Mitsubishi MU-2

Solitaire

In 1959, MHI started on a utility/ executive aircraft aimed at the emerging business aviation market. It was announced in April 1962 that Mitsubishi were to build one flying prototype and a structure test airframe of a shoulder-wing twin-turboprop utility aircraft under the XMU-2 designation. A mock-up had been built and the aircraft is described as being similar in appearance to the Aero Commander, but smaller, with a circular-section fuselage. The engines were to be French or Canadian turboprops of 500 hp each.

On 14 September 1963 the first of four prototypes was flown, a cantilever high-wing monoplane with a pressurised fuselage, retractable tricycle landing gear and two wing-mounted turboprop engines. The first MU-2 prototype flew powered by French Turbomeca Astazou engines. The fourth airplane to be tested was fitted with an early version of the Garrett AiResearch TPE 331, and all subsequent MU-2s have been powered by TPE 331 turboprops. By 1965, the short body MU-2B was certified by the FAA for use in the U.S. and sales to American firms began. To achieve roll control when the wing required full span flaps, Mitsubishi developed a small spoiler that resides at about the two-thirds chord position and extends along most of the wing's span.

Since 1965, MHI has improved the MU-2 as the technology of general aviation aircraft advanced, but with the exception of powerplants and systems, very few changes in the airframe were necessary. As more power was added, a speed increase of 15 percent and a gross weight increase of 30 percent was achieved. The first significant changes to the MU-2 appeared in 1968 when the aircraft was fitted with larger tip tanks and powered by 705 eshp TPE 331s.

Initial production versions were the MU-2A with Turbomeca Astazou turboprops, MU-2B with Garrett TPE331 turboprops and a similar MU-2D, an unpressurised multi-role MU-2C for the Japanese Ground Self-Defence Force, a search-and-rescue MU-2E, and the MU-2F with uprated TPE331 engines.

Models B and D were powered by 605 shp and seated 7-9 passengers. The Model F represented a boost in power to 705 shp.

Certification of the MU-2B-26A is FAA A10SW, and the MU-2B-30 JCAB 25.

The first stretched (by 1.88 m) MU-2 was the G model, which was based on the MU-2F and introduced in 1969. The Model G featured increased seating capacity for up to 11 people, and the powerplant of the MU-2F.

In 1971, the eshp of the AiResearch turbines was increased to 724 for use on the long bodied MU-2J and the short bodied MU-2K, which were introduced in mid-1972. Both utilizing 724-shp turboprops and offering seating arrangements that corresponded to Models F and G, respectively.

Subsequent versions have included the MU-2J with more powerful engines, and MU-2K combining MU-2F fuselage and MU-2J powerplant.

Mitsubishi MU-2J N113SD

The MU-2L and M models (variants of the MU-2J and MU-2K respectively), with their increased gross weights and added soundproofing, were announced at NBAA in September, 1974. Fitted with full span, high lift flaps and two Garrett AiResearch TPE 331-6-251M engines, rated at 776 equivalent shaft horsepower on the L model and at 724 eshp on the M model. Thus, both Mitsubishis have power loadings of 8.1 pounds of aircraft per horsepower for the MU-2L and 7.9 lbs/hp for the MU-2M. The L and M model use AiResearch cabin pressurization systems with Hamilton Standard air conditioning utilizing bleed air from the engines. The MU-2L, nine feet longer inside than the MU-2M, providing accommodations for a pilot and from seven to ten passengers. The MU-2L uses 178 square feet of wing area and a NACA 64A415 airfoil to produce a high speed wing that carries a load of 65 pounds per square foot.

The MU-2L and MU-2M were discontinued in 1976 and replaced by the MU-2N and MU-2P with Garrett TPE331-5-252M engines. The 90 inch, three-blade propellers that were standard on MU-2Ls and Ms are replaced on the latest models by 98 inch, four-blade props that turn at 1,591 rpm on take off, only 80 percent of the revolutions previously used. Because of the slower turning propellers, the propeller tip speeds are reduced about 100 feet per second in spite of the increased prop diameter needed to produce the same thrust horsepower available on older MU-2s. The result is a dramatic 25 per-cent reduction in perceived noise levels within the cabin and no loss in performance.

