A new report from the National Transportation Safety Board begins to explain the final moments of a medevac plane that crashed last month, killing three crew members on board.

The preliminary accident report states the Piper PA-31-350 airplane flew into the side of a mountain about 15 miles west of Cooper Landing then caught fire after impact.

The chartered flight operated by Security Aviation was en route to Seward from Anchorage on Nov. 29 to pick up a patient at the request of Medevac Alaska, an air ambulance company.

However, Medevac Alaska was not the first company contacted by Providence Seward Medical Center for the flight. Two other air ambulance services declined the flight due to weather conditions.

The report reads:

"The first company contacted was Guardian Flight, who declined the flight at [4:24 p.m.] due to limited daylight hours. The second company, LifeMed Alaska, declined the flight at [4:37 p.m.] due to weather. The third and final company contacted for the fight was Medevac Alaska. Their dispatch officer was not notified of the previous declined flight requests and forwarded the request to Security Aviation, who is their sole air charter provider."

At 5:31 p.m. Security Aviation accepted and flight SVX36 was staffed by pilot Glen Morthorpe and with two Medevac Alaska crew members, Maddox Burts and Robert Cartner.

The three people on board the fatal Security Aviation crash were pilot Glen Morthorpe and Medevac Alaska crew members Robert Cartner and Maddox Burts. (Photos courtesy: Security Aviation, Medevac Alaska)

The report says the plane flew toward the Sterling Highway at 3,000 feet before descending to 2,200 feet before entering the valley to Cooper Landing. The last data recorded showed the plane near the west end of Jean Lake.

Witnesses said they saw the plane flying above the Sterling Highway that night. One person described how the plane circled before it entered the valley.

"He observed the wings rocking back and forth and while he was looking elsewhere, he heard an explosion and observed a large fire on the mountainside. Another witness reported seeing the airplane flying low and explode when it impacted the mountain," the report reads.

Security Aviation's chief pilot would later report the plane was overdue. A search team found the burning wreckage but was unable to access the crash site due to high winds in the area. 

Two days later, Alaska State Troopers and the Alaska Mountain Rescue Group reached the plane in a "steep, heavily tree-covered" area 1,425 feet above the southeast end of Jean Lake.

"The airplane was highly fragmented and burned, however all the major airplane components were accounted for," the document states.

Parts of the airplane recovered from the site will be examined further.

The route from Anchorage to Seward is about 75 nautical miles (86 land miles) southeast across the Kenai Peninsula and Kenai Mountains to the coastal town of Seward. The closest official weather observation site was the Soldotna Airport, 30 nautical miles (34 land miles) west of the accident site. Weather conditions included in the report state the 6:56 p.m. observation included wind out of the west-southwest at 3 knots and a visibility of 10 miles.

Skies at that time were partly cloudy with a temperature of 36 degrees. The sun had already set that day at 3:54 p.m. and witnesses report in the area of Cooper Landing during the time of the crash it was dark with gusty winds.

Seward's special weather observation for 4:23 p.m. included calm winds, 3 miles visibility with light rain/mist, with cloudy skies at the time. At 4:53 p.m. weather conditions at the time were light winds out of the northeast, with a visibility of 8 miles in light rain/mist and cloudy skies.

Just an hour later conditions showed that winds out shifted out of the southeast at 3 knots, with visibility reduced to 5 miles in light rain and cloudy skies remaining.

KTVA meteorologist Aaron Morrison contributed to this report.

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