Radial engines arent the issue in terms of cost but in terms of reliability and power. As an example, the Merlin used on the Bearcat weighs about a 1250kg and gives about 2200HP(so far there is no current off the shelf solution available for a powerful piston engine as they all went out of fashion versus turboprops)in the low level environment you are referring to.
The engine on the Bearcat (PW R-2800) had two layers of radials, this is known to cause heating issues as the second layer is insufficiently cooled. The bearcat ws. There are Chinese, Polish and Ukrainian solutions, for instance the HS-5 which can easily be uprated to 1500 hp (depending on the variant, this series of Soviet / Chinese / Eastern European radial engines give 900 - 1200 hp as is).
China in the 1990s stopped producing this engine but is known to have all the tooling. One could potentially by the tooling and blue prints from China / Ukraine / Poland, all of whom still produce parts for the IL-2 and related crop dusters.
We don't really need a very high thrust to weight ratio as its a simple CAS aircraft, or so I would argue. Nor do we need a heavy weapons load, with the presence of precision munitions in the class of Brimstone, Cirit.
Moreover, at this point it is actually cheaper to procure a PT-6A with its associated logistics instead of a radial. After all, the idea is to look at something realistic, not just aircraft cost but an actual serious cost of program R&D that could actually be doable rather than what-ifs.
The reason I want to avoid a PT-6A or related turbo props are the costs, not only of acquisition but of maintenance, which is complex and expensive, specially if you look at the hot section issues.
For instance, in the civilian market, a comparable aircraft with a piston engine versus a P&W turboprop usually costs twice the amount - in one instance, it was $1 million with the piston engine, very similar in capability aircraft with a turboprop was twice the cost at $2 million.
Here is an interesting technical bit - the advantage of the turboprop is above 100 FL. At loiter and below 5000 feet there is no meaningful fuel efficiency difference, and that is against simpler pistons, not the radials where the gap is even narrower.
While the radial would take more frequent maintenance, it costs a lot less and can most often be repaired on the field by mechanics. Something not possible for turboprops.
The reason I support radials, in summary are:
1. much lower costs of acquisition and maintenance (remember my price point for the product)
2. considerably easier to maintain
3. Rugged and can be maintained by lower skilled mechanics
4. Gives very comparable performances in real-world scenarios and not theoretical high altitude cruise where turboprops excel and win the powerpoint game.
However, if I had to compromise to make the design a reality, I'd be happy to let go of this requirement. But it is intrinsically tied to the low cost - large scale strategy that I'm looking at. $4 to $7 million per plane, 100 units. moment the price goes up, quantity comes down, destroying economies of scale, further increasing the price, which further decreases units, and the vicious spiral continues.
Moving to enlisted pilots, the issue has been debated by the USAF as well. You cannot have ill trained monkeys in the air so the requisite costs of flight training come in which then put the same strain on economics. The PAF currently has a pilot to aircraft ratio of about 1:1.5 so it makes no sense to put additional "Half-pilots" into what is essentially a near suicidal mission just to halve JF-17 costs.
CAS is all about practice. And there is no reason enlisted pilots cannot perform. For a long time in the 2000s, the best Predator pilot was a 19 year old who had no USAF training, let alone officer training. You don't need an officer to be a tank driver, why have one for a simple rugged CAS aircraft?
Bahrain takes the CAS cake in Gulf competitions with their F-5, not because their pilots are amazing, or that their aircraft is - its simply practicing one thing alone - CAS is all those F-5 pilots practice. So, I think that having enlisted pilots focused on a single role would do amazing wonders and surprise us all.
USAF has become a fighter pilot trade union and many within mourn this. It is what kept them from adapting to UAVs properly until the CIA showed them the way. Even today they are grudgingly accepting UAVs and doing it in a very wrong-footed way. Do we really need the USAF to be the model?
Also notice how Marine pilots do so much better at CAS because of their better frequency, and how they do so much worse at A2A. Leaving CAS to a specialized group of enlisted pilots will give you not only excellent CAS, but it will help PAF pilots do their A2A and SEAD / DEAD job better.
