Amateur-built XL-5 N735D accident near St. Cloud, Florida

Probable cause

The pilot’s failure to properly secure the airplane electrical system’s positive/negative leads to the 24v battery, which resulted in a total loss of electrical and engine power in flight.

NTSB analysis

Shortly after takeoff, when the airplane was at an altitude of 2,000 ft, the engine and electrical system failed simultaneously. The pilot was unable to restart the engine and made a forced landing to an open field, during which the airplane flipped over and sustained substantial damage to the airframe and wings. The airplane wreckage was not located until about 4 hours and 25 minutes after the accident.

The airplane’s engine was equipped with a dual electronic ignition system that required electrical power to operate. The pilot, who was also the builder, had wired the airplane’s electrical system, which was routed through a 24v battery, including the dual electronic ignition system. Postaccident examination revealed that the lugs that connected the positive and negative leads of the airplane’s electrical system to the 24v battery were not crimped properly and that the leads had separated from their lugs, which resulted in the complete loss of electrical and engine power.

The airplane’s 406-MHz emergency locator transmitter (ELT) triggered on impact, and a beacon alert was sent and was received by the Air Force Rescue Coordination Center (AFRCC). The AFRCC called the pilot’s cell phone twice shortly after the accident, but the phone had been displaced during the accident sequence, and the pilot was unable to retrieve it to answer. The pilot’s daughter did not receive a call from the AFRCC even though she was listed as an emergency contact on his ELT registration form.

A review of AFRCC’s response to the accident revealed that the on-duty controller attempted to locate the beacon and initially determined that the airplane was most likely airborne with an active ELT and closed out the incident. However, after several hours had passed, the controller observed the beacon alerts becoming more concentrated and contacted law enforcement, who located the airplane within 45 minutes.

The AFRCC reported that they handled 38 other incidents that day and that the controller was in his first phase of training. However, they indicated that they would use this incident as a training aid for similar cases in the future.

Text from the NTSB. Open the NTSB docket for ERA19LA253 for the full record.