The Mitsubishi MU-2
is one of postwar Japan’s most
successful aircraft. It is a high-wing, twin-engine turboprop, and has a
Work on the MU-2, Mitsubishi’s
first postwar aircraft design, began in 1956. Designed as a light twin
turboprop transport suitable for a variety of civil and military roles, the MU-2
first flew on September 14, 1963. This first MU-2, and the three MU-2As built, were
powered by Turbomeca Astazou turboprop.
Civil MU-2s powered
by Garret engines were certified as variants of the MU-2B, using the MU-2B type
followed by a number. For marketing purposes, each variant was given a suffix
letter; the MU-2B-10, for example, was sold as the MU-2D, while the MU-2B-36A
was marketed as the MU-2N.
In 1965, Mitsubishi
established a production facility for North American MU-2 buyers in San Angelo, Texas.
When MU-2 production ended in 1986, aircraft were no longer assembled in Japan. Instead,
the San Angelo Mitsubishi International factory had been building aircraft
using American avionics and airframe components shipped from Mitsubishi’s
facilities in Japan.
Over 750 MU-2 aircraft were sold.
production aircraft, designated MU-2B, were delivered with the Garrett TPE331
engines that remained standard on all later models. 34 MU-2Bs were built, followed
by 18 examples of the similar MU-2D. The Japanese armed forces purchased
four unpressurized MU-2Cs and 16 search and rescue variants designated MU-2E. Featuring
slightly more powerful uprated TPE331 engines, 95 examples of the MU-2F were
The fuselage was
stretched beginning with the MU-2G; these aircraft are covered in later
paragraphs. The MU-2M (only 28 built) is regarded as the toughest and most
desired of all short body MU-2s, especially with a -10 engine conversion. It
had a short fuselage and the same engines as the stretched MU-2J; it was
followed by the even more powerful MU-2K and later the MU-2P, which had newer
four-bladed propellers. The final short-fuselage MU-2s produced were known as
the Solitaire and were fitted with 665 shp (496 kW) Garret TPE331-10-501M
significant change to the airframe came with the stretched MU-2G, first flying
January 10, 1969, which featured a 1.91 m (6 ft 3 in) longer fuselage than
earlier models; 46 were built before being succeeded by the more powerful MU-2J
(108 constructed). The MU-2L (29 built) was a higher-gross-weight variant, followed
by the MU-2N (39 built) with uprated engines and four-bladed propellers. The
final stretched-fuselage MU-2 was named the Marquise, and like the Solitaire
used 715 shp (533 kW) TPE331 engines.
As of 2005, 397 MU-2
aircraft are registered in the United
The Japanese Self-Defense
Forces are the only military operators to have flown the MU-2. The four C-model
aircraft built, in addition to 16 MU-2Ks, entered service with the Japan Ground
Self-Defense Force with the designation LR-1; they were used as liaison and
photo reconnaissance aircraft. 29 MU-2Es were purchased by the Japan Air Self-Defence
Force as search-and-rescue aircraft and designated MU-2S. Additional equipment
consisted of a “thimble” nose radome, increased fuel capacity, bulged
observation windows, and a sliding door for dropping rafts.
MU-2s are currently
flown under government contratct at Tyndall Air Force Base, Florida, where they provide U.S. Air Force
undergraduate Air Battle Manager students with their initial experience
controlling live aircraft. Students must control eight MU-2 missions before
they can progress to controlling high performance aircraft such as F-15s or F-22s.
Like all aircraft, the
safety record of the MU-2 has been examined by government agencies and found to
be acceptable when compared to other aircraft in its class; it was involved in 11
accidents with a total of 12 fatalities in a single 18 month period. Also, as
reported by CNBC, there have been a total of 330 fatalities from MU-2 crashes.
