmed from the cockpit to the associated components on the engine. All fuel lines were connected forward of the engine firewall. There was no evidence of a fuel leak forward of the firewall. The fuel manifold on the top of the engine was removed for examination. Fuel was found in the fuel manifold. There was no evidence of obstructions, water contamination, or any malfunction of the fuel manifold. Due to impact damage, the engine was sent to Continental Motors for examination and an engine run.

On September 10, 2014, an examination and engine run were conducted at Continental Motors. The engine exhibited impact damage concentrated at the left side exhaust. The left side exhaust runner, turbo and tail pipe were impact damaged and replaced for the test run. The external surfaces of the engine were undamaged with the exception of the No. 6 cylinder rocker cover, which was replaced for the test run. Both left and right turbo cans were replaced for the test run. A dye penetrant inspection was performed on the crankshaft propeller mount flange; there were no crack signatures evident. The fuel manifold valve was reinstalled for the test run.

Upon installation in the test cell, the fuel pump had a leak at the mixture shaft and was replaced with a slave pump and the engine was run using the slave pump. The original fuel pump was placed on the test bench for a determination of the leak source. On the test bench, no leak was observed from the fuel pump. The pump was reinstalled on the engine and a second test run with all of the original components was completed. On this run there were no leaks present at the fuel pump or mixture shaft area.

The engine experienced a normal start on the first attempt. The engine rpm was advanced in steps for warm-up in preparation for full power operation. The engine throttle was advanced to 1,200 rpm and held for five minutes to stabilize. The engine throttle was advanced to 1,600 rpm and held for five minutes to stabilize. The engine throttle was advanced to 2,450 rpm and held for five minutes to stabilize. The engine throttle was advanced to full open position and held for five minutes to stabilize. The engine throttle was rapidly advanced from idle to full throttle six times where it performed normally without any hesitation or interruption in power. The right magneto had a 240 rpm drop during testing caused by impact damaged ignition leads that were not replaced for the engine test run. Throughout the test phase, the engine accelerated normally without any hesitation or interruption in power, and demonstrated the ability to produce rated horsepower.