Ghatak and Rustom Indigenous UAV Programs

Some observations from the photo :

1. The new turbo-diesel engines have asymmetric intakes & a bolstered engine mount. The new engine is heavier & twice as powerful as the NPO Saturn 36MT used on the prototypes. With 2 engines the current drone has 4 times the power of the initial prototype.
2. The military wanted the drone to have 3000 km of range, 50k ft of service ceiling & a MTOW of 3 tons. With the 36MT the drone had a MTOW of ~2.15 tons & a weapon payload of 350 kg. The new engine will give it ~500-600 kg of weapon payload. The HELINA/Dhruvastra weighs around 45 kg & the SANT should be <70 kg. Theoretically the drone should be able to carry ~10 HELINA/Dhruvastra & >8 SANT missiles.
3. The new landing gear has also been integrated. Seems to be well designed, no visible sagging. The orange parts of the wing & tail are movable leading edge slats.
4. The orange parts of the fuselage are for housing the Synthetic Aperture Radars (SARs). There is one central large SAR & 2 smaller side mounted SARs.
5. When it enters service it is likely to be the largest drone with the military. No wonder they needed to develop an Automatic Takeoff & Landing System for this drone.

Somebody made this poster sometime back. Its pretty accurate :
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It's armed variant will have 220 hp engine wonder how much payload it can give.
 

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Excellent photos! Thx for posting.
Do we know yet if the test-bed incorporates a platypus-based exhaust system? Or is it still conventional for now? further, is that even a technology that is worked & validated upon a scaled test-bed, or do such systems get validated only on 1:1 prototypes?

Also, I understand that the antennas projecting out are currently to establish flight control laws? And that they would be embedded into the skin in subsequent iterations ? Very interesting indeed. Godspeed to the team, would be great to witness a production version flying alongside AMCA and Rafale by the 2030s.

Regards,
 
Do we know yet if the test-bed incorporates a platypus-based exhaust system? Or is it still conventional for now? further, is that even a technology that is worked & validated upon a scaled test-bed, or do such systems get validated only on 1:1 prototypes?
There was a competition in the DRDO for the design choice of a Low-Observable jet pipe. The result of that competition was that 2D jet pipes, which are more stealthier, were chosen to be used on more expensive assets like the Ghatak. Where as rounded chevron jet pipes were chosen for relatively cheaper expendable stealthy drones like the CATS Warrior.

The SWiFT is going to prove a smaller version of the 2D jet pipe & a large version is being prototyped to be integrated with the dry Kaveri. Jet pipe motion is how you achieve thrust vectoring which is a integral part of flight control laws. The entire purpose of SWiFt is to validate the flight control laws. You cannot do that without validating thrust vectoring.
Also, I understand that the antennas projecting out are currently to establish flight control laws?
The antennas are for data transmission, relay, GPS etc. They allow the users to control the SWiFT. They send critical flight data that can be used by scientists for validating the design of the drone. They receive signals from the GPS & also relay data from the EO sensors.
And that they would be embedded into the skin in subsequent iterations ?
Body flush antennas are a critical part of stealth design. There antennas will be body flushed at a later stage. We already have body flush antennas in use in many of our missiles. It is not a new or unfamiliar technology.
Program success depends on Kaveri engine. Production will not happen in this decade.
That's not true.

From the EoI that was published in January 2020 around 20 dry Kaveri engines will be made under the Limited Series Production (LSP) in within the next 7-8 years. After that the Full Scale Production (FSP) would start which will see the production of some 70-80 engines in the next 10-12 years.

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Within the LSP the initial 5 engines will be made by the GTRE from raw material stage to full integration & a selected Indian industry partner will get the know how & know why of the engine in that time. This phase will be the slowest phase of production run with one engine made at an interval of 3 months.

After the initial 5 engines are fabricated the selected industry partner will get complete responsibility of the engine production, from raw material to final integration. Of course the tools, instruments, production & testing infrastructure etc. will be provided for by the GTRE. GTRE will act as an auditor to the production agency. In this phase of the LSP 15 engines will be made each at an interval of 2 months. That would conclude the 20 engines LSP production run.

