A plane that slammed into woods near the Salcha River on a Saturday in late May, the second Alaska crash that day to kill two people, reportedly still had engine power when it hit the ground.

The National Transportation Safety Board published an eyewitness account Tuesday of the May 27 crash in a preliminary report. Sam R. Brice, 81, and Howard A. “Buzz” Otis, 61, of Fairbanks and North Pole respectively were killed.

The S-1B2 aircraft, an older model known in aviation circles as an “Arctic Tern,” crashed at about 11 a.m. near Butte Creek about 60 miles east of Fairbanks. According to the NTSB, the men had taken off from an “off-airport landing site near Fairbanks” at about 10 a.m. to look for an overdue boat on the Salcha River.

At about the same time, a Piper PA-30 carrying three people crashed at Glacier Point near Haines in Southeast Alaska, killing its pilot and front-seat passenger. That crash also remains under investigation, with a preliminary report also released Tuesday.

Investigators believe Brice was flying the Arctic Tern, according to Clint Johnson, the NTSB’s Alaska chief. The boat and passengers he and Otis were looking for were later found safe.

“The son of the back seat passenger was overdue, as far as checking in, so what they were doing was just a welfare check,” Johnson said.

The weather just before the 11 a.m. crash that day — reported by Eielson Air Force Base, about 35 miles east of the crash site — included broken clouds at 10,000 feet, 10 statute miles of visibility and calm winds.

Investigators later spoke with a witness to the crash, who reported “strong wind conditions” in the area.

“She observed the airplane circle a remote, unimproved landing site along the Salcha River,” NTSB staff wrote. “While circling, the nose of the airplane suddenly dropped and the airplane descended in a near vertical attitude. She stated that the engine continued to run, and the airplane did not make any unusual sounds, other than an increase in engine (revolutions per minute) during the descent.”

Johnson declined to say whether the NTSB believes the aircraft entered a stall prior to the crash, pending further investigation.

“We can’t specifically say ‘stalled’ at this early stage,” Johnson said. “We’re still very much in the preliminary stages at this point.”

The crashed plane was found nearly vertical, the NTSB report said, “in an area of black spruce trees and tundra-covered terrain.” Johnson said the wreckage was taken to Fairbanks for a full mechanical examination.