However, there have been years where the MU-2 had no accidents at all. As of
October 2005, the Federal Aviation Administration (FAA) has begun a safety
evaluation of the aircraft and decided that the aircraft has met its
certification requirements – it is safe when operated by properly trained
pilots who operate properly maintained aircraft. The FAA is in the process of
mandating training specific to the MU-2 as it has in the past for other
aircraft. When such mandated training was required outside of the U.S. the MU-2
accident record was vastly improved.
Because the MU-2
offers very high performance at a relatively low cost, some of its operators
lack sufficient training and experience for such an advanced aircraft.
A design feature of
the MU-2 is it’s high cruise speed while having a low landing speed. This is
accomplished by using full-span, double-slotted flaps on the trailing edge of
the wing. These flaps give the MU-2 a wing area comparable to a Beech King Air
in landing configuration while having an wing area comparable to a light jet
while in cruise mode. The full span flaps meant that over-wing spoilers were
employed instead of conventional ailerons. These spoilers are highly effective,
even when the MU-2 wing is stalled. Some fatal accidents have occurred because
normal engine-out procedures for light twin aircraft are not effective when
flying the MU-2. The commonly taught procedure of reducing flap following an
engine failure on take off leads to a critical reduction in lift in the MU-2
due to the highly effective double-slotted flaps. When pilots were taught to
retain take-off flap and to reduce climb rate in the event of an engine failure,
MU-2 accident rates reduced to almost nil.
From an FAA press
The FAA began an aggressive safety
evaluation in July 2005. The evaluation is performing a detailed review of
accidents, incidents, airworthiness directives, service difficulty reports, safety
recommendations and safety reports. It also is examining pilot training
requirements, the history of the aircraft’s commercial operators and possible
engine problems. The goal is to identify the root causes of MU-2 accidents and
incidents and determine what, if any, additional safety actions are needed.
In early 2008 the
FAA issued a Special Federal Air Regulation (SFAR) directed at MU-2B operations.
Pilots flying this aircraft after that date (current MU-2 pilots would have a
year to come into compliance) were required to receive type-specific initial
training, as well as recurrent training. It also required that a fully-functional
autopilot be available for single-pilot operations, and that FAA-approved
checklists and operating manuals be onboard at all times. Also unusual for this
SFAR, pilot experience in other aircraft types cannot be used to comply with MU-2
operational requirements – for instance, the requirement to perform landings
within the preceding 90 calendar days before carrying passengers is altered by
this SFAR to require those landings be made in the MU-2.
There is no
regulatory relationship between the SFAR requirements and a Type Rating, however
both have completion standards located in the practical test standards. The
SFAR requires specific training, currency, and operational requirements. Upon
completion of the training requirements the instructor places an endorsement in
the pilot’s logbook if the instructor feels that the pilot has met the
completions standards outlined in the commercial and instrument PTS. If not, training
continues until the pilot meets the minimum standards. In comparison, an FAA
Type Rating requires the pilot to complete qualified training followed by a
checkride and oral examination by an FAA designated examiner. During a Type
Rating checkride the pilot must perform all portions of the ride to a minimum
of the ATP practical test standards (regardless of the category of airman
certificate held). A Type Rating becomes part of the pilot’s airman certificate.
* Crew: 1 or 2 pilots
* Capacity: 7 passengers
* Length: 10.13 m (33 ft 3 in)
* Wingspan: 11.94 m (39 ft 2 in)
* Height: 3.94 m (12 ft 11 in)
* Wing area: 16.5 m² (178 ft²)
* Empty weight: 2,422 kg (5,340 lb)
* Max takeoff weight: 4,050 kg (8,930 lb)
* Powerplant: 2× Garrett TPE331-25A
turboprops, 430 kW (575 shp each) each
* Maximum speed: 500 km/h (313 mph)
* Range: 1,930 km (1,206 mi)
* Service ceiling: m (ft)
* Rate of climb: 331 m/min (1,086 ft/min)
* Wing loading: 245 kg/m² (50.1 lb/ft²)
* Power/mass: 0.106 kW/kg (0.129 hp/lb)