A U.S. congressman is raising a fundamental question about the Mitsubishi MU-2. Rep. Tom Tancredo (R-Colo.) is convinced that the airplane has a “shockingly high accident rate” and appears to be concerned that no one in the government took his advice last year that the airplane be grounded.

In a September 8 press release he publicized a letter he sent to President Bush calling for replacement of FAA Administrator Marion Blakey and NTSB chairman Mark Rosenker. “Because [they] have consistently failed to take appropriate action on this issue,” the release stated, “despite repeated warnings about the aircraft’s suitability for use, I believe the public would be well served if they were replaced by administrators willing to act swiftly and deliberately on this matter.”

The first question Tancredo raises is: does the MU-2 have a shockingly high accident rate? To answer that question, it is necessary to determine what constitutes a shockingly high accident rate.

Mitsubishi Heavy Industries America, the division responsible for MU-2 product support, recently contracted with accident analyst Robert E. Breiling Associates to prepare a report titled “World and U.S. Business Turboprop Aircraft Accident Analysis.” The August report reviews business aviation and air carrier turboprop accidents that occurred between 2001 and 2005 and involved Part 91, 135 and non-scheduled charter air carrier operations.

Breiling’s report considers the total number of accidents and the accident rates (accidents per 100,000 flight hours). Flight hours used to develop the rate numbers were derived from airframe manufacturer utilization reports or from surveys conducted by GAMA, NATA and NBAA. In cases where no utilization information was available for a particular aircraft type, the report used annual utilization numbers from similar airplanes, Breiling explained.

According to the information from between 2001 and 2005, the MU-2 is not the turboprop with the highest fatal accident rate. Discounting airplanes with tiny fleet sizes such as the HS.748 or unusual uses (Lockheed L-100/130), there are plenty of airplanes with higher fatal accident rates and quite a few with lower fatal accident rates.

Breiling also compared the MU-2 fatal accident rate with that of all U.S.-registered turboprops over a five-year period (2000 to 2004). The MU-2’s rate of 1.68 is higher than the 1.08 rate for the entire turboprop fleet. The fleet rate is based on FAA survey-derived flight hours, while Mitsubishi provided the MU-2 hours. These numbers may not be comparable because, according to Breiling, “Hours reported by the manufacturers have been consistently between 15 and 18 percent higher than the hours reported by the FAA in its ‘Annual General Aviation Activity Survey,’ which seriously affects accident rates in the FAA’s annual survey.”

The MU-2 ranks higher than most business jets in fatal accident rates when looking at accidents between 1964 and 2000, according to the Breiling report. With a fatal accident rate of 1.89, the Learjet 23 is the only jet that has a higher fatal accident rate than the MU-2’s 1.88. The next closest is the Israel Aircraft Industries 1121. With the exception of the Learjet 24/25/28/29 (at 1.04), all the other jets had rates below 1.00. “A higher percentage of the Lear 23/24/25-series accidents,” Breiling wrote, “involved pilots who lacked simulator training.”

Simulator Training
The absence of simulator-based professional training ranks high on the list of reasons for the MU-2’s accident rate, according to Breiling’s report. The lower accident rate of MU-2s operated outside the U.S., Breiling explained, “is largely due to the fact that a number of non-U.S. countries require an ‘aircraft specific’ rating similar to a type rating in the MU-2.

“Simulator training initiated in the 1970s for airlines and in the 1980s for business turbine fleets reduced accidents by up to two-thirds and eliminated the practice of engine-out maneuvers in aircraft.” FlightSafety International used to operate MU-2 simulators at its Houston Learning Center, and SimCom now offers MU-2 simulator training at its Orlando, Fla. facility.

Breiling found that no pilot in any accident that occurred between 1996 and last year “had successfully completed MU-2 aircraft simulator training. All pilots received either ‘in-house’ (company-conducted) training or retained the services of an independent outside instructor that did not have provisions for simulator training and was not necessarily approved by [Mitsubishi].”

Elsewhere in the report, Breiling also stated that most charter operations provide in-house training. The MU-2 “is used extensively in charter/air-taxi/cargo carriage where exposure is considerably higher than average. Operation is largely at night, [and] aircraft are frequently flown by one pilot who has accepted employment with the charter operators to build flight time to later move to air carrier operations.”

Another factor, he noted, is that “as the purchase price of the MU-2 has decreased, individuals who have insufficient experience overall are purchasing this high-performance aircraft rather than a piston-powered twin. To keep costs low, many of these operators are conducting the minimum amount of aircraft initial and recurrent training and maintenance.”

Between 2001 and 2005, there were 21 MU-2 accidents, nine of them resulting in fatalities. Of those accidents, eight (four fatal) involved personal/business pilots. Thirteen accidents (eight fatal) involved commercial operators. There were no accidents during this period involving professional (corporate) pilots.

During that period, there were 309 MU-2s in the active U.S. fleet, with 24 percent (74) flying commercially, 66 percent (204) owner-flown and 10 percent (31) corporate-operated. The commercially operated MU-2 fleet experienced the highest percentage of accidents during that period.

The FAA completed a Flight Standards Board evaluation of the MU-2. The result of the evaluation is an NPRM for stringent new training requirements, both for initial and recurrent training for all MU-2 pilots.

Mitsubishi received FAA approval of its MU-2 training program in July and commercial training providers have been using the program since. The Notice of Proposed Rulemaking to make the training program mandatory was published on September 28 with a comment deadline of just 30 days. After the required comment period, the new rule should become law, but it is too soon to say how long that might take.

FAA regulations do not require that multiengine-rated pilots transitioning from a piston twin to a turboprop receive any turboprop-specific training, unless the airplane weighs more than 12,500 pounds.

To return to the questions Tancredo raises: is the MU-2’s accident rate shockingly high? Should the airplane be grounded?

Many people die in aircraft accidents not involving MU-2s. Between 2001 and 2005, seven of the types listed in the Breiling report world fleet statistics had accidents that killed the same number or more people as the MU-2.

Three times as many people died in Cessna Caravan accidents. (That type has more than three times as many airplanes operating and flies more than three times as many hours per year.) The next highest number of fatalities during that period involved the King Air 200, but it fields a much larger fleet and flies more hours than the MU-2.

Neither Tancredo nor his office responded to multiple requests for information about why the congressman is targeting the MU-2 and whether he feels that other aircraft types with standout accident records ought to be grounded. Two of the more recent MU-2 fatal accidents involved family members of Tancredo’s constituents.