Check this Vader-like black MU-2 out with brand new MT 5-blade props. If there’s an equivalent to a pinup picture for pilots for inside the locker, this would be it for me. Sex with props!
It looks great – I can imagine the owner wanting to further capitalize on the MU-2s reputation with a serious looking paint job. Wonderful.
Are the props wood? The blades look the same as those on my MT, wood construction retained by lag screws into the grain, with a thin layer of glass on top and a stainless leading edge. Seems to me that ten of those wood blades on all weather plane might be a maintenance challenge!
Silvaire – yes, they are wood core. Or “natural composite” as MT likes to call them. Covered in carbon fibre and glass, so no water gets to the core. Except for less abrasion resistance, I’ve not heard bad things. They’re a lot lighter than the old 3-blade props as well.
However, I’ve heard on the Beech forum that the 3-blade slows the Bonanza down between 3-5kts, so there’s no real speed gain. Same on the Aerostar – the 4-blade climbs better and has less vibration, but isn’t any faster. They just look cool.
On my 3-blade MT the composite sheath is one layer of fiberglass, so thin you can see the wood grain through it. That’s not necessarily bad, but they’re really wood props in the sense that blade form and performance is limited by material strength. 99% of the blade is wood. Also, the mechanically formed stainless steel leading edge is crude in comparison to the electro formed nickel used by others. I think the neat thing about the MT props is that they can be overhauled almost indefinitely… balanced by the fact that they need to be overhauled more often due to the fragile blades. They seem to be designed to fit the European regulatory regime in which propellers get overhauled on a fixed schedule, whether they need it or not. So no cost benefit allowed for higher durability.
I had mine overhauled last year. Yes, its quite smooth.
At 360 KTAS, 3-4 knots no big deal!
In the Sixties (I know, if you remember them you were not there), the MU2 was a regular on the big air show circuit and very impressive – although did not match Hoover and his Aero Commander.
They seem to be designed to fit the European regulatory regime in which propellers get overhauled on a fixed schedule, whether they need it or not.
We know about your allergy to things invented after 1950 outside the US but as a private owner (Part 91 equivalent), you can use props indefinitely as long as they are deemed serviceable by your Part 145. Maybe not in all EASA countries but most.
Also, the mechanically formed stainless steel leading edge is crude in comparison to the electro formed nickel used by others.
I would attribute greater strength to the stainless steel compared to nickel. The killer argument for MT’s stuff is weight and the excellent shock absorption characteristics of wood. The weight allows them to have more blades which are shorter and thereby reduce noise — something very important in Europe and one day also in the US because it directly translates to quality of life. Of course there are other lightweight materials than wood composite but none are really proven yet. The A400M propellers are composite and they are the meanest so far with 12,000hp each. Don’t want to know what they cost to make and what their service intervals are.
At 360 KTAS, 3-4 knots no big deal!
That’s not true. Anyone buying and flying a 360kt aircraft is going to be upset if it goes slower after an expensive prop upgrade. It may not be rational but it is a fact.
Your next airplane, Adam?
On a G-reg you have a mandatory 6 year overhaul.
I did one anyway despite being N-reg and it cost £3500. That is a significant cost for many people.
I am about due for another now but I am not doing it since the prop is in a great condition.
Bear in mind also, FWIW, that the usual collection of antennae costs you ~2-3kt at 150kt and probably more at 300kt+.
I looked at the MT prop on a Meridian and while they are very attractive, essentially there is no performance gain so it is purely spending money for the look of the thing. Nothing wrong with that but they are not cheap. Fair enough if you need a new prop anyway but I can think of better ways to spend the €40k per prop.