FRISCO - The pilot was killed and two others injured Friday afternoon when a Flight-for-Life helicopter exploded and burst into flames during take-off near Frisco, according to firefighters.

The pilot was identified as 64-year-old Patrick Mahany.

The two injured crew members, a paramedic and a hospital employee, were taken to Denver hospitals. They are expected to survive their injuries, doctors say. Hospital officials say no patient was aboard the helicopter at the time of the crash.

The Flight-for-Life chopper was taking off from St. Anthony Summit Medical Center on a non-medical call when it began to spiral out of control and crash into the ground, witness Curt Weitkunat said.

Weitkunat was at Adventure Park next to the hospital when the crash happened. He said the chopper was trying to gain altitude in windy conditions.

The chopper came down in a parking lot on the west side of the hospital, about 100 meters from the helipad.

Lake Dillon fire crews arrived on scene and found the chopper fully engulfed in flames. Two vehicles parked next to the crash scene were destroyed. No one was inside either vehicle.

Mahany was stuck in the wreckage.

"He was unfortunately stuck in the helicopter and had to be pulled out by our staff," trauma medical director Jodie Taylor said.

The Vietnam veteran had been a pilot with Flight-for-Life since 1987. He received a bronze star and a purple heart during his years of service. He was a loving father, grandfather and a very proud patriot, a Summit County news release said.

"We're deeply saddened that our pilot was killed in the crash. Our hearts go out to the pilot's family," Taylor said.

The Federal Aviation Administration and National Transportation Safety Board have been notified of the crash, and they are sending investigators. They will look into the cause of the crash.

The Astar AS350 B3 helicopter had only been in service in Frisco for less than a year. A bigger, more powerful engine was installed in August. It was considered a state-of-the-art upgrade from the hospital's previous medical helicopter.

9NEWS aviation expert Greg Feith says the number of medical helicopter crashes in the country has been on the rise over the last six years.

"While the helicopter association has been trying to identify cause and causes, they are rare when you look at the grand scheme of how many operations are conducted on a yearly basis," Feith said. "But, anytime you have a tragic accident like this it affects not only families but the entire industry."

(KUSA-TV © 2015 KUSA with The Associated Press)