Armchair
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With US shutting out AH-1Z purchases, and the chronic lack of armed drones, PAA is facing a challenge in meeting contemporary capability needs. A handful of drones imported from abroad and some others that aren't able to be armed meaningfully leaves, the Pakistan Army Aviation can be revamped and its capabilities multiplied with a locally produced drone and CAS aircraft.
The problem however is costs. The cost of an attack helicopter is between 25 million to 40 million USD. CAS aircraft such as the Super Tucano are about 10 million USD. JF-17s are precious, and @Signalian suggests F-7Ps being relegated to PAA to meet this dire need.
However, while the suggestion has its merits, the downside is F-7Ps are too fast to provide meaningful CAS and are hard to maintain, costly to keep and their build quality is poor meaning they are near the end of their lives.
I am proposing here a simple yet radical solution that does not follow conventional Western doctrine. The biggest cost of building a local CAS aircraft / Drone are in its:
1. Engine
2. Electronics
3. Armaments
4. Airframe
Engines are expensive to import, even if Kamra now has the ability to fabricate airframes, and some level of capability exists for armament.
Turboprop engines are expensive and difficult to build, in capability areas not available in Pakistan, and available only in a handful of countries. Instead, I am proposing one uses a two-stroke engine combined with a pulse jet.
Both of these are simple to make (can be made in a garage by hobbyists), and yet, when combined they are effective.
Advantages and disadvantages of a two-stroke engine: Simple to build and providing reasonable thrust to weight ratio, two-stroke engines' weakness is its relatively poor fuel efficiency - a good part of the fuel flows out unused.
Yet, this unburnt fuel can be channeled to a pulse jet engine which can then use the same to generate thrust.
Advantages and disadvantages of a pulse jet engine: Poor fuel consumption (as with all jet engines) and less durability. Advantage: simple to build and when combined with a two-stroke, the combined system gives greater efficiency of thrust than either system alone.
Here is an example of a two-stroke engine used in rc planes
This particular model can be sand-casted easily at any basic facility. It generates 13 HP
If one enlarges the same, it could be made to generate 50 HP.
Here is how to build pulse jets, originally used by Nazi Germany, including to make night intercept fighters at one point in the war. http://www.pulse-jets.com/
They are often built in home garages by hobbyists. Modern designs such as using a petal arrangement and using roofing paint for combustion interior, increases the reliability and effectiveness of pulse jets.
If in a hybrid arrangement, 33% of the thrust is generated by the two-stroke engine and 66% by the pulse jet, one can come up with an aircraft / drone that will:
1. cost pennies to the dollar. Even CAS aircraft costing as little as 100,000 USD
2. Allow Pakistan to build an aircraft / drone 100% at home
3. Allow mass production so Pakistan can build drones / CAS aircraft in a hurry during a war.
With the latest result from Turkish drones in Idlib, the effectiveness of CAS and drones become clear and a pressing need. Being able to produce large numbers of them would allow Pakistan to easily overwhelm a larger enemy.
Opportunities come for those who are willing to see them.
@Bilal Khan (Quwa) @Signalian @Bilal Khan 777 @MastanKhan @FuturePAF @messiach
FAQs
But why no other countries are doing it?
Ans: Most countries follow the West in whatever they do. The West (and other major powers such as China) does not need a low cost solution that cannot give them long range and technological superiority. This is why both two-stroke aircraft engines and pulse jets where abandoned in favor of jet engines and turbofans. However, since these latter technologies are outside Pak's reach, this solution suits Pakistan's needs.
Following the crowd and taking the West as our tech god is not a methodology to success always.
Your cost estimates are so low. How is that possible? Modern engines cost a lot more than this.
Ans. Precisely. "modern" engines do, of the type that falls under jets, turbofans, turboprops and even four-stroke gasoline engines. These two engines given are the simplest, easiest to build engines in the world. Pulse jets largely a Nazi technology, while two-stroke aircraft engines were last put on a fighter by the UK. No one apparently thought yet of bringing them together. No one thought how such a simple solution does not require the materials, metallurgy and mechanical complexity of today's engines. Not because they are dumb, but because they walked down a different road suitable for their country's benefit (power projection, high MTBF, best fuel economy).
Have you built these yourself? Do you have a proof of concept?
Ans. No I don't. But if you look around online you can find these done by hobbyists worldwide. Including a fellow in New Zealand who says his pulse jets can be turned into cruise missiles at a fraction of the cost.
How much do you estimate a CAS aircraft to cost? A drone?
Ans. Anywhere between 100,000 to 1 million USD, depending on what exactly the spec requirement is. As for drones, anywhere from 5,000 to 50,000 USD, again depending on specs.
The engine size in the Aliexpress rc model is pretty small. How can one enlarge it?
Ans. Making anything small is a lot harder than making them bigger. Simply taking the engine and making a bigger version is one way. Another way adopted by DLE and other engine manufacturers is to increase the number of cylinders. The example shown is for a two cylinder model. There are models with 4 cylinders. In theory, we could thus not only increase the size but increase the number of cylinders. Such engines are not new, but existed in aircraft before the jet age, although most (not all) were four-stroke engines back then.
