Cheap CAS/COIN is an Illusion – Lets Get Off the Bandwagon


Listen to anyone these days (even this blog!) and they all say we must have a turboprop close air support and COIN aircraft. The US has issued various requests for information and is pursuing the concept under the Imminent Fury programme. Will any of these programmes go ahead, who knows, but we thought we would have a look at the arguments and why the groundswell of opinion seems to favour going back to turboprops to deliver combat effects.

The drive to reduce costs leads to the conclusion that a low priced aircraft is the answer and Embraer have proposed the Super Tucano, Beechcraft the AT-6, Air Tractor with the AT802 and even Boeing have pitched in with an offer to restart production of OV-10 Bronco. There are many other proposals as well, such as the Piper PA-48 Enforcer (a modern P51 Mustang)

Commentators often cite the Vietnam era Skyraider as the perfect CAS aircraft and make the extrapolation that a modern era Skyraider is what is needed in the skies of Afghanistan. As our previous article by Richard Stockley correctly highlighted, the Skyraider was withdrawn in the face of first-generation man-portable air defence missiles.

The revival of turboprop combat aircraft seems to boil down to three arguments;

  1. Fast jets aren’t that good for close air support, armed ISTAR or any of the other missions required in counter-insurgency operations where air superiority is a given.
  2. Fast jets are too expensive and sophisticated to provide Close Air Support in counter-insurgency operations as characterised by Afghanistan and given the likelihood of being engaged in similar operations in the coming decades the cost argument is a no brainer.
  3. Fast jets are too complex for emerging air forces that we can mentor.

None of these is arguments for turboprop aircraft but arguments against fast jets; it just so happens that the turboprop seems to offer an antidote for the ills of fast jets.

Fast Jets are no good at CAS/COIN

It is probably fair to say that Western air forces have concentrated on the exercise of airpower as a separate strategic stream to ground and naval power with strike, interdiction, air superiority, ISR (intelligence, surveillance, reconnaissance) and air transport missions shaping both doctrine and equipment. Mission over the Balkans and Iraq has confirmed that the RAF and USAF have these capabilities in spades.

The nature of ground combat, particularly in Afghanistan, dictates the use of light forces with little armour and a distributed enemy. It is primarily a conflict of light infantry. To compensate for the lack of numbers the western forces in Afghanistan rely completely on indirect fires, mortars, artillery and close air support.

Close air support whilst available in the RAF and USAF at the beginning of the conflict was not as well practised and only after several UOR’s has the RAF been able to provide such close air support as it does now.

One of the arguments driving the Turboprop CAS/COIN bandwagon is that fast jets are simply too fast to provide their pilots with sufficient situational awareness to provide an effective and safe support to troops in contact.

With the advent of improving tactics, techniques and procedures, coupled with the new capabilities offered by the latest generation of targeting pods where the forward air controller can actively cue weapons or see the same information as the pilot, this argument simply disappears.

Whilst it might have been true in Vietnam it is not true in Afghanistan.

Advocates of the Turboprop CAS aircraft point to better endurance but whilst this might be true, crucially, they fail to recognise the advantages that speed brings. Afghanistan is a huge place and to respond to a ‘Troops in Contact’ request for close air support the aircraft either has to be near or step on the gas to get there quickly. Time to get on the station will be significantly higher in a turboprop as well. Turboprops may be able to be based closer to operational areas and this may offset this to some extent but will require operations, maintenance and logistics to be equally distributed, costing more.

Fast jets can carry a massive load and in practice, this means a range of weapons, all available on a single aircraft that the forward air controller can choose to deploy based on the prevailing conditions. Turboprops do not have this high load capacity and would therefore have to be more numerous, they do not have the speed, so again, would have to be more numerous to cover the same area.

Fast jets are not restricted by weather conditions like small turboprops and can be refuelled in mid-air to extend the duration of a sortie or time on station.

Speed has its disadvantages but in addition to being able to respond quickly and cover a large area, it also provides safety. Although the air threat in Afghanistan is generally low that does not mean it is completely safe. Close examination of pictures of some aircraft operating in theatre will reveal air to air missiles are often carried, to counter the threat of an Iranian incursion. The Iranians have shown their willingness to take hostages as amply demonstrated by the RN/RM HMS Cornwall incident and a defenceless aircraft that they claimed had incurred into their airspace would be easy to coerce.

Ground fires are a significant danger; all aircraft operating in theatre is fitted with expensive but effective defensive aids against the man-portable ground to air missiles that the Taleban might obtain from sponsor nations and when operating at low-level automatic cannon or machine gun fire is a very serious threat.

A high-speed aircraft can transit danger zones quickly, unlike a slower turboprop which would remain in the threat zone for longer or simply not enter them in the first place which would limit effectiveness or mean aircraft and aircrew losses.

Finally, an unglamorous but absolutely essential activity that is carried out by fast jets is the show of force/show of presence that is used to deter ground elements or influence their actions. If one has ever seen these in action they are very effective, a turboprop, however cheap, is not going to have the same effect.

Close air support is not the only mission required in counter-insurgency air operations.

Afghanistan has also seen an explosion in the demand for imagery and other visual/non-visual information. This has been provided by manned aircraft but is largely fulfilled by Unmanned Air Systems (UAS) such as the UK’s Predator’s, Desert Hawks and Hermes 450s

Whilst of undoubted utility, UAS’s have a couple of big problems, situational awareness and bandwidth requirements.

