The pilot departed on a cross-country flight in his experimental, amateur-built Zenair 601XL, which was equipped with an electronic ignition system.
He did not detect any electrical system anomalies before departure, but, about 14 minutes into the flight, the avionics switched to internal battery power.
The pilot was unable to troubleshoot the electrical system, and about two minutes later the engine experienced a total loss of power.
During the subsequent forced landing to a road near Hempstead, Texas, the airplane’s left wing hit a road sign, resulting in substantial damage.
The pilot conducted a post-accident examination of the airplane and found a loose connection at the generator regulator output. This eventually led to the total loss of electrical power and a subsequent loss of engine power.
Probable cause: A loose output connection from the generator voltage regulator, which resulted in a loss of power to the electronic ignition system, a total loss of engine power, and a subsequent forced landing, during which the airplane impacted a sign pole.
NTSB Identification: CEN16LA167
This April 2016 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.