The new aircraft are designated the MU-2N and the MU-2P (the latter model has the shorter fuselage). In addition to larger, slower turning propellers, both models are equipped with the Woodward fuel control units; a move which will mark a return to the fuel control units utilized by Mitsubishi in their early MU-2 models. Purchasers of L or M model Mitsubishis have the option to upgrade their new aircraft to the standards of the MU-2N or MU-2P, respectively, should they wish to have the slow turning engines with the Woodward fuel controllers.

The MU-21P 98-inch four-blade propellers have been slowed 20 percent, to 1,591 rpm for takeoff and 1,561 during cruise. According to the factory, that reduces the interior noise level by 25 percent. A vertical fin now sprouts from the top of each tip tank, to help improve low-speed roll stability, and there's a new taxi light in the nose of each tank. A new windshield can be seen in the cockpit; the new glass creates less distortion.

Spoilers replace the ailerons to good advantage; they remain equally effective at all airspeeds, eliminate adverse aileron yaw and, most significantly, permit space for almost full-span double-slotted Fowler flaps. When fully extended, the flaps increase wing area by 24 percent and reduce stalling speed by 24 knots. Taking off at Vmc (93 knots) allows the airplane to clear a 50-foot obstacle in 1,800 feet at gross on a standard day. In fact, the airplane's single-engine rate of climb is 760 fpm, at a typical weight of 9,250 pounds. The MU-2P is a short-coupled machine, and this shows up during takeoff and landing. Bluntly stated, the MU-2P is lacking in pitch control power, and some piloting effort is required to compensate for that shortcoming. The problem is apparently limited to the short-fuselage version; the longer-body MU-2s, including the new four-blade MU-2N, do not display any pitch difficulties. When leaving or entering ground effect during takeoff or landing, the low-mounted tailplane is affected more than the high wings because of the particular relationship between them, and this produces a forward pitching force. The MU-2P, with its short fuselage and narrow center of gravity, demonstrates the effects of this nose-down load more vividly than do most airplanes.

An ar-rangement was struck with Mooney Aircraft for assembly and marketing of the MU-2, and that lasted until it was dissolved in 1970 after Mooney had been purchased by Butler Aviation. But as early as 1967, Mitsubishi Aircraft International, Inc. had been formed, and by 1970, MAI was in a position to take over both the assembly of MU-2s in San Angelo and marketing of the product. Mitsubishi Aircraft International, Inc., a U.S. corporation based in San Angelo, Texas was responsible for assembling MU-2s and marketing them in the US and throughout the world.

The MU-2S is the Japan Air Self-Defence Force patrol aircraft, which resembles the civilian aircraft but has a shorter fuselage and bulbous radar nose.

The MU-2N and MU-2P evolved into the Solitaire (standard fuselage) and Marquise (stretched fuselage), respectively. Both airplanes have 1,000 -horsepower engines, wet-wing fuel tanks that hold an additional 40 gallons and are certificated to 31,000 feet. The MU-2 designation will be dropped. The Solitaire succeeded the MU-2P, and the Marquise the larger, slower MU-2N.

The Solitaire is powered by two Garrett TPE331-10-501M turboprops producing 727 shp at maximum continuous power or 689 shp at recommended cruise power of 96% RPM. Each engine turns a Hartzell 98-inch four-blade prop and provides a 475-fpm single-engine rate of climb when loaded to full gross. With a cabin pressurization differential of 6.0 psi, a sea-level cabin can be maintained up to 14,000. The Marquise, which is 6 feet 2 inches longer, is powered by two turboprops, each producing 778- shp for takeoff or maximum continuous operation and 738 shp at recommended cruise power. Single-engine rate-of-climb is 410 fpm at full gross, and cabin pressurization differential is the same as the Solitaire. The long-fuselage Marquise accommodates a crew of two plus seven to nine passengers; and the Solitaire, seating a crew of two plus six or seven passengers.

Sales of the Mitsubishi MU-2 passed the 700 mark in July 1981 when the total reached 702. Since the twin-turboprop business transport was introduced in 1966, 518 were sold in the USA, 20 in Canada, 58 in Latin America, 36 in Europe, nine in Africa, eight in Australia, one each in the Middle East and Asia and 51 in Japan. The last 100 aircraft were sold since September 1979.

When production ended at the end of 1983, 831 MU-2s of all versions had been built, including 73 military versions.

