Tilt-Rotor Aircraft

[elmayerle]

I've seen it.  Now I want to see them demonstrate a 3-D swarm to "Flight of the Bumblebee".

[Stargazer2006]

Truly amazing stuff.

[Rafael]

Those guys really hit it off with the swarm mentality.

A question aside; what about a tilt-propfan? The counter-rotating daisies of José Fernando's OV-23 Observer made me think.....

[elmayerle]

A question aside; what about a tilt-propfan? The counter-rotating daisies of José Fernando's OV-23 Observer made me think.....

Feasible, as long as you're not trying to meet some of the stowage time requirements the V-22 had to meet.  On the other hand, you won't have the same hovering efficiency (that's one thing that's made tilt-wing aircraft expensive - now, a tilt-wing with engine and rotor on the wingtips might be something as long as you don't have that stowage requirement).

[Rafael]

A question aside; what about a tilt-propfan? The counter-rotating daisies of José Fernando's OV-23 Observer made me think.....

Feasible, as long as you're not trying to meet some of the stowage time requirements the V-22 had to meet.  On the other hand, you won't have the same hovering efficiency (that's one thing that's made tilt-wing aircraft expensive - now, a tilt-wing with engine and rotor on the wingtips might be something as long as you don't have that stowage requirement).

Ok, engine and rotor it is. But, for example, for a small strike craft á la gunship or small transport in the league of the Sikorsky S-97 Raider X2 would it be feasible to use propellers the size of those in the XFY-1 Pogo?

[elmayerle]

Close enough, if you want a bit bigger, use the props from a 1/48 Pogo on a 1/72 tiltrotor; I have seen some speculation on contra-rotor tiltrotors so there's possibilities there, too.

Figure you're going to want something in the 1000 shp for each engine.  I'm also inclined to suggest a straight-thru engine rather than a reverse flow one like the PT6 as I'm given to understand that the exhaust for this engine on what's now the AW609 is somewhat problem-prone.

[GTX_Admin]

Early AEW Tiltrotor proposal:

[GTX_Admin]

For other possibilities, how about an AEW radar mounted on the aft ramp much like what the FAA has on Sea Kings now?

Like this perhaps?

[elmayerle]

Yes indeed!!  That most certainly looks highly do-able.

[apophenia]

Evan: Boeing-Bell proposal for a commercial tilt-rotor based on the DHC-8 fuselage.

[Silver Fox]

Tilt wing rather than tilt rotor, but it's a BattleTech 'Mech. For when you really want to drop in and kill something.

[elmayerle]

That's pretty much the approach I'm planning to take, melding the V-22 wing and nacelle installations to a Dash 8 fuselage and adding sponsons for the main landing gear.  Hmm, that HC V-22 may be a good contributor to this as its engine nacelles are much closer to a civilian design than what the military flies on the V-22.   I've got some bits and pieces that'll make good shapes for the sponsons.

[M.A.D]

A few of my tilt-rotor whifs for your enjoyment... (I hope).



Grumman OV-1H Mohawk II



The Grumman OV-1H Mohawk II was the next logical step in the evolution of the reliable and flexible G-134 design. Featuring widened and shortened wings, it became the first operational tilt-rotor in the U.S. inventory when the Army took delivery of the first aircraft in June 1986. The G-134TR Mohawk II proved a valuable asset in difficult missions over Panama and Nicaragua, where the hostile environment made landing impossible to the original version. The Mohawk II was used for observation (OV-1H), as a rescue aircraft (HV-1H) and as an armed counter-insurgencency type (AV-1H). On top of the 110 new examples built by Grumman, most Mohawks remaining in the inventory were overhauled and brought up to "II" standard, bringing the total in operation up to 250. These versions, although externally similar to the new frames, presented a number of technical differences and were therefore designated with the use of the "J" suffix letter instead (OV-1J, HV-1J). There were no AV-1J conversions, as all 60 COIN aircraft were new from the factory. Finally, a small utility transport with deepened fuselage was produced in 12 examples (UV-1K). The last Mohawk II was retired from service in May 2003, making the G-134 family one of the most enduring designs in U.S. service.




