It appears that other than the pilot, the injuries and deaths were caused by flying parts of the disintegrating plane not a direct hit.
"It came down directly at us. As I looked down, I saw the spinner, the wings, the canopy just coming right at us. It hit directly in front of us, probably 50 to 75 feet," Ryan Harris, of Round Mountain, Nev., told the AP.
"The next thing I saw was a wall of debris going up in the air. That's what I got splashed with. In the wall of debris noticed there were pieces of flesh."
Besides veteran Hollywood stunt pilot Jimmy Leeward, two spectators were killed and more than 50 were injured amid a horrific scene strewn with smoking debris. There were reports five people were killed, but hospitals confirmed three deaths to the AP on Saturday.
Bloodied bodies spread across the area as people tended to the victims and ambulances rushed to the scene. Video and photos of the crash were captured by several people in the stands, and the horrific images of the wreckage were transmitted around the world within minutes.
John Townes, a Reno pilot, said the plane didn't sound right.
"It wasn't quite vertical. It was at a very slight angle and because of that I think it probably saved a lot of people," he said.
"Normally when you see an air crash, you see recognizable wreckage. There was nothing, just little bits of metal."
Prior to Friday, 19 people had been killed at the National Championship Air Races since their start 1964, organizers said, at least two in P-51s. In 1999, a Mustang disintegrated during a race, scattering debris and damaging a house. In 1994, one of the planes crashed next to a runway after engine failure sprayed the windshield with oil.
Organizers softened two of the curves pilots negotiate after crashes into nearby neighborhoods in 1998 and the one in 1999. In 2007 and 2008, four pilots were killed at the races, prompting local school officials to consider barring student field trips to the event.
Friday's crash was the first time spectators were killed or seriously injured.
Planes at the yearly event fly wingtip-to-wingtip as low as 50 feet off the sagebrush at speeds sometimes surpassing 500 mph. Pilots follow an oval path around pylons, with distances and speeds depending on the class of aircraft.
Mike Houghton, president and CEO of Reno Air Races, said there appeared to be a "problem with the aircraft that caused it to go out of control." He did not elaborate.
The rest of the races, which bring in tens of millions of dollars for the local economy, were canceled.
Tim O'Brien of Grass Valley, Calif., who is chairman of an air show in his hometown and photographed Friday's races, said the P-51 was racing six other planes and was in the process of moving from third place into second when it pitched violently upward, rolled and then headed straight down.
From the photos he took, O'Brien said it looked like a piece of the plane's tail called a "trim tab" had fallen off. He believes that's what caused the plane's sudden climb.
When the aircraft hit the ground, there was a "big explosion but no fire," O'Brien said.
"The propeller (was) spinning very fast, and there was a lot of mass coming down all at once," he said. It was a "very violent impact."
Maureen Higgins, of Alabama, who has been coming to the air races for 16 years, said the pilot was on his third lap when he lost control.
"Obviously he had no control. He was wobbling. He went upside down and then he headed straight for us, straight at the grandstand."
She was sitting about 30 yards away from the crash and watched in horror as the man in front of her started bleeding after debris hit him in the head.
"I saw body parts and gore like you wouldn't believe it. I'm talking an arm, a leg," Higgins said. "The alive people were missing body parts. I am not kidding you. It was gore. Unbelievable gore."
Stephanie Kruse, a spokeswoman for the Regional Emergency Medical Service Authority, told The Associated Press that emergency crews took a total of 56 injury victims to three hospitals. She said they also observed a number of people being transported by private vehicle, and those people were not included in the count.
Leeward, of Ocala, Fla., was a veteran airman and movie stunt pilot who named his P-51 Mustang fighter plane the "Galloping Ghost," Houghton said.
The Mustang that crashed had minor crash almost exactly 40 years ago in Reno after its engine failed. According to two websites that track P-51s that are still flying, it made a belly landing away from the airport. The NTSB report on the Sept. 18, 1970, incident says the engine failed during an air race and it crash landed short of the runway.
P-51 historian Dick Phillips of Burnsville, Minn., said on Saturday that the plane had had several new engines since then as well as a new canopy and other modifications.
Leeward, the owner of the Leeward Air Ranch Racing Team, was a well-known racing pilot. His website says he has flown more than 120 races and served as a stunt pilot for numerous movies, including "Amelia" and "Cloud Dancer."
In an interview with the Ocala (Fla.) Star-Banner last year, he described how he has flown 250 types of planes and has a particular fondness for the P-51, which came into the war relatively late and was used as a long-range bomber escort over Europe. Among the famous pilots of the hot new fighter was WWII double ace Chuck Yeager.
"They're more fun. More speed, more challenge. Speed, speed and more speed," Leeward said.
He talked about racing strategy in an interview Thursday with LiveAirShow TV while standing in front of his plane.
"Right now I think we've calculated out, we're as fast as anybody in the field, or maybe even a little faster," he said. "But uh, to start with, we didn't really want to show our hand until about Saturday or Sunday. We've been playing poker since last Monday. And uh so, it's ready, we're ready to show a couple more cards, so we'll see on Friday what happens, and on Saturday we'll probably go ahead and play our third ace, and on Sunday we'll do our fourth ace."
Houghton described Leeward as a good friend.
"Everybody knows him. It's a tight-knit family. He's been here for a long, long time," Houghton said.
He also said Leeward was a "very qualified, very experienced pilot" who was in good medical condition. He suggested Leeward would have made every effort to avoid casualties on the ground if he knew he was going to crash.
"If it was in Jimmy's power, he would have done everything he possibly could," Houghton said.
The National Championship Air Races draws thousands of people to Reno every September to watch various military and civilian planes race.
The FAA and air race organizers spend months preparing for air races as they develop a plan involving pilot qualification, training and testing along with a layout for the course. The FAA inspects pilots' practice runs and briefs pilots on the route maneuvers and emergency procedures.
Mike French, a private pilot, was his way to the races late Friday when he learned they were canceled after the crash.
"It's unfortunate, tragic in so many ways," said French, 41, of Wellington, Colo.
It would have been his fifth trip and the first for his 8-year-old son, Myles. "He really wanted to go," the dad said.
French said he had the "Galloping Ghost" P-51 image as his computer screensaver.
"It's the weirdest thing," he said. "I just liked the looks of the aircraft."
Associated Press writers contributing to this report include Joshua Freed in Minneapolis, Haven Daley and Ken Ritter in Reno, and Cristina Silva and Oskar Garcia in Las Vegas.