<p>ANCHORAGE, Alaska — A preliminary report from the federal agency investigating the fatal helicopter crash in Alaska that killed five people, including the richest man in the Czech Republic, sheds little light on the cause.</p>
<p>The Tuesday report from the National Transportation Safety Board said the helicopter involved in a heli-ski operation in the Chugach Mountains just north of Anchorage flew multiple legs on March 27, transporting the skiers to several starting points near Knik Glacier.</p>
<p>Data obtained from a handheld GPS unit shows the helicopter started another trip at 6:27 p.m. on a northwest heading, climbing to about 5,900 feet (1,798 meters). Six minutes later, the helicopter began to go over a ridgeline at 6,266 feet (1,910 meters), traveling at about 1 mph (1.61 kph). </p>
<p>“The helicopter maintained a low altitude and groundspeed as it maneuvered over the ridgeline for the next few minutes,” the report says.</p>
<p>The data ended at 6:36 p.m., near the final resting point of the main wreckage. An NTSB investigator surveyed the site the next day by air and said the helicopter hit the mountain about 15-20 feet (4.6-6.1 meters) below the ridgeline before rolling downhill about 900 feet (274.3 meters) in rugged terrain and snowy conditions.</p>
<p>The weather conditions at the nearby Palmer airport were clear with visibility of 10 miles (16 kilometers) and gusts up to 6 mph (9.7 kph) mph.</p>
<p>The Airbus AS350-B3 was operated by Soloy Helicopters in Wasilla. The pilot, Zachary Russell, picked up guides and passengers at a private residence on Wasilla Lake in Wasilla, arranged through a local lodge.</p>
<p>Killed in the crash were billionaire Petr Kellner, 56, and Benjamin Larochaix, 50, both of the Czech Republic; guides Gregory Harms, 52, of Colorado, and Sean McManamy, 38, of Girdwood, Alaska, and Russell, 33, from Anchorage. There was one survivor, David Horvath, 48, of the Czech Republic, who has spoken to federal investigators, the Anchorage Daily News reported.</p>
<p>The helicopter was reported overdue at 8 p.m., and someone searching spotted the wreckage about 90 minutes later. </p>
<p>A final report on the accident, which should include probable cause, is expected within a year.</p>