MU-2 prototype

Engines: 2 x Astazou II turbo-prop, 415kW

Wingspan: 10.3 m / 33 ft 10 in

Length: 10.1 m / 33 ft 2 in

Height: 4.0 m / 13 ft 1 in

Wing area: 16.6 sq.m / 178.68 sq ft

Max take-off weight: 3600 kg / 7937 lb

Empty weight: 2072 kg / 4568 lb

Max. speed: 525 km/h / 326 mph

Cruise speed: 523 km/h / 325 mph

Ceiling: 11000 m / 36100 ft

Range w/max.fuel: 2830 km / 1759 miles

Crew: 1-2

Passengers: 5-13

**MU-2B-26A **

Engines: 2 x Garrett TPE-331-252M, 605 shp.

Seats: 7/9.

**MU-2B-60 Marquise **

Engines: 2 x Garrett TPE-331-10-501M, 715 shp.

Props: Hartzell 4-blade, 98-in.

Seats: 9/11.

Length: 39.4 ft.

Height: 13.7 ft.

Wingspan: 39.2 ft.

Wing area: 178 sq.ft.

Wing aspect ratio: 7.7.

Maximum ramp weight: 11,625 lbs.

Maximum takeoff weight: 11,575 lbs.

Standard empty weight: 7650 lbs.

Maximum useful load: 3975 lbs.

Zero-fuel weight: 9950 lbs.

Maximum landing weight: 11,025 lbs.

Wing loading: 65 lbs/sq.ft.

Power loading: 8.1 lbs/hp.

Maximum usable fuel: 2700 lbs.

Best rate of climb: 2100 fpm

Service ceiling: 29,400 ft.

Max pressurisation differential: 6 psi.

8000 ft cabin alt @: 27,300 ft.

Maximum single-engine rate of climb: 410 fpm @ 152 kts.

Single-engine climb gradient: 158 ft/nm.

Single-engine ceiling: 14,800 ft.

Maximum speed: 309 kts.

Normal cruise @ 20,000ft: 295 kts.

Fuel flow @ normal cruise: 592 pph.

Endurance at normal cruise: 4.1 hrs:

Stalling speed clean: 100 kts.

Stalling speed gear/flaps down: 81 kts.

Turbulent-air penetration speed: 191 kts.

Takeoff distance (50') 2,170 ft

Landing distance (50') 2,200 ft

**MU-2B-400 Solitaire **

Engines: 2 x Garrett TPE-331-10-501M, 665 shp

Props: Hartzell 4-blade, 98-in

Seats: 7/9

Length: 33.3 ft

Height: 12.9 ft

Wingspan: 39.2 ft

Wing area: 178 sq.ft

Wing aspect ratio: 7.7

Maximum ramp weight: 10,520 lbs

Maximum takeoff weight: 10,470 lbs

Standard empty weight: 7010 lbs

Maximum useful load: 3510 lbs

Zero-fuel weight: 9700 lbs

Maximum landing weight: 9950 lbs

Wing loading: 59 lbs/sq.ft

Power loading: 7.8 lbs/hp

Maximum usable fuel: 2700 lbs

Best rate of climb: 2250 fpm

Service ceiling: 31,000 ft

Max pressurisation differential: 6 psi.

