"Air-breathing TSTO TD to have first flight later this decade!"
If he is talking about about an actual vehicle that will go to space? At this point the a regular TSTO is all that's looking realistic by end of the decade. A TSTO with turbojet-ramjet-scramjet is pro ultra max hopium overdoze.
No it's not an overdose, ISRO doesn't give any fake promises, they will announce any project only if they have matured tech. Before Gaganyaan is announced ,they proved all the required tech like reentry , crew module, ECLSS, Launch Vehicle and CES. Similarly for Air breathing TSTO, they already proved the basic tech like Dual Mode Ramjet (in 2016) , Thermal management, Aerodynamics & GNC using RLV ( in 2016) and they are gonna improve this in coming years using RLV-LEX, RLV-ORV & HAVA. The reasons for delay in ISRO projects is because of lack of funding not lack of technology.
Will be used on Ghatak stealth UCAV (the bigger version of SWiFT which is to be ready by 2025).
Tejas Mk2 and AMCA will require new engine to be developed by GTRE.
ISRO's Scramjet is actually a Dual Mode Ramjet. They tested it in 2016 using a Rohini sounding rocket called ATV-2. Don't take much from those renders.
No it's not an overdose, ISRO doesn't give any fake promises, they will announce any project only if they have matured tech. Before Gaganyaan is announced ,they proved all the required tech like reentry , crew module, ECLSS, Launch Vehicle and CES. Similarly for Air breathing TSTO, they already proved the basic tech like Dual Mode Ramjet (in 2016) , Thermal management, Aerodynamics & GNC using RLV ( in 2016) and they are gonna improve this in coming years using RLV-LEX, RLV-ORV & HAVA. The reasons for delay in ISRO projects is because of lack of funding not lack of technology.
One thing suddenly struck me, maybe them putting a rough date on AB-TSTO has to do with the recent progress in Kaveri engine? I mean without Kaveri or another indigenous engine, AB-TSTO will never fly. And before this presentation, they never gave a date for the AB-TSTO. Maybe they really are serious about this date. They would have been liaising with GTRE, waiting for GTRE to produce a viable engine for AB-TSTO. Only when an engine became possible did they put out a rough date on AB-TSTO
We could have two ways,1 by PDE or 2 by conversion
For pulse detonation engine you need air of high pressure,Otherwise it will be too heavy For the pressurized air you need a compressor and for compressor you need power,It may be suited for short distance one way travel like hypersonic missiles,but it will not be suitable for a high speed aircraft
Better is
We can convert a subsonic capable turbofan into a high supersonic one With proper shock cone and shock boundary layer interaction controls,A rotating detonation combustion chamber in the engines will pave the way for future manned hypersonic fighter jets because it is a constant volume process and in constant volume process your get higher amount of heat in the same temperature regime
Will be used on Ghatak stealth UCAV (the bigger version of SWiFT which is to be ready by 2025).
Tejas Mk2 and AMCA will require new engine to be developed by GTRE.
One thing suddenly struck me, maybe them putting a rough date on AB-TSTO has to do with the recent progress in Kaveri engine? I mean without Kaveri or another indigenous engine, AB-TSTO will never fly. And before this presentation, they never gave a date for the AB-TSTO. Maybe they really are serious about this date. They would have been liaising with GTRE, waiting for GTRE to produce a viable engine for AB-TSTO. Only when an engine became possible did they put out a rough date on AB-TSTO
Only missing link in AB-TSTO is TurboFan.Except this ,ISRO can master all other tech easily. They have the required Infrastructure including Hypersonic wind tunnels and manpower for that. Only Kaveri or its derivative can fullfill that role. No other country will give us their TurboFan engine for our Hypersonic aircraft program. It should be an Indigenous engine.Hence AB-TSTO is directly linked to it & your guess that ISRO working with GTRE may be actually true. Believe me, if Mudi baba gives Gaganyaan level funding & support for Hypersonic aircraft, they will rollout it in less than 5 years. That's why I said we are unnecessarily wasting 1.5 lac crores on Mlecchas , we should stop funding them and divert that money to ISRO, DRDO and other R&D institutes
Will be used on Ghatak stealth UCAV (the bigger version of SWiFT which is to be ready by 2025).
Tejas Mk2 and AMCA will require new engine to be developed by GTRE.
One thing suddenly struck me, maybe them putting a rough date on AB-TSTO has to do with the recent progress in Kaveri engine? I mean without Kaveri or another indigenous engine, AB-TSTO will never fly. And before this presentation, they never gave a date for the AB-TSTO. Maybe they really are serious about this date. They would have been liaising with GTRE, waiting for GTRE to produce a viable engine for AB-TSTO. Only when an engine became possible did they put out a rough date on AB-TSTO
Yes. I know, it sounds almost impossible given current state of affairs, but I'd never seen a timeline on the Air-breathing TSTO before, I just assumed it would be attempted after the RLV-TD based TSTO succeeds in late 2020s. So somewhere in the late 2030s or early 2040s maybe. Which is why this addtion of a "later this decade" surprised me. Even if it is for a TD.
But the building blocks are meant to be in place by around 2025-27. So why not? Its just a TD, not the full vehicle.
But then I saw the "turbo-ramjet" they are planning, and now even I am questioning that date. I thought they would go with a simple turbojet + dmrj. Turboramjet is going to introduce unwanted complexities. At this stage, our DMRJ and turbojet are at similar levels of maturity. Turboramjet is something that (as far as I know) is on a ppt, not even on the drawing board yet.
I have not watched the latest video, but if it is the same specs as the one released a some time last year or so, then it appalling an ISRO official can claim they can do it with in the next 10 years.
