Quad Tilt Rotor

[kitnut617]

Having followed the recent thread on the Rotodyne, I've been giving the subject some thought as to the comparison between it and a quad tilt rotor.

Unfortunately, as much as I love the Rotodyne ( I have one to build and I will almost certainly build a larger one, probably using a Herc' as a base) I think the quad rotor has the legs up on it.

There's a number of line of thoughts I've had about it and there is one advantage that the quad has which hasn't been discussed.  But before I get into that I have to say that when the V-22 is in forward flight mode, it reminds me of a couple of other aircraft, ones which were built a long time ago.

These would be the V-173 and XF5U-1, the Flying Pancakes.  I have these two in model form and I bought the Ginter book on them at the same time as when I got the models.  The V-173 had the ability to take-off and land at not much more than 30 Knots and when used on a carrier which had 30 or so knots of wind across the deck would seem to be taking-off or landing vertically!

It was able to do this, not so much as having a high lift wing (it didn't) but more because about 90% of the wing was downstream of the prop wash.  Now this strikes me as being very similar to the tilt rotor as both aircraft have the center of the prop at the wing tip and almost all the wing is downstream of the prop wash.

On the V-22 this isn't very obvious because it has to have the rotors set for vertical flight until it gets enough altitude to rotate the props into forward flight.

This is not the case on the quad rotor transport as the rotors have enough ground clearance to be left in the forward mode while on the ground.  This aircraft if produced, could have incredibly short field perfomance where the wings with all the high lift devices extended and the prop wash flowing over the surfaces, it could produce it's own lift much like how a boundery layer wing might work.

I aim to build one of these too and the attached rendering of how a quad rotor might be deployed is probably how I would build mine, but have a look at the fuselage and tell me what it looks like (hint: not a Herc')

Robert

Edit: the rendering is off  the Popular Mechanics website.

[jcf]

I aim to build one of these too and the attached rendering of how a quad rotor might be deployed is probably how I would build mine, but have a look at the fuselage and tell me what it looks like (hint: not a Herc')

Robert

Revell Transall bash Numero Uno coming up?


Cheers, Jon  

[Archibald]

Just a thought : it could be funny to buy two similar Hercs and changing the first into a Rotodyne, and the second into a QTR

[kitnut617]

Revell Transall bash Numero Uno coming up?


Cheers, Jon

Exactly what I thought Jon.

Archibald, yes that would be neat too

Robert

[Archibald]

This could be a kind of group build : change a basic  C-130 into a STOL / VTOL cargo.
Various solutions

- 1 a la Breguet 941. Shorter wings, bigger props to blow the whole wing. Add flaps
- 2 a la An-74 / XC-14 or XC-15 : podded jets, coanda effect
- 3 a la Rotodyne
- 4 a la CL-84 (tilt wing!)
- 5 a la QTR (four tilt props!)
- 6 a la HS-681 : podded engines with Harriers exhausts!

If anybody have others suggestions (lift engines or else...)

In every case, a QTR Transall could interest the AdA or Aeronavale to replace the Super Frelon heavy lift helo... love your idea, Robert  

[Mossie]

I'm looking forward to this one Robert!  I guess thats what your doing with the Transall once you've whipped the Tynes from it then!

Spookily, we often think along similar lines!  I've just knocked up another Rotodyne profile, a gunship! I  guess it would be used in a similar role to the one in your pic.  Is this how you plan to build yours mate?

The QTR Transall/gyrodyne Herc would make fantastic comparison builds, can't wait to see them!

Simon.

[Shasper]

- 2 a la An-74 / XC-14 or XC-15 : podded jets, coanda effect

Sounds kinda like that C-123 that got Fd up for the movie Die Hard 2, it had 4 jets mounted in a similar fasion, plus the original jet pods.

Shas B)

[kitnut617]

I'm looking forward to this one Robert!  I guess thats what your doing with the Transall once you've whipped the Tynes from it then!

Spookily, we often think along similar lines!   I've just knocked up another Rotodyne profile, a gunship! I  guess it would be used in a similar role to the one in your pic.  Is this how you plan to build yours mate?

