Crashes had whittled the expected field from 22 to five, with wreckage from at least a dozen aircraft at one point strewn about the French airfield. But it did not deter between 300,000 to 500,000 from flocking to the Betheny Plain outside Reims for the final event, drawn by the rush of seeing planes turn, twist and race through the air -- and not deterred by the evident risk. That account, from the U.S. Centennial of Flight Commission, was from 1909. More than 100 years later, air shows -- which may include air races -- continue to draw millions. In the process, they generate $110 million annually in the U.S. and Canada alone, according to John Cudahy, president of the International Council of Air Shows. A spike this year in fatalities at such events has raised fresh questions about safety. But it has not detracted from the enthusiasm of many aviation enthusiasts, who still view such races as enthralling competitions. "It's exciting, it's incredibly moving to see these airplanes do what they do and handle the way they are," said aviation analyst Jim Tilmon, himself a former pilot in the U.S. military and with American Airlines, who then compared it to its risks and thrills with auto racing and other sports. Such danger was apparent Friday, when pilot Jimmy Leeward's P-51 aircraft plunged into spectators during a qualifying run at the National Championship Air Races and Air Show outside Reno, Nevada. Nine people -- including the pilot -- were killed, with many more injured. A day later, U.S. Air National Guard Lt. Nate Nueller said an aircraft crashed at a show in Martinsburg, West Virginia, killing the pilot. Cudahy noted there had been at least 13 deaths at U.S. air shows this year -- after none for 2009 and 2010. Mike Cummings, crew chief for the Blue Thunder racing team, watched Leeward's World War II-era plane fly over his head, invert, go into a loop, then slam into the ground. He called the crash "very traumatic (for) the very close-knit" air racing community, be they people such as himself who knew Leeward personally or other enthusiasts worldwide of the sport. Still, he said it would not deter him from continuing to participate. Nor would he hesitate to bring family members, as he has done often in the past, to watch planes race. "(My kids) love the air races," said Cummings. "They realize it's dangerous, that it's not a Sunday afternoon in the park." Air races are sometimes a part of, but distinct from, "air shows," which generally are exhibitions in which pilots demonstrate aerobatics and other aerial moves. What made this tragedy especially bad, according to Sharp, was the fact that the crash killed and injured spectators. "The race pilots know going in what the risks are going in," Sharp said air races typically involved 8 different airplanes standing wing tip, to wing tip right before take off. He said pilots had to have a competitive fire burning inside them, to be involved in this sport. Once you were air-borne, Sharp described it as being very "stressful." "Your head is in a swivel, you're looking for everybody around you. Unlike a race car, air racing is three dimensional. You not only have someone next to you, you could have someone above you or below you," said Sharp. With speeds exceeding 400 miles an hour, Sharp said it took a lot of dedication, commitment, and skill to be an air racer. Sharp's wife Patricia Sharp described air show week as a nerve wracking one for spouses of pilots involved in the races. "During that week you don't eat, you don't sleep, you're scared all the time," said Patricia Sharp. What happened in Reno was their worst nightmare, playing out. Sharp said ground crews spent hours checking out the planes from top to bottom several times before the race, but once the wheels lifted off the ground adrenaline, a competitive spirit, and lady luck were managing the controls. "In this case Jimmy was really pushing the envelope very far. You never know why. Those planes are designed to go 400 miles an hour. He was going close to 500," said Sharp. Officials are blaming the crash on a mechanical problem with the plane, but NTSB officials said it could take months before they can pin-point the exact cause of this plane crash.