RENO, Nev. - As a state built on gambling, Nevada has been the perfect host for Reno's National Championship Air Races, an event that has promoted the inherent risks in the daredevil sport as part of the thrill for spectators. On the occasions when pilots were killed, boosters were quick to note that no onlookers had ever been hurt. Now the odds have caught up with the races' fans in the worst way, and it has become clear that the rigorous safety measures governing the competition were not enough to protect them. At least eight attendees were killed in Friday's crash of a souped-up P-51 Mustang, along with the pilot. An early focus on what caused stunt pilot Jimmy Leeward, 74, to lose control of his World War II-era plane is whether a critical component of its tail assembly fell off at high speed, sending the Mustang pitching sharply upward and then plunging toward the audience. Some experts say the planes are pushed to such limits - muscled up to exceed 500 mph - that the last-minute inspections of the aircraft at Reno and strict medical and training standards for pilots are scant hedge against disaster. And while safety concerns had stopped such races elsewhere, the 47-year-old event has remained a popular fixture in northern Nevada. "This is an ultra-hazardous event," said Douglas Moss, a former Air Force test pilot who flies for United Airlines and owns a Torrance, Calif., consulting company that specializes in aircraft accident investigations. "Society has to make a decision whether or not the risk to the participants and the risk to the public are worth it." Moss said it appeared from photos of the disabled Mustang that its trim tab broke off from the tail elevator and that Leeward, whose head was no longer visible in the cockpit, lost consciousness when the plane shot nose-up, producing huge gravitational forces. The P-51 had been flying a qualifying heat at Reno-Stead Airport. At last year's races, he recounted, the Galloping Ghost, piloted by the colorful Jimmy Leeward, tore past the competition in its first race and walloped the rest of the field in its second. It was supposed to compete against some of the event's fastest aircraft in its third, but weather got in the way, and the race was canceled. This year, Cross was rooting for the Galloping Ghost to soar past Strega, a repeat event winner. "Now I can't believe that plane almost killed me," he said Saturday. During Friday's race, Strega was in the lead, Cross recalled. Voodoo was second. The Galloping Ghost, or plane No. 177, was next. The planes whipped around a turn and then started blasting down a straightaway at speeds of at least 400 mph. Suddenly, the Galloping Ghost pulled up. Pilots normally pull up when they're in trouble, flying skyward and away from the competition. The higher the altitude, the more options that pilots have for maneuvering, but they usually do it in a much smoother manner than Leeward did, said Gerald DeRego, a retired Air Force pilot, who was sitting in the box seats Friday. The 63-year-old from Penn Valley, Calif., has been coming to the Reno races for the last 15 years, and he knew something was terribly wrong. The Ghost reached its apex and started to roll. To the untrained eye, the roll resembled an aerobatic move called a Split S. But to DeRego, the pilot had lost "elevator authority" and therefore control of the plane. "As soon as he rolled, I knew he was going to hit the crowd somewhere," he said. "Clearly at that point there was no possible way he was going to survive that." DeRego's mind raced. "I could see the airplane coming. He was in a steep dive. I thought, 'Is he going to hit before us, on us or after us?'" He got up to run with the others around him, knocking down chairs in their path. As the nose came down at a steep angle, the plane rotated a bit, enough to likely spare a number of onlookers, he said. But it still slammed into an area about 100 to 150 feet away from DeRego. The shock wave knocked DeRego down. He landed on another spectator. And then, he said, he started crawling, "like a lizard on a hot rock." Optometrist Lent, 72, was watching the race from the bleachers behind the box seats, about 10 feet above the ground. When the plane headed his way, he jumped off the bleachers, twisting an ankle. When he looked up, he said, he saw a big black cloud, and debris was flying into the bleachers "like bullets over your head." Metal littered the tarmac for a quarter-mile, he said, and the box seats "were wiped out." People were lying "all over the place — I mean all over the place." It looked like a bomb had exploded.