DUBROVNIK, Croatia - Investigators turned yesterday to unraveling the final minutes of Commerce Secretary Ron Brown's flight and the reason it crashed near this Dalmatian port, killing all 35 people aboard.

Defense Secretary William Perry said initial speculation focused on faulty instrumentation. But many questions remained a day after the jet clipped a barren hill in a raging rainstorm and crashed about two miles short of Dubrovnik's Cilipi Airport.

Why was the plane off course? Why did rescue efforts erroneously focus at first on the waters of the Adriatic Sea? Could Croatian, NATO and U.S. rescuers have reached the site any faster?

Even the number of victims was uncertain until more than 24 hours after the crash. Initial reports from Washington said 33 people were on board, but the State Department listed 35 victims yesterday - all Americans except for one Bosnian and a Croat.

"In travel in this part of the world, and in these conditions, you don't always get a good (passenger) manifest," the U.S. Ambassador to Croatia, Peter Galbraith, told a news conference.

Brown, accompanied by Commerce Department staff members and business executives, left the Bosnian city of Tuzla on Wednesday afternoon for what should have been a short 130-mile flight south to the Croatian coast.

In Tuzla, he had visited U.S. soldiers serving with the Bosnian peace mission, passing out fast-food and sports videos. He was to have visited the Bosnian capital of Sarajevo and the Croatian capital of Zagreb on the trip.

"I am not sure we can overcome the loss of Mr. Brown," said Bosnian Prime Minister Hasan Muratovic, who had been expecting to meet the commerce secretary Thursday in Sarajevo.

Instead, U.S. investigators were arriving to try to determine what caused the T-43, the U.S. military version of a Boeing 737, to crash into the hill, known locally as Sveti Ivan, or Saint John.

The bodies began arriving yesterday at a makeshift morgue set up at the airport. Army Brig. Gen. Michael Canavan and search-and-rescue team members arrived at the crash site before dawn Thursday, and by afternoon there were about 50 members at the site, according to a military spokesman in Germany.

The White House said Canavan identified Brown's body.

Air Force Brig. Gen. Charles H. Coolidge Jr., was scheduled to arrive today to lead another investigation team. Their effort may be hampered by the absence of voice and data recorders, the "black boxes" required on commerical flights. The Air Force said the T-43 did not have them.