SANDPOINT — The National Transportation Safety Board is mum on the status of the investigation into a plane crash last year that killed aviator and entrepreneur Dr. Pam Riddle Bird and two passengers.

The NTSB probe into the Oct. 8, 2015, crash near Hope has been in the preliminary phase for months. Agency officials decline to release any additional information at this time.

“This is what is available at this time,” NTSB spokesman Keith Holloway said, referring to the preliminary report.

Bird’s Cessna 182P airplane departed from the Bird Aviation Museum & Invention Center in Sagle shortly before 8:30 a.m., according to the NTSB report. The Air Force Rescue Coordination Center reported receiving a emergency locator transmitter ping northeast of Hope at around the same time.

About six hours later, wreckage was discovered by a helicopter near a ridge line on Round Top Mountain.

The airplane collided with numerous treetops before crashing into the mountainside.

“There was a post-crash fire that destroyed the airplane cabin,” the report said.

Also killed in the crash were Bessie “Tookie” Hensley and Don Hensley, 80 and 84, respectively. They were close friends and flying companions of Bird.

The remains of the Hensleys were positively identified through the Spokane County Medical Examiner’s Office. The remains of Bird were unaccounted, although the NTSB report said it’s presumed that she died in the crash.

Family members told investigators that Bird was en route to Gainsville, Fla., with stops planned in Minot, N.D. The flight was originally scheduled for Oct. 7, but was called off due to poor weather conditions. The plane had been fueled to maximum capacity prior to taking off, according to NTSB.

Weather conditions at the time of the crash were a calm wind with an overcast layer about 2,800 above ground level, NTSB said.

Bird was the widow of Dr. Forrest Morton Bird, an aviator and inventor and biomedical engineer. He passed away at age 94, two months before his wife was killed.

The current phase of the NTSB investigation involves probable causes of the crash.