8000 ft cabin alt @: 27,300 ft

Maximum single-engine rate of climb: 475 fpm @ 150 kts

Single-engine climb gradient: 190 ft/nm

Single-engine ceiling: 16,900 ft

Maximum speed: 321 kts

Normal cruise @ 25,000ft: 309 kts

Fuel flow @ normal cruise: 526 pph

Endurance at normal cruise: 4.6 hrs

Stalling speed clean: 104 kts

Stalling speed gear/flaps down: 78 kts

Turbulent-air penetration speed: 182 kts

**MU-2J **

**MU-2L **

Engines: 2 x AiResearch TPE-331-6-251M, 776 eshp

Max cruise pwr: 767 eshp

Prop: Hartzell 90in Constant speed, full feather with reverse pitch

Span: 39 ft. 2 in

Overall length: 39 ft. 5 in

Overall height: 13 ft. 8 in

Wing area: 178 sq. ft

Cabin length: 19 ft. 8 in

Cabin width: 4 ft. 11 in

Cabin height: 4 ft. 3.2 in

Baggage compartment: 44 cu. Ft

Seats: 8-11

Empty weight: 6,380 lbs

Standard equipped weight: 7,570 lbs

Max takeoff weight: 11,575 lbs

Max ramp weight: 11,625 lbs

Useful load (with std equip): 4,055 lbs

Payload with full fuel: 1,603 lbs

Usable fuel capacity: 366 US gal

Max cruise: 340 mph

Rate of climb at sea (10,350 lbs): 2,630 fpm

ROC SE: 675 fpm

Service ceiling (10,350 lbs): 29,600 ft

Service ceiling (10,350 lbs) SE: 15,450 ft

Stall speed: 88-115 mph

Max range 30-min res: 1450 miles

Takeoff distance over 50 ft. at 11,575 lbs: 2170 ft

Ldg dist from 50 ft. at 9,473 lbs: 1880 ft

Pressurization: 6.0 psi

Cabin alt @ 24,000 ft: 6200 ft

**MU-2M **

Engines: 2 x AiResearch TPE-331-6-251M, 724 eshp

Max cruise pwr: 715 eshp

Prop: Hartzell 90in Constant speed, full feather with reverse pitch

Span: 39 ft. 2 in

Overall length: 33 ft. 3 in

Overall height: 12 ft. 11 in

Wing area: 178 sq. ft

Cabin length: 11 ft

Cabin width: 4 ft. 11 in

Cabin height: 4 ft. 3.2 in

Baggage compartment: 43 cu. Ft

Seats: 7-9

Empty weight: 5,920 lbs

Standard equipped weight: 6,864 lbs

Max takeoff weight: 10,470 lbs

Max ramp weight: 10,520 lbs

Useful load (with std equip): 3,656 lbs

Payload with full fuel: 1,204 lbs

Usable fuel capacity: 366 US gal

Max cruise: 365 mph

Rate of climb at sea (9,250 lbs): 2,840 fpm

ROC SE: 760 fpm

Service ceiling (9,250 lbs): 32,200 ft

Service ceiling (9,250 lbs) SE: 18,000 ft

Stall speed: 84-112 mph

Max range 30-min res: 1680 miles

Takeoff distance over 50 ft. at 10,470 lbs: 1800 ft

Ldg dist from 50 ft. at 8338 lbs: 1600 ft

Pressurization: 6.0 psi. Cabin alt @ 24,000 ft: 6200 ft

Wing loading: 58.8 lb/sq.ft

**MU-2N **

Engines: 2 x Garrett TPE 331-6-251M, 715 hp

Seats: 11

Wing loading: 65 lb/sq.ft

Pwr loading: 8.1 lb/hp

Gross wt: 11,625 lb

Empty wt: 7570 lb

Equipped useful load: 4040 lb

Payload max fuel: 1601 lb

Range max fuel/cruise: 772 nm/2.6 hr

Range max fuel / range: 1112 nm/ 4.5 hr

Service ceiling: 25,000 ft

Max cruise: 291 kt

Max range cruise: 250 kt

Vmc: 99 kt

Stall: 79-105 kt

1.3 Vso: 103 kt

ROC: 2200 fpm

SE ROC: 420 fpm @ 152 kt

SE Service ceiling: 12,000 ft

Min field length: 2200 ft

Cabin press: 6 psi.

Fuel cap: 2439 lb

**MU-2P**

Engines: 2 x AiResearch TPE 331-5-252M, 665 shp

Props: Hartzell four-blade, full-feathering, reversible

Length: 33 ft 3 in

Height: 12 ft 11 in

Wingspan: 39 ft. 2 in

Wing area: 178 sq. ft

Wing loading: 58.8 lb/sq.ft

Power loading: 7.9 lb/hp

Seats: 7

Empty wt: 7,050 lbs

Useful load: 3,420 lb

Payload with full fuel: 1,236 lbs

MTOW: 10,470 lb

Usable fuel cap: 364 USG/2,184 lbs

Max landing wt: 9,955 lb

Max ROC: 2,450 fpm

SE ROC: 475 fpm

SE climb gradient (150 kt Vyse): 190 ft/nm

Service ceiling: 32,200 ft

Certificated ceiling: 28,000 ft

SE service ceiling: 16,800 ft

Max cruise at 16,000 ft: 306 kts

Econ cruise at 24,000 ft: 272 kt

Duration at max cruise: 3.9 hrs

Duration at econ cruise: 5.9 hrs

Stalling speed, clean: 103 kts

Stalling speed, full flaps: 78 kts

Pressurization differential: 6 psi

10.000-ft. cabin at: 31,200 ft.

Mitsubishi MU-2