The QTR Transall/gyrodyne Herc would make fantastic comparison builds, can't wait to see them!

Simon.

Yes, I've been searching for the kits, and if I can't find them I'll use the Gabriel I've already got.  The V-22's are still regularly available.  The Tynes and the wings would go and to convert the Heller kit of the C160 has an advantage (not sure if the Revell kit is the same) because when you assemble the wing you build the whole wing seperately, the wing, wing root and top of fuselage in this area are one.  Filling the space in the fuselage would be quite easy and no major chopping of the fuselage at this point. In fact there's not much to do to the fuselage except the tail area.

Anyway, my reno's to my house are almost complete so soon the house will be on the market, then it's just a matter of finding a place to buy, then I can get back to modelling.

Robert

[jcf]

The Tynes and the wings would go and to convert the Heller kit of the C160 has an advantage (not sure if the Revell kit is the same) because when you assemble the wing you build the whole wing seperately, the wing, wing root and top of fuselage in this area are one.  Filling the space in the fuselage would be quite easy and no major chopping of the fuselage at this point. In fact there's not much to do to the fuselage except the tail area.

Here is the kit preview from Hyped-Scale:
Revell Transall

Cheers, Jon

[philp]

wikipedia has some more on this idea.
Like the cutaway.

[simmie]

When the QTR was first suggested, Bell said that they could convert a Herk as a proof of concept aircraft.  This was quietly forgotten when they realised how much work would be involved in creating wing mounts on the front of the fuselage.

How about using a CH47 Chinook as the basis??  Replace the rotor masts with Osprey wings, extended at the rear and a vertical tail.  even better would be the stretched Chinook that Boeing built in 1970 as the model 346.  As well as a streach it had uprated engines, improved transmission, retracable undercarriage, improved flight controls, taller rear mast and 4 blade rotors (a potential what-if in it's self).

If you want to improve the herk, espacilally the long ones (C.Mk3 and C.Mk5) fit a variable incidence wing so that you get the sharp climb out without trailing the longer rear end along the ground!

[Mossie]

Simmie, I've toyed with the idea of using a Chinook as a basis for my Rotodyne Z build, but I'm not sure of the fuselage dimensions.  I think if someone wanted to use this as a basis for either a gyrodyne or QTR it'd work well.

This could be a kind of group build : change a basic C-130 into a STOL / VTOL cargo.

Archie, that's a good idea!  Maybe not limit it to the C-130 (I've got a C-160 fuselage that needs something doing to it), but convert a current transport aircraft or helicopter in to some kind of STOL/VTOL concept (but not a straight helicopter!).  You could include your HS.681, or something along those lines.  It opens it up for all kinds of weird & wonderful machines!

There's been all kinds of VTOL/STOL designs over the years, ducted fans, tail sitters, multi-lift engines, vectored thrust, I'm sure the list of things we could come up with are endless.

[kitnut617]

OK, I'm jumping ahead a bit here.  We have a Herc/Transall QTR now but what if we wanted to go bigger  (Why?, just because I want to)

What do we have that's between the C-130/C160 and the C-17 in the way of a transport lifter? Is there an in-between lifter that could be used that I'm forgetting?  I think it would have to have a fuselage diameter about the size of the C-17.  Maybe a Belfast?

And what engines could be used?  Some things that have been running through my head    are,


---- wait for it ---    



How about a tilt Hi-Bypass Turbofan, you know, RR Trent size      

Robert

[Mossie]

Robert, I posted in the HS.681 thread that a Kawasaki C.1 might make a good basis for a conversion, but there's only a 1/200 Hase kit available that I know of.

An-12 around the same size as a C-130.  C.141, Il.76 & An-22are a similar size to the C-17.

Rumours are that Revell are serious about kitting the A400M, maybe you could use one of those & it'd fit right in the middle between the C-130 & C-17.  The An-70 would have fit in too, if only eh?

Not too helpful I'm afraid, either everything I think of is a similar size or you can't get a kit of it!

[Archibald]

Revell are serious about kitting the A400M

Long life to Revell! Which scale is planned ? (not 1/72 I'm affraid...)