COIN attack helicopters

Over the past several years there has been much talk about COIN aircraft for use in Afghanistan. While it may be unlikely the USAF buys such an aircraft, there is indeed a requirement for the Afghan air force, and most of the proposals seem to be rather light, turboprop powered designs.

But why hasn't there been any interests in new helicopters with COIN warfare more in mind? The AH-64 has provided excellent service in Afghanistan but naturally it isn't perfect. Could something faster, better armored, and with a greater payload be useful? Some features of the Lockheed AH-56 and Sikorsky S-67 designs seem like they would be ideal for Afghanistan, particually their speed and room for growth. A modernized version of either design would be close to my ideal COIN attack helicopter, but seeing either would be impossible today.

Yet Sikorsky and other companies can certainly produce helicopters with similar performance. Sikorsky's X2 configuration seems ideal for the role, and they even produced concept art of a design that resembled the RAH-66 Comanche using this configuration. Now apply that to a larger, better armored airframe and I imagine it could be incredible for CAS work.

Would such a design still be useful despite the plan to leave Afghanistan in a year or so, or would it be a waste? Could it carve out a role in more conventional types of warfare? Or would it simply be impossible for the Army to have both a dedicated tank-killer (AH-64) and something of this nature? With today's focus on COIN warfare, you would think there would be some focus on high-speed close air support focused helos, or does the lack of any official requirement prevent such development?

Interesting ideas. I'd assume that fuel efficiency and loitering ability would be important (one of the reasons why Oh-58s do well in Iraq). It would seem that COIN requires a lot more flight hours per engagement than tank busting does. A certain amount of COIN is surveillance and deterrence after all. An aircraft like the AH-56 is simply too hard to maintain and heavy to be "ideal" (it might still be good at it though).

Soviet designs coming out of Afghanistan recommended 360 degree gun coverage (ie. Mi-36, Mi-40 and the ill Mi-24 rear gunner modification). So, this also might be a good idea.

I remember this had inspired me to sketch out a design with only two hardpoints, but with forward and aft gunners/observers carrying relatively light weapons and a 30mm cannon with 360 degree rotation mounted at the center of gravity with extra heavy duty recoil dampers. An escort gunship with two sets of sensors and three turrets. However, this might be too heavy and expensive to loiter well.

So, anyway, a very interesting question.

Since I wrote that post Sikorsky has revealed their S-97 Raider concept for the AAS program, while not exactly an attack helicopter it looks like it could be a major leap over the current OH-58. The S-97 and the Joint Multi-Role (JMR) rotorcraft program could lead to some interesting developments. While I doubt we will see an attack helo designed specifically for fights like Afghanistan, I imagine new designs will incorporate lessons learned there, particularly in terms of armor and survivability.

JMR is supposed to replace the Blackhawk and Apache correct? I presume they are looking at two variants sharing components (like LHX) as opposed to some sort of modern day Hind.

Who's going to fly it, maintain it and support it?

The Afghan Army / Air Force would be better off buying Mi-17s and Mi-24s. You don't need a state of the art tank killer for COIN work, especially in a third world country. What they need is something simple and cheap to operate, simple to work on, and effective.

Of course, what will probably happen is that the US will "encourage" them to buy expensive systems they don't need.

I agree that the COIN mission is one job where hovering is less important than loiter time and VTOL. I wonder if there would be a role for a modern autogiro in today's COIN world? It's not hard to imagine a rugged, armored autogiro with jump take-off capability as the little friend that stays on station while the big guys come and go. With a chin or belly turret it could also orbit to provide suppressive fire like a baby gunship, .50 cal would be enough.

COIN attack helicopters and loitering fixed-wing...

Would another advantage of autogyro be low thermal signature ?

