Originally Posted by Kiwiguy
Roethesod about the Mu-2 which I have never flown personally, I gather they all have some difficulty with power levers (constant speed pitch levers)down between the pilot's seats being vulnerable to being knocked or having a friction nut deficiency. I gather that it is not uncommon for one of the power levers to retreat without the pilot noticing.
This plane is a well known widowmaker and the issue seems not with the engines, but with deficient power levers.
The problem we had with our MU-2 was nothing to do with power levers, I don't recall ever experiencing the 'wander' you describe. We had what was described as a 'torque shift'. I don't pretend to understand the Garrett 'single red line' instrumentation system, but what we actually experienced was a slow reduction in the starboard engine torque over a long period of time (100s of flying hours) so that, at the time of my airtest there was 10 - 12% less torque with identical on-board engine indications. Our investigations prior to the said test flight were extensive and included blade angle, idle fuel flow, flap spoiler and trim-aileron rigging checks etc. The engine malfunction was only discovered when we had the actual torques checked with a Le Beau (apologies for spelling?) meter, a device which is fitted between engine and prop - not the kind of equipment normally held by a small fleet. As far as I know Garrett had never advised that the torque gauge indications could be totally meaningless (100% torque was 100% of what was available on an engine, nomatter how sick and underpowered it was, it seems).
I agree with your appraisal of the aircraft's safety reputation and I may be wrong but I never heard of any pilots being sued by Lockheed for calling the F-104 a 'widow-maker' (fwiw a very fine aircraft in my opinion). Many MU-2s were lost in the USA prior to my complaints to Mitsubishi about its asymmetric handling characteristics. The AFM quoted Vmca as 93kts in those days (1984-ish). We complained about difficulties our trainee pilots were having with EFATOs and were asked 'at what speed did we make the 'cut'?' When we told them 105kts+ they were amazed and said 'NEVER BELOW 125kts'. It appeared that the low Vmca was there to sell the aircraft's short-field performance. We suggested this and that they review their AFM. Probably the fastest AFM ammendment on record followed and the Vmca was increased to 115kt IIRC. We immediately ceased our Nigeria MU-2 operation and sold the aircraft (which had been bought specifically for VIP flights into a performance limiting field after thorough AFM study).
rts