PAF has always had a high pilot to aircraft ratio, this is to maintain tempo of operations during war, and because aircraft from friendly countries / reserves are expected. Its not an unplanned surplus of pilots. These pilots are also very expensive to train.
So, if you added 100 CAS aircraft to the mix, PAF would need to plan for that and add 150 pilots. My solution takes PAF out of the equation rather than forcing it to expend valuable resources on a secondary mission. And it does so at a very good cost / fast pace. It also allows the PA to integrate the pilot training and mix it with its army training - just like the US Marines, allowing the pilot to understand ground operations better. Something valuable for CAS.
A helicopter isnt just an attack platform, its ability to land right behind the battlefield to rearm and refuel, along with the ability to hide and evade is unmatched by any fixed wing even one capable of 150 degrees a second since a fixed wing aircraft cannot duck behind a hill and stay there.
This has been an unrealized hope as mostly, it has not been logistically possible to arm and refuel helicopters just behind the battlefield. Because of their complexity and other logistics issues, attack helicopters have most frequently been based from FABs alongside fixed wing.
However, with the SABA-type, you can actually base these aircrafts alongside the moving Corps HQ. Because of their simple, rugged nature, their STOL and rough field performance, and their long loiter time, they can be more easily integrated than most aircraft out there with the exception of UAVs.
While a helicopter can duck behind a hill, that ability sacrifices kinetic performance. Meaning in the mode of hiding behind a hill or trees, a helicopter actually has very little kinetic energy. It can easily be seen by airborne assets because of those large rotating blades. With the advent of thermal sights, hiding behind a clump of trees has become meaningless.
The SOP of CAS is to stay low, fly fast, pop up from a flank at range, deliver munitions, duck back low and get out. The SABA-inspired can do this perfectly well. Niche issues exists where the attack helicopter does better, but that's the niche. The bread and butter is covered best by the SABA-type fixed wing.
I still maintain that your proposal is a nice what if clean sheet idea that will take a reasonable investment much like the AHLRAC is for Paramount but could recoup its costs with some rich Arab nation facing lots of technicals or a highly advanced airforce holding air superiority over the frontline... ironically, the Indian Air Force is more of a candidate for this type of asset versus their truckload that is the Tejas and would suit their low intensity eastern fronts and a western front scenario whenever they eventually knock or ground the PAF out of the sky and start picking out whatever remains of the PA regrouping.
But in the limited week long scenario of the PAF trying to force a detente against a much more powerful and equally well trained IAF; I will disagree on both the utility and cost effectiveness of this concept.
Thanks for the assessment. Its always good to have a solid assessment even if one doesn't like its conclusion. I think the IAF squadron strength has seriously suffered and is likely to continue to be an issue going forward. PAF has closed the gap in leaps and bounds.
It can close the gap even further if it:
1. Invests in UCAV strike platforms
2. Looks at SEAD / DEAD more innovatively (Harpy)
3. Creates a better IADS
4. Focuses on its core mission of knocking out IAF
For #4 to happen, it needs to spend maximum time training on those competencies and not on CAS. This is where the SABA type helps. It also helps because it diverts and distracts IAF, who now have to spend resources and its fighters to try to hunt down decentralized, terrain hugging CAS aircraft
while trying to deal with the very strong PAF.
With the IA mainly focusing on creating massive concentrations of its forces, a CAS aircraft can do real damage in just a few passes. Just a few canisters of cluster munition can cause havoc. Deployed behind PA armored divisions, they would hardly need to even enter Indian airspace to cause such damage.
There are a host of other auxillary benefits - like hunting down enemy artillery batteries. Or acting as a wifi hub to the ground forces. Or recon. Or jamming enemy comms. Or taking out enemy UAVs and helicopters.
100 CAS aircraft at the price of 500 million to 700 million. Built locally with the ability to run production during war. Compare that to any other weapons purchase. Like the 1.5 Billion USD for 30 odd T-129s...
The proposal closely mirrors the 80 - 20 rule - 80 percent of the capability costs 20 percent of the cost. I'm proposing that 80% in a situation where there is no other choice other than 1) expensive foreign import in insignificant numbers and 2) superweapons that seek that 90% or 100% of the capability and sacrifices reality to the detriment of all.