NEW IPSWICH, N.H. (AP) – The pilot of a home-assembled helicopter that crashed into water Thursday was in critical condition Friday at a Massachusetts hospital, police said.

No one saw the crash, but police said pilot James Starbuck, 60, a New Ipswich resident, apparently was underwater for about five minutes.

Starbuck was taken to Monadnock Community Hospital in Peterborough before being transferred to the UMass Memorial Medical Center in Worcester, where he was in critical condition Friday.

Federal investigators helped identify the helicopter as a Mosquito XEL made from a kit.

Based on that, the crash did not require further federal investigation.

The single-seat chopper crashed in about six feet of water. Witnesses said Starbuck had been practicing takeoffs and landings when the chopper flipped over and sank in what initially was described as a pond.

“I heard, like, the splash of something – that was it – and I knew right away that the guy, he was either in the water or something happened,” witness Nathan Sikkila told WMUR-TV. “So we turned around and went down to look, and we found the helicopter upside down.”

Sikkila helped rescue Starbuck.

A friend, Roland Coats, said Starbuck had been working on the chopper for some time.

“He’s been just hovering a little bit with it,” Coats said. “But it looks like he tried to take it out a little bit further than he has in the past.”

AP-ES-07-20-07 1234EDT