DENVER -- Flightline Aviation, based at Front Range Airport, is one of the largest operators of the Mitsubishi MU-2 airplane in the nation.

In conjunction with its sister company, American Check, its 10 MU-2s fly thousands of hours per year delivering time-sensitive freight across the country.

But as 7NEWS Investigator John Ferrugia reported, two recent fatal crashes of Flightline's MU-2s have caused a serious examination of procedures and major changes in pilot training.

"Many critics call the MU-2 a dangerous airplane," said John Ferrugia. "In fact, about 10 percent of all MU-2s ever built have been involved in fatal crashes, killing more than 300 people worldwide.

Since 1993, Flightline has lost three planes and four pilots.

But company officials, like the MU-2's manufacturer, believe the plane is safe but they demand much more specialized training than the Federal Aviation Administration requires.

Flightline's 10 Mitsubishi MU-2s rack up about 8,000 hours in the sky every year.

For the money, less than $1 million, they can fly faster and carry more than any aircraft of their type. For Flightline, the MU-2s are the backbone of the company.

"We love the Mitsubishi's," said Tony Mulei, the owner of Flightline Aviation. "I don't believe for a minute the Mitsubishi is not a good airplane."

Tony Mulei's MU-2s are loaded five nights per week, hauling banking materials for the federal reserve, medical items and other freight that needs to meet an overnight deadline.

Two of Flightline's MU-2s have crashed in the past 10 months, killing three pilots. Both accidents are under investigation by the National Transportation Safety Board. Another of Flightline's MU-2s crashed in 1993. The pilot was also killed.

"Losing a close friend whether you lose it in an airplane or whether you lose it in another accident, it's a bad thing," said Mulei.

Although Mulei believes the MU-2 is a safe airplane, after the second fatal crash in August, he took drastic action.

"We needed to have someone else," said Mulei. "Experts come in and look at our operation."

So he parked the planes for a week and arranged for competitors to cover Flightline's routes.

"We took the military approach," said Mulei. "We had a stand down."

Mulei brought in an outside consultant to evaluate company procedures and provide enhanced pilot training.

"We needed to do everything above and beyond to really analyze that our operation was being run properly and if there are weak points, we can get them corrected," said Steve Edner, the operations director for Flightline.

Edner is a veteran pilot who has flown the MU-2.

"The Mitsubishi has certain characteristics that are different than other multi-engine aircraft," said Edner. "It doesn't make it a bad airplane, but it certainly does need to have the pilots to be trained specifically on it and on its systems, and its handling characteristics."

Characteristics that can make the plane particularly difficult to fly at slower speeds at low altitude.

Even so, the FAA requires no special training to fly the MU-2.

"If you have a twin engine rating and if you have the money you can go out and buy one of these airplanes, and you can get in it and fly it," said Dr. Don Kennedy, a former University of Colorado professor.

Kennedy has a PhD in aeronautical engineering. He believes the MU-2 is a dangerous airplane.

"It's a recipe for disaster because the airplane is different enough that it really does require special training," said Kennedy.

While Flightline officials don't agree the MU-2 is dangerous, they do agree, pilots need specific training. The FAA calls that a "type rating."

"The way the aircraft is different from other aircraft requires a specific check ride in that make and model of aircraft," said Edner.

So Flightline will now require specific pilot training from an outside firm.

"Each pilot will go to the simulator once a year," said Edner. "If the FAA feels that they want to have the aircraft require a type rating, I would support that."

Both Flightline and the manufacturer, Mitsubishi, say that will help ensure pilot safety. But critics say the issue is not training -- it is the airplane itself -- because it is not only inexperienced pilots who are dying.

"Some of those pilots were very high-time pilots, with the best airline transport rating, which is the highest license a pilot can have," said Kennedy. "Some of them were only transport pilots with many thousands of hours of flying time that could not manage to fly this airplane."

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