Intro to the MU2 #1 -- Design Features

What makes the MU2 such a capable airplane? This will touch on a few of the big points. Sorry about the wind noise; it gets a little better after the first minute. Here is the outline:
o 1) It was designed from a clean sheet of paper to be a high performance, turboprop aircraft, unlike the King Air, Commander or Conquest, all great airplanes, but also all derivatives of earlier piston airplane designs.
2) The engines, wing and landing gear, therefore, were designed from the beginning to handle the power, air and landing loads that come from turbine operations.

o This is a Mitsubishi Marquise, or MU2B-60, the last iteration of the long body variant of the type. It has a Maximum Gross Takeoff Weight of 11,575 pounds and a useful load of 3,725 pounds. It cruises at 280 knots true at typical cruising altitudes and has a range greater than 1100 nm with reserves. The wingspan of the MU2 is less than 40 feet, 13-15 feet less than the other airplanes we talked about. This is how the Mits got its high cruise speed: less wing area = less drag. The small wings also provide a side benefit of a better ride in turbulence because of the resulting 65 pound/square foot wing loading, similar to a Learjet. A pair of Honeywell/Garrett Dash 10 engines doesn't hurt, either. They each have 1000 SHP, flat-rated to 715, plus 157 pounds of jet thrust.
 An inescapable side effect of a small, highly-loaded wing is a high Vs, in this case 100 knots. Something had to be done about that to get into the short strips we pilots wanted to use. Remember the "U" in MU2 stands for "Utility". The solution is full span, double slotted Fowler flaps, common in airliners, but not found in many GA aircraft. These increase wing area and lower stall speed dramatically. Vso at Flaps 40 is 76 knots which, combined with the high wing design reducing the tendency to float, lets us land at typical weights in less than 2000 feet over a 50 foot obstacle. Ground rolls of less than 1000 feet are achievable, if you need them, as we do at Mountain Air to provide the safety margins we desire.
 Great. We have high cruise speed and good short field performance, but we also have an already small wing that we have stuffed full of flap. This raises two questions:
• Where do we put enough fuel to get decent range?
• How do we turn this thing?
o The fuel question is answered with tip tanks. 180 of our 403 gallons are carried in the tips.
o Since we don't have room for ailerons, Mitsubishi used spoilers for roll control, just like they did for the Diamond I, which later became the Beechjet and is now the Hawker 400. They work great, virtually eliminating adverse yaw, but require single engine procedures unique to the MU2, similar to jet engine-out procedures.
Speaking of single engine procedures, one thing you may have heard is that MU2s have an issue with their relatively high Vyse, or blueline speed of 150 knots compared to the Vr, or rotation speed of about 100, the idea being that you are in an unsafe condition for the long time it takes to accelerate these 50 knots. Although Flaps 0 blueline is indeed 150, the statement as presented misses two important points:
First, the airspeed you are really trying to maintain if you have an engine failure shortly after takeoff is Vxse, not Vyse, since that is what will keep you out of the trees.
Second, takeoffs in the MU2 are almost always done at Flaps 20, occasionally at Flaps 5, but never intentionally at Flaps 0, so the 150 knot blueline target is not an initial part of the engine-failure-immediately-after-takeoff scenario. Vxse at Flaps 20 (the speed we want) is 125 knots and is achieved so quickly after becoming airborne that the incremental risk compared to other aircraft types, if it exists at all, is certainly manageable.
Also contrary to myth, what the spoilers don't do is cause the airplane to roll about the wingtip; the MU2 rolls the way every other airplane rolls, about its longitudinal axis. There are also no peculiar crosswind techniques for the MU2. It does have a fairly narrow track landing gear, so you need to pay attention to the deceleration and rollout of every landing, making sure the props reverse evenly, crosswind or not.
o That brings us to the final major component of the design which contributes to the MU2's runway performance: its landing gear. It is extremely rugged, with high flotation, low pressure tires. Mounting the gear into the fuselage instead of into the wings allows the airplane to easily handle very firm landings and unimproved airstrips, while allowing the wings to be designed to carry only the air loads, not landing impact loads.

Category:

Autos & Vehicles

Tags:

• MU2
• Mitsubishi
• Airplane
• Turboprop
• Mountain
• Air

[manifestgtr]

hahahah the best part of this video (besides the incredible aircraft and seemingly cool guy) is the wind noise over the parts you really wanna hear

"for instance *whoooooshhhhhhh*"

[mtnairpilot]

@manifestgtr I posted the outline in the description. Hope that helps. Thanks for watching.

[KingOfBanks]

The most negative comments I've heard about MU2s have all come from pilots who have never flown them, and their opinions are generally from a guy who knows a guy who met a guy who was some sort of hot shot. They require comprehensive training to be operated safely if I'm correct. In Australia, we must by certified for every turbo-prop, unlike the USA (I think). PA34 into an MU2 with no extra training? They don't seem conventional enough to do that.

[mtnairpilot]

@KingOfBanks Agree 100%. The US FAA did implement SFAR 108 in 2006, effectively requiring a type rating and annual type-specific recurrent training for the MU2. Since then the accident rate has dropped sharply.

[tubepusser]

MYTH! I trained on the MU-2 for 15 years and used to buy into you say. We soon found that the manual was right and it climbs better with the flaps 5 or up. At gross weight we got no rate of climb (MU2J&L) with flaps 20, 200 fpm at 5 and 500 fpm at zero using Vyse. At Vxse we got better climb gradient by far with the lesser flap settings. We flew a Lear 24 also and there is NO similarity as the Lear has so much better power/weight ratio and does OK with flaps down single engine.

[mtnairpilot]

@tubepusser Setting aside the power difference between a Marquise and a J or L model, in an engine failure after takeoff scenario, accelerating to a flaps 0 or flaps 5 speed before you hit the trees may not be an option. My comparison to the Lear related only to wing loading, which is a fact. I don't think I implied that single engine performance was comparable.

[tom080955]

You've probably got some great wisdom to share that the wind seems to keep you from sharing ;-)

[mpgingdl]

The MU-2 is unique in another respect: even when parked on the ramp, it still looks like it's doing 300 knots.

[47colton]

Thanks for showing the airplane. My old friend J." Mac" McGrath flew the small mu-2 from the 60s to the 80s from a 2300 ft strip. He was the highest time mu2 pilots for many years.rt

[MSLTUL]

Any chance on remaking this on a day with far less wind? Also, I want to see the flaps and spoilers extended. When you've made an effort to be out there at the aircraft, it doesn't make sense to talk about "full span Fowler Flaps" when they're tucked away. Same goes for spoilers, etc.

[Mega2toes]

Wow, lots of wind noise in this video. Couldn't hear most of what you were saying.

[psyjpg]

@tom080955 They are claiming (above) that the MU2 is a 'man killer'. Is that true? How do you respond to that?

[psyjpg]

@PlasticC4 what do you mean 'man killer'?

[tom080955]

@psyjpg lol

thanks for the reply. have you made any others or updates on this fantastic aircraft?