Vought V-498 Bluebird VTOL



Some may remember my Vought-Sikorsky Shrike (then again you may not... lol). Well, anyway, here is another take on the LTV XC-142 concept, the LTV V-498 Bluebird (which derived its name from Vought's very first aircraft). It was produced in small numbers for a few regional airlines in the U.S. and Canada, such as the now defunct New York Airways, seen here.




Bell-Boeing CV-22C Long Osprey



The Bell-Boeing CV-22C Osprey is a new transport variant for the US Navy. It can be seen here on take-off trials from USS Harry Truman (CVN-75) in June 2015. The tough part in this picture was not to create the CV-22C from the regular version... it was coming up with a complete picture of the aircraft-carrier's tower! I had to rework it from several pictures...




Boeing-Lear CV-24A Hummingbird



What if Bell/Boeing's V-22 had not been the first operational VTOL? What if Boeing had teamed up with Learjet instead to offer an heir to the old X-19 concept and make it work as a liaison/VIP transport? This is what the fake advertisement above is all about.




And finally a tilt-duct... Not quite what this topic is about, but since someone included a tilt-duct above, I may as well add mine here.


Boeing-Bell XV-16A PLR VTOL



Contrary to popular belief, The V-22 Osprey is not the first joint effort by Bell and Boeing. In 1976, Boeing Vertol teamed up with Bell's Helicopter Division on a proposal for the Army's PLR (Power Lift Rotorcraft) program. Designated XV-16A in the VTOL series, this clean-looking and able performer combined Boeing's experience with transport helicopters and Bell's expertise in VTOL, in this case capitalizing on the tilt-duct research that culminated in the highly successful X-22A prototype a decade before. The PLR program was canceled despite a successful two-year evaluation phase because it was found that its advantages did not outweigh the 35% increase in costs from operating it instead of a conventional Chinook.

Awesome work and effort Stargazer 

M.A.D

[Stargazer2006]

Awesome work and effort Stargazer 

M.A.D

Thank you so much!!! 

[Logan Hartke]

Where've you been, Stéphane?  I haven't seen much of your work, lately.

Cheers,

Logan

[Stargazer2006]

Hi my friend! Too busy with the SPF, SRF, What If forums and other aircraft-related research! That explains my being less active on this particular one. But have no worry, I still roam the place and post from time to time...

[GTX_Admin]

Evan,

Are you at liberty to talk re this?



More

[elmayerle]

Evan,

Are you at liberty to talk re this?



More

In a word, no.  I am familiar with the test installation and the various R&D activities supporting it (there are some less than obvious concerns) but I don't have leave to talk further.  For that matter, I don't yet have leave to discuss the V-22 mod program I was involved with.

[GTX_Admin]

Fair enough.  Maybe one day.

[taiidantomcat]

I know its already been done by one of our intrepid whiffers 


Sure looks good though 

[elmayerle]

I note that the latest issue of Combat Aircraft (at least the latest one on US stands) has a picture of "N204TR", the testbed I've been working on.  I don't know that I can comment on it, but it is a very good picture.

[Rickshaw]

Evan,

Are you at liberty to talk re this?



More

Looks like some effort to smooth airflow.  Do the finlets move or are they stationary?

[elmayerle]

They are stationary.  Think of a variation on winglets.

[Rickshaw]

They are stationary.  Think of a variation on winglets.

That was what I suspected.  However, they could possible have been for better control.  Interesting in and of themselves though.   Obviously airflow behind those big rotors is more than a bit turbulent! 

[elmayerle]

They are stationary.  Think of a variation on winglets.

That was what I suspected.  However, they could possible have been for better control.  Interesting in and of themselves though.   Obviously airflow behind those big rotors is more than a bit turbulent! 

Quite.  The V-22 has a most noticeable sound, quite distinct from any of the other aircraft in the test fleet here.