Federal investigators from The National Transportation Board have just filed the first report on a heli-skiing accident last month in Alaska that killed 5 people including billionaire Petr Kellner, the richest man in the Czech Republic.

According to the NTSB report the pilot was was maneuvering over a ridge in the Chugach Mountains for several minutes before impact. A data track from the helicopter shows the group flying out of Tordrillo Mountain Lodge in an Airbus AS350B3 had already taken off and landed in the mountains near the glacier several times, and may have been looking for a spot to set down. The helicopter impacted 15-20 feet below the top of the ridge line. The debris field extended 900 feet below the top of the ridge line.

The NTSB preliminary report does not draw any conclusions on what may have caused the March 27th accident. Their final report is expected to take months as investigators conduct interviews, review data recorders and comb the wreckage site. Our deepest condolences to the family and friends of the victims.