Amateur-built VELOCITY TXL N916TC accident near Sebastian, Florida

Probable cause

The total loss of engine power due to maintenance personnel’s improper setting of the aneroid adjustment.

NTSB analysis

The commercial pilot stated that before departing on the personal flight, the engine did not start on the first attempt; he primed the engine, and then it started immediately. During the takeoff roll, he noted that he used more of the runway than usual. After rotation, the airplane was not climbing, and then the engine lost total power. He did not have time to restart the engine and performed a forced landing to a field, which resulted in substantial damage. An engine test run and an examination of the fuel pump were performed. The examination revealed that the aneroid adjustment within the fuel pump was set for too rich of a mixture. The rich mixture setting caused the engine to run normally until the manifold pressure went above 36 inches of pressure (in excess of the maximum manifold pressure for which the engine was certified); then it would stumble then lose power. After the aneroid adjustment was set for a leaner mixture, the fuel pump operated normally on the test bench without any anomalies. A review of maintenance work orders revealed that the fuel pump was removed, repaired, and reinstalled about 2 months before the accident. Given this information, it is likely that maintenance personnel set the aneroid adjustment too high at that time, which caused the engine to run with an excessively rich mixture, which resulted in a total loss of engine power on climbout.

Text from the NTSB. Open the NTSB docket for ERA16LA268 for the full record.