Ok so lets breakdown this vehicle or at least the first stage that is supposed to be reusable:
1. It is going to be an unmanned aircraft that is going weigh (MTOW) around 2/3 of a Concord or B1 bomber i.e. it's going to be approximately 10 times heavier than the heaviest aircraft we have designed till date (Tejas or Maruth).
2. The first phase is going to be a turbo-ramjet that will take it to Mach 6. And what is the fastest that a (re-usable) air breathing aircraft has gone? AFAIK it is the SR-71 (or one of its cousins) at Mach ~3.2. So essentially ISRO will build a vehicle that will reach almost twice the speed of the Blackbird?
3. And then the scramjet will kick in to take it from M6 to M9. Now what is the biggest scramjet vehicle that has ever been flown by any one? Also has anyone managed to build a scramjet engine/vehicle that has actually be re-used even once?
4. If that was not complex enough, the first stage actually then needs a conventional rocket to take it to M12?
And all this is going to happen with in the next 10 years? With ISRO's budget?
And here's the real kicker, after doing all this they are claiming a payload fraction of less than half of what Space X Falcon 9 does TODAY with reusable first stage using conventional Kerolox rockets (1.5% vs >3%). If they instead take the metholox engine that they are developing and cluster it in 2 stages, with first stage landing back vertically i.e. a mini Falcon 9 they will get a simpler, cheaper, better performant AND realistically feasible launch system than this pie in the sky.
IMO this is purely a "science project", and not a very promising one at that. It will remain on a PPT, folks who are getting excited will only get KLPD out of this.
I have not watched the latest video, but if it is the same specs as the one released a some time last year or so, then it appalling an ISRO official can claim they can do it with in the next 10 years.
Ok so lets breakdown this vehicle or at least the first stage that is supposed to be reusable:
1. It is going to be an unmanned aircraft that is going weigh (MTOW) around 2/3 of a Concord or B1 bomber i.e. it's going to be approximately 10 times heavier than the heaviest aircraft we have designed till date (Tejas or Maruth).
2. The first phase is going to be a turbo-ramjet that will take it to Mach 6. And what is the fastest that a (re-usable) air breathing aircraft has gone? AFAIK it is the SR-71 (or one of its cousins) at Mach ~3.2. So essentially ISRO will build a vehicle that will reach almost twice the speed of the Blackbird?
3. And then the scramjet will kick in to take it from M6 to M9. Now what is the biggest scramjet vehicle that has ever been flown by any one? Also has anyone managed to build a scramjet engine/vehicle that has actually be re-used even once?
4. If that was not complex enough, the first stage actually then needs a conventional rocket to take it to M12?
And all this is going to happen with in the next 10 years? With ISRO's budget?
And here's the real kicker, after doing all this they are claiming a payload fraction of less than half of what Space X Falcon 9 does TODAY with reusable first stage using conventional Kerolox rockets (1.5% vs >3%). If they instead take the metholox engine that they are developing and cluster it in 2 stages, with first stage landing back vertically i.e. a mini Falcon 9 they will get a simpler, cheaper, better performant AND realistically feasible launch system than this pie in the sky.
IMO this is purely a "science project", and not a very promising one at that. It will remain on a PPT, folks who are getting excited will only get KLPD out of this.
I have not watched the latest video, but if it is the same specs as the one released a some time last year or so, then it appalling an ISRO official can claim they can do it with in the next 10 years.
Ok so lets breakdown this vehicle or at least the first stage that is supposed to be reusable:
1. It is going to be an unmanned aircraft that is going weigh (MTOW) around 2/3 of a Concord or B1 bomber i.e. it's going to be approximately 10 times heavier than the heaviest aircraft we have designed till date (Tejas or Maruth).
2. The first phase is going to be a turbo-ramjet that will take it to Mach 6. And what is the fastest that a (re-usable) air breathing aircraft has gone? AFAIK it is the SR-71 (or one of its cousins) at Mach ~3.2. So essentially ISRO will build a vehicle that will reach almost twice the speed of the Blackbird?
3. And then the scramjet will kick in to take it from M6 to M9. Now what is the biggest scramjet vehicle that has ever been flown by any one? Also has anyone managed to build a scramjet engine/vehicle that has actually be re-used even once?
4. If that was not complex enough, the first stage actually then needs a conventional rocket to take it to M12?
And all this is going to happen with in the next 10 years? With ISRO's budget?
And here's the real kicker, after doing all this they are claiming a payload fraction of less than half of what Space X Falcon 9 does TODAY with reusable first stage using conventional Kerolox rockets (1.5% vs >3%). If they instead take the metholox engine that they are developing and cluster it in 2 stages, with first stage landing back vertically i.e. a mini Falcon 9 they will get a simpler, cheaper, better performant AND realistically feasible launch system than this pie in the sky.
IMO this is purely a "science project", and not a very promising one at that. It will remain on a PPT, folks who are getting excited will only get KLPD out of this.
If they go for a turboramjet, its going to take a lot more time. Compared to if they go for an afterburning turbojet+dmrj.
Sadly, they seem to be going for the former.
What is wrong with using turbojet+afterburner to get to Mach 1.8 and then going dmrj from there? A turboramjet will be complex enough to kill this project.
What is wrong with using turbojet+afterburner to get to Mach 1.8 and then going dmrj from there? A turboramjet will be complex enough to kill this project.
What is wrong with using turbojet+afterburner to get to Mach 1.8 and then going dmrj from there? A turboramjet will be complex enough to kill this project.
As far as I know, the transition between turbojet and ramjet modes in a turboramjet isn't a simple switch of the inlets, there are times when both are running together. That would introduce complex airflows and GTRE already has enough problems handling airflows in a conventional flow engine. If we go this route, it will be another long torturous development cycle, especially with the kind of funding we have.
