I was lucky enough to have the opportunity to fly a XV-15 Tilt-Rotor in a high fidelity research simulator yesterday and it got me thinking.....
I have never been a big fan (geddit BIG FAN) of the tilt rotor concept at all, its not a good aeroplane, and its a terrible helicopter. So is it worth the technical difficultly?
With the ERICA and EUROTILT programs and the V22 & BA609 supposidy on the way, sooner or later some of us will be asked/expected to fly these things so I though it might be a good time to have a general chat about them.
I'll start things of with my two-cents....
Starting from the ground and then lifting into the hover and doing a spot of hover-taxiing I found the XV-15 to be really easy to fly (admittly I was getting lots of help from the spurious black boxes on board) but even so no big deal....very stable. The thing was very docile in yaw....lot's of pedal required to get it turning on the spot thanks to the tonne of engine and prop at the end of each wing! Flying around was just as easy and VERY VERY fast 260kts!
I have often wondered how the controls are laid out in a Tilt rotor - it's actually really neat, the collective remains as a collective in all flight regimes - up and down in helicopter mode and fast or slow in plane mode. The cyclic is a cyclic in heli mode but converts to being a stick/yoke in plane mode - the electronics handle the blending of the controls in transient speed ranges. The nacelle tilt in this set-up was handled by a coolie hat switch on the cyclic - three positions.
While everything was easy enough with an instructor talking me through the systems as I flew, I can't help thinking that the failure modes for these things are so much more complex. So complex in fact that the pilot wouldn't be able to react quick enough (to a complecated situation) to be able to do anything useful.
Furthermore, the differential ring vortex problem will also no doubt be a real danger for these craft, bank in helicopter mode at low forward speed and all of a sudden one rotor is in ring vortex state - WOLLOP.....Ouch!
I've also heard lot's of mutterings that the range and payload of real incarnations of these aircraft are also marginal.
What do you think......are they worth the bother? Would you fly them? Would you tell your granny to fly in one? Any real tilt rotor pilots out there?
CRAN
