Federal investigators say a pilot killed in a crash earlier this month in Sussex County was flying a small experimental plane he had built and was taking on its maiden voyage.

The National Transportation Safety Board said Lester Lydzinski brought his NW-Freedom aircraft to Trinca Airport in Andover on Aug. 6. The 63-year-old Clifton man performed two ground test runs on the turf runway before taking off, but the plane crashed about 30 seconds later after a wing collapsed.

Lydzinski was pronounced dead at the scene.

Officials say he had custom-built the plane's airframe himself but bought the wing from its manufacturer. They also said he had received some flight instruction and had done other solo flights in similar aircraft.

The cause of the crash remains under investigation.