FWIW, slightly OT, I'm reminded of the Edgley Optica, a UK fixed-wing design intended for *civilian* loiter / surveillance. It behaved more like a micro-lite than either fixed-wing or helo. IIRC, it could fly so slowly that it took a civilian pilot unawares. He apparently stalled in a slow turn and crashed, destroying the design's prospects...

http://en.wikipedia.org/wiki/Edgley_Optica

Uh, given the Stans' 'hot and high' requirements, I'd go for a twin-engined DeLanne design, as they tend to have low wing loadings, high tolerance for c/g position and tame stall behaviour...

You could hang an attack 'copter's optics and chin turret off both front and back, while that 'almost stagger-wing' layout offers a lot of space for hard-points...

Re: COIN attack helicopters and loitering fixed-wing...

I have often thought that both the Delanne tandem and variations on the Mignet tandem configuration had great potential for low-speed military applications. Easy wing folding, short span, stall- and spin-free handling--just what you want in light observation or COIN. Take a look at the Croses Paras-Cargo in an earlier thread of mine, Adapting the Mignet configuration to other categories. Several designers have used the Mignet configuration with pusher engines--Landray Pouss-Pou, Briffaud Pou-Push, for example. It's not hard to imagine a pusher-engined Mignet tandem with stepped tandem cockpits, turretted optics and gun and a couple of hardpoints as the eye in the sky to escort road convoys and patrol the skies for long periods, ready to call in whatever is needed to get the job done for anything it can't handle.

Nik said:

Would another advantage of autogyro be low thermal signature ?

FWIW, slightly OT, I'm reminded of the Edgley Optica, a UK fixed-wing design intended for *civilian* loiter / surveillance. It behaved more like a micro-lite than either fixed-wing or helo. IIRC, it could fly so slowly that it took a civilian pilot unawares. He apparently stalled in a slow turn and crashed, destroying the design's prospects...

http://en.wikipedia.org/wiki/Edgley_Optica

Uh, given the Stans' 'hot and high' requirements, I'd go for a twin-engined DeLanne design, as they tend to have low wing loadings, high tolerance for c/g position and tame stall behaviour...

You could hang an attack 'copter's optics and chin turret off both front and back, while that 'almost stagger-wing' layout offers a lot of space for hard-points...

Click to expand...

"..It's not hard to imagine a pusher-engined Mignet tandem with stepped tandem cockpits, turretted optics and gun and a couple of hardpoints as the eye in the sky to escort road convoys and patrol the skies for long periods, ready to call "

Why not base it on the Lockspeiser LAD-01 ?
(for example : http://vads.ac.uk/diad/article.php?title=278&year=1972&article=d.278.31)

It's of course purely fictional, but could have all charactersitics, you've asked for. And ..
a kind of prototype has already flown !

The Lockspeiser is a neat design but the canard is awkwardly placed for this sort of use. There is nowhere but the fuselage for hard points near the CG and the canard would be in the line of fire. A Miles-type tandem with the front wing high and the rear wing low might work better, with the turret moved forward or aft if it is always installed and the space near the CG reserved for disposable stores.

The belly turret might work even with a tractor engine--a light aircraft should avoid straight strafing or bomb runs which make it more vulnerable to ground fire. The turret allows it to orbit like a gunship from a safe distance or to keep the target under continuous fire if it must pass overhead. One of the new lightweight, low recoil .50 caliber machine guns being fielded by the U.S. Army for infantry use would be perfect.

Surely should have stumbled acros the this type earlier, when reading this post :
In its current form, the HESA Shahed 285 looks like an attempt to minimize, what
an attack helicopter needs. The only onboard sensor seems to be the Mk.1 eyeball
of the single pilot, so long range weapons aren't useful either. Flying the heli and
aiming a weapon would be too much of workload, so the relatively light gun is (more
or less) fixed. What looks like a faceted fuselage, to my opinion has nothing to do with
stealth, but with light armour of vulnerable parts.
Not an attack helicopter in common sense, but as a COIN aircraft it probably could replace
larger and more powerful attack helicopters in a number of roles. At least, as it is known
in advance, what is needed and the insurgents, that are to be countered aren't too well
equipped.

http://www.secretprojects.co.uk/forum/index.php/topic,894.msg115910.html#new