Because the UAS operator looks at the world around them through an electro-optical sensor it can be compared to looking through a drinking straw or telescope. Wide-angle, peripheral vision is not available and whilst work is underway to address this issue it remains a significant problem.

Although the bandwidth used to control the flight of a UAS is quite modest and most new systems have some degree of autonomy which means they don’t need to be ‘piloted’ but ‘directed’ the raw sensor feed has to be transmitted as-is. Because no onboard analysis takes place by a skilled imagery analyst the bandwidth requirements are significant. This a difficult issue because the bandwidth available is limited by power restrictions, availability of secure bandwidth and plain old physics. Full motion video, even with advanced compression and only a medium resolution can require up to 20Mb/s, synthetic aperture radar, approximately 50Mb/s. Given that BOWMAN gets by with less than 10kbs one can begin to appreciate the scale of the problem. The demand is increasing at a fast pace.

A simple way to visualise the problem is showing your friends those holiday pictures. Of course, they are not interested in the vast majority of your pictures so you sort them and create a slideshow with only the best images. If you made your friends sit through all 3,675 images on your memory stick they would not be best pleased.

Imagery analysis, therefore, takes data and provides information.

If this analysis takes place on the ground then logic dictates that the analyst has to look through all your holiday snaps and he gets these via a saturated satellite link.

Put the analyst on the same platform that is capturing the imagery and you dramatically reduce the need for bandwidth as one only needs to transmit the edited highlights. Arm that platform and the response times to enable that information to be acted upon opportunistically is also reduced.

Weather is also a significant constraining factor on UAS’s which would be magnified greatly if future operations were out of dry and sunny places.

These constraints lead to the idea of Armed ISR aircraft.

Because there is less need in the armed ISR role for fast response, hard manoeuvring and low-level operation the disadvantages of a turboprop become diminished so the argument for this type of aircraft becomes much stronger. The RAF has recently started taking delivery of the Beechcraft Super King Air 350 based Shadow R1 ISR aircraft to supplement UAS’s. It would seem a relatively simple task to arm them with Hellfire or CRV-7 rocket pods to enable them to provide a short reaction time attack based on their own gathered intelligence.

Not CAS but armed ISR, they are completely different missions and have completely different requirements.

Fast Jets are too expensive

Maintenance requirements for fast jets are higher than for simple turboprops but this fails to take into account the effect of introducing a new airframe into an already stretched logistics, maintenance and training stream, all this would add up very fast.

Because one would need many more aircraft the spares holding would have to be vastly increased.

The costs of aircrew would also be significant, probably greater than any cost savings.

We already have Tornado and Typhoon, adding significant numbers of Super Tucano’s is not going to make the Typhoon and Tornado fleet any cheaper in the short term.

One fly in the ointment for using fast jets for intensive COIN/CAS work is that if airframe hours. Modern fast jets were simply not designed for sustained high tempo operations and are currently chewing through their airframe hours at a prodigious rate. This is bad from an airframe fatigue viewpoint and means that individual aircraft will likely have to be withdrawn from service far earlier than planned. The RAF for example, have recently started studies to examine options for extending the airframe life of the Typhoon, no doubt prompted by the reduced number of Tranche 3 aircraft they will be receiving. From a cost perspective, using a lower-cost alternative to marshal and eke out airframe hours on more expensive types is a strong argument.

However, we think this is an argument for more fast jets or even a new build close air support aircraft that has the advantages of a fast jet at a reasonable price and none of the numerous disadvantages of a turboprop aircraft, maybe a new build two-seat A10C (subject of a later post)

Fast Jets are too complex for indigenous air forces

It is undoubtedly true that something like an F15 or Typhoon is out of the reach of, for example, the Afghan National Army Air Corps who are still working up to operating basic transport aircraft and helicopters. The Iraqi’s have been operating King Airs and Grand Caravan’s in the armed ISR role with some success but when asked if they wanted to buy into the new cheap CAS/COIN aircraft, their answer was, no thanks, can we have some F16’s instead.

This is perhaps the greatest argument in favour of a cheap CAS/COIN aircraft, operating them in order to mentor indigenous air forces and help them transition to the more capable jet types but we must recognise the limitations and concentrate on skills and training because Close Air Support of troops in contact requires the highest level of skill.


Propeller based close air support was supplanted by fast jets for a very good reason, effectiveness and survivability. Nothing in any of the proposed solutions for so-called low-cost CAS/COIN aircraft convinces us that these reasons have changed.

Nothing beats fast jets for payload, endurance, versatility and effectiveness.


However, they are expensive, really…

The idea of replacing a few expensive fast jets with more numerous cheaper types (numerous because as we have described, they are simply not as effective) does seem on the surface to offer a cheaper solution but this argument more often than not restricts itself to making a one to one comparison without any context. Of course, a Super Tucano is going to be cheaper to operate and buy than Typhoon in a one to one, but as we have shown, one would need many Super Tucano’s to do the job of a single Typhoon and that is just capital cost; the really expensive element is support costs. Spares, maintenance teams and the most expensive element of all, aircrew, would produce a situation that we believe would increase overall costs yet offer nothing more in terms of effect; in fact, it would have a lesser effect.


Fast jets are too expensive and complex for indigenous or emerging air forces so the argument for a cheap CAS/COIN aircraft is strong here


2-1 in favour of the fast jet.

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