The problem however is costs. The cost of an attack helicopter is between 25 million to 40 million USD. CAS aircraft such as the Super Tucano are about 10 million USD. JF-17s are precious, and @Signalian suggests F-7Ps being relegated to PAA to meet this dire need.
However, while the suggestion has its merits, the downside is F-7Ps are too fast to provide meaningful CAS and are hard to maintain, costly to keep and their build quality is poor meaning they are near the end of their lives.
I am proposing here a simple yet radical solution that does not follow conventional Western doctrine. The biggest cost of building a local CAS aircraft / Drone are in its:
1. Engine
2. Electronics
3. Armaments
4. Airframe
Engines are expensive to import, even if Kamra now has the ability to fabricate airframes, and some level of capability exists for armament.
Turboprop engines are expensive and difficult to build, in capability areas not available in Pakistan, and available only in a handful of countries. Instead, I am proposing one uses a two-stroke engine combined with a pulse jet.
Both of these are simple to make (can be made in a garage by hobbyists), and yet, when combined they are effective.
Advantages and disadvantages of a two-stroke engine: Simple to build and providing reasonable thrust to weight ratio, two-stroke engines' weakness is its relatively poor fuel efficiency - a good part of the fuel flows out unused.
Yet, this unburnt fuel can be channeled to a pulse jet engine which can then use the same to generate thrust.
Advantages and disadvantages of a pulse jet engine: Poor fuel consumption (as with all jet engines) and less durability. Advantage: simple to build and when combined with a two-stroke, the combined system gives greater efficiency of thrust than either system alone.
Here is an example of a two-stroke engine used in rc planes
This particular model can be sand-casted easily at any basic facility. It generates 13 HP
If one enlarges the same, it could be made to generate 50 HP.
Here is how to build pulse jets, originally used by Nazi Germany, including to make night intercept fighters at one point in the war. http://www.pulse-jets.com/
They are often built in home garages by hobbyists. Modern designs such as using a petal arrangement and using roofing paint for combustion interior, increases the reliability and effectiveness of pulse jets.
If in a hybrid arrangement, 33% of the thrust is generated by the two-stroke engine and 66% by the pulse jet, one can come up with an aircraft / drone that will:
1. cost pennies to the dollar. Even CAS aircraft costing as little as 100,000 USD
2. Allow Pakistan to build an aircraft / drone 100% at home
3. Allow mass production so Pakistan can build drones / CAS aircraft in a hurry during a war.
With the latest result from Turkish drones in Idlib, the effectiveness of CAS and drones become clear and a pressing need. Being able to produce large numbers of them would allow Pakistan to easily overwhelm a larger enemy.
Opportunities come for those who are willing to see them.
@Bilal Khan (Quwa) @Signalian @Bilal Khan 777 @MastanKhan @FuturePAF @messiach
FAQs
But why no other countries are doing it?
Ans: Most countries follow the West in whatever they do. The West (and other major powers such as China) does not need a low cost solution that cannot give them long range and technological superiority. This is why both two-stroke aircraft engines and pulse jets where abandoned in favor of jet engines and turbofans. However, since these latter technologies are outside Pak's reach, this solution suits Pakistan's needs.
Following the crowd and taking the West as our tech god is not a methodology to success always.
Your cost estimates are so low. How is that possible? Modern engines cost a lot more than this.
Ans. Precisely. "modern" engines do, of the type that falls under jets, turbofans, turboprops and even four-stroke gasoline engines. These two engines given are the simplest, easiest to build engines in the world. Pulse jets largely a Nazi technology, while two-stroke aircraft engines were last put on a fighter by the UK. No one apparently thought yet of bringing them together. No one thought how such a simple solution does not require the materials, metallurgy and mechanical complexity of today's engines. Not because they are dumb, but because they walked down a different road suitable for their country's benefit (power projection, high MTBF, best fuel economy).
Have you built these yourself? Do you have a proof of concept?
Ans. No I don't. But if you look around online you can find these done by hobbyists worldwide. Including a fellow in New Zealand who says his pulse jets can be turned into cruise missiles at a fraction of the cost.
How much do you estimate a CAS aircraft to cost? A drone?
Ans. Anywhere between 100,000 to 1 million USD, depending on what exactly the spec requirement is. As for drones, anywhere from 5,000 to 50,000 USD, again depending on specs.
The engine size in the Aliexpress rc model is pretty small. How can one enlarge it?
Ans. Making anything small is a lot harder than making them bigger. Simply taking the engine and making a bigger version is one way. Another way adopted by DLE and other engine manufacturers is to increase the number of cylinders. The example shown is for a two cylinder model. There are models with 4 cylinders. In theory, we could thus not only increase the size but increase the number of cylinders. Such engines are not new, but existed in aircraft before the jet age, although most (not all) were four-stroke engines back then.