A fleet of private planes known as the “NASCAR Air Force” has made travel easier for drivers and teams. But Sunday’s crash that killed 10 people flying to a race aboard a Hendrick Motorsports team plane showed such convenience also can involve risks.

“We use planes just like our cars,” said Ricky Rudd, one of several NASCAR Nextel Cup drivers who also are pilots. “We put a lot of hours in the air and have some of the best pilots in the country that fly these things, and some of the best equipment.”

The backbone of the NASCAR air fleet has been two-engine, 12-passenger aircraft like the Beech 200 King Air that crashed into the side of a mountain in thick fog Sunday while trying to land at a small airport near Martinsville Speedway in Virginia.

All 10 people aboard were killed, including team owner Rick Hendrick’s son, Ricky; his brother, John, and John’s two daughters, Jennifer and Kimberly. Also on the plane were the team’s general manager, Jeff Turner, and its chief engine builder, Randy Dorton, as well as Joe Jackson, an executive with DuPont; Scott Lathram, 38, a pilot for NASCAR driver Tony Stewart; and pilots Richard Tracy and Elizabeth Morrison.

For years, nearly everyone traveled back and forth to the races in team vans or private cars, but the proliferation of private planes has changed that.

Nextel Cup teams race 38 weekends each year, including two all-star events. On many of those weekends, the Concord, N.C., Regional Airport — the closest airport for most teams — is buzzing with activity. More than 100 aircraft — helicopters and airplanes — take off and land, ferrying drivers, team owners, crewmen, sponsors and fans to airports near the racetrack.

More aircraft, including a pair of 727 jets owned by Roush Racing, fly in and out of nearby Charlotte Douglas International Airport.

“Actually, it’s not just race weekends,” said Annette Privette, a spokeswoman for the city of Concord. “Our airport has approximately 200 aircraft based there, and about 60 percent of them are NASCAR-related. There’s a lot of flying back and forth to testing and pole nights and driver appearances and races.

“It’s convenient because the teams, obviously, want to spend as much time with their families as possible.”

Nascar driver Mark Martin pulls his jet onto a runway in this 1998 photo. So many drivers have private planes that they're often called the NASCAR

Petty Enterprises driver Jeff Green sees private-plane travel as more than just a convenience.

“Taking the chance on being delayed in an airport just won’t work,” Green said. “You have to be there Friday morning for practice or you miss practice. Miss practice, and they don’t let you attempt to qualify.

“It’s more than just drivers. The crews, everybody has to use private planes. We’re not talking about convenience, we’re talking about necessity. To be able to test and to be able to get to the tracks where you need to be — on top of doing the things you need to do for your sponsors and your team — you just don’t have much choice.”

Mark Martin, another driver who also is a pilot, lost his father, stepmother and half sister in 1998 when a private plane his father was piloting crashed in Nevada. But Martin said he had no qualms about continuing to use his plane.

“I suppose we’ve been pretty lucky in a way,” Martin said in an interview last year. “But everybody knows that flying is still safer than driving in your personal car. And we really have no choice. We have to fly to get our jobs done.”

With the escalating use of helicopters — for short hauls — and private planes, NASCAR’s Air Force has a very good safety record.

Driver Alan Kulwicki and three others were killed in the crash of a private plane in 1993 while flying to a race in Bristol, Tenn. Later that same year, Davey Allison died in the crash of his helicopter as he tried to land at Talladega.

There had been no aircraft-related fatalities in NASCAR since, but that doesn’t mean there haven’t been accidents.

In one three-week period in November 2003, Martin’s plane blew two tires taking off from a Goodyear, Ariz., airport after racing at Phoenix, a plane carry Petty crewmen also blew a tire on takeoff after a test earlier in Phoenix, and driver Tony Stewart’s plane hit a deer while landing to refuel at a rural Texas airport on the way to the Phoenix race. There were no injuries.

There is, however, a substitute for the small planes.

Martin’s team owner, Jack Roush, bought his 727s four years ago after starting to feel less comfortable about having up to 16 small planes in the air each race weekend.

“I have five teams, and we’d have five small planes going to the track on Thursday night or Friday and five more on Sunday morning,” Roush said. “There’s tremendous congestion at these airports, although I think the FAA does a great job on regulating the air traffic associated with our events. Still, I didn’t feel like I wanted to continue to have the responsibility for 16 airplanes, all the maintenance and pilot training.”