The production agency would also need to set up their own infra by the end of the LSP & get it certified. The FSP will happen at this new facility freeing up the GTRE's facilities. GTRE would of course remain involved with the Kaveri & try to bring in incremental improvements to the engine.

The biggest technological impediment to the dry Kaveri engine was the development of a distortion tolerant fan. That has been cleared before this EoI was published.
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The production plan seems pretty reasonable to be. Even if they don't meet their target of 20+ engines by 2030 entirely there should still be a good number of engines available for the Ghatak program.
 
There was a competition in the DRDO for the design choice of a Low-Observable jet pipe. The result of that competition was that 2D jet pipes, which are more stealthier, were chosen to be used on more expensive assets like the Ghatak. Where as rounded chevron jet pipes were chosen for relatively cheaper expendable stealthy drones like the CATS Warrior.

The SWiFT is going to prove a smaller version of the 2D jet pipe & a large version is being prototyped to be integrated with the dry Kaveri. Jet pipe motion is how you achieve thrust vectoring which is a integral part of flight control laws. The entire purpose of SWiFt is to validate the flight control laws. You cannot do that without validating thrust vectoring.

The antennas are for data transmission, relay, GPS etc. They allow the users to control the SWiFT. They send critical flight data that can be used by scientists for validating the design of the drone. They receive signals from the GPS & also relay data from the EO sensors.

Body flush antennas are a critical part of stealth design. There antennas will be body flushed at a later stage. We already have body flush antennas in use in many of our missiles. It is not a new or unfamiliar technology.

That's not true.

From the EoI that was published in January 2020 around 20 dry Kaveri engines will be made under the Limited Series Production (LSP) in within the next 7-8 years. After that the Full Scale Production (FSP) would start which will see the production of some 70-80 engines in the next 10-12 years.

View attachment 21614

Within the LSP the initial 5 engines will be made by the GTRE from raw material stage to full integration & a selected Indian industry partner will get the know how & know why of the engine in that time. This phase will be the slowest phase of production run with one engine made at an interval of 3 months.

After the initial 5 engines are fabricated the selected industry partner will get complete responsibility of the engine production, from raw material to final integration. Of course the tools, instruments, production & testing infrastructure etc. will be provided for by the GTRE. GTRE will act as an auditor to the production agency. In this phase of the LSP 15 engines will be made each at an interval of 2 months. That would conclude the 20 engines LSP production run.

The production agency would also need to set up their own infra by the end of the LSP & get it certified. The FSP will happen at this new facility freeing up the GTRE's facilities. GTRE would of course remain involved with the Kaveri & try to bring in incremental improvements to the engine.

The biggest technological impediment to the dry Kaveri engine was the development of a distortion tolerant fan. That has been cleared before this EoI was published.
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The production plan seems pretty reasonable to be. Even if they don't meet their target of 20+ engines by 2030 entirely there should still be a good number of engines available for the Ghatak program.
It is having fluidic thrust vectoring system with elliptical nozzle.
 
From the EoI that was published in January 2020 around 20 dry Kaveri engines will be made under the Limited Series Production (LSP) in within the next 7-8 years. After that the Full Scale Production (FSP) would start which will see the production of some 70-80 engines in the next 10-12 years.
Did the EoI translate to tender and order ? Kaveri core is yet to fly after all the modifications.

UCAV program is fully dependent on the availability of engine. Just like once LCA was.
 
It is having fluidic thrust vectoring system with elliptical nozzle.
The models of the Ghatak so far have shown a 2D nozzle. Are they going for an elliptical nozzle now ? At least I hope it is a chevron type, otherwise stealth in rear quarters would be compromised.
Did the EoI translate to tender and order ?
Nope the preparation for a a production run takes some time. GTRE has never mass produced any engine yet. The EoI was sent out to gauge interest among industry & see how much private invest can come into the project.
Kaveri core is yet to fly after all the modifications.
What modification ? The fan ? They deliberately kept the pressure ratio to 3.4:1 instead of 4:1 even though the new fan could give us that. The mass flow rate was also kept the same to maintain as much commonality with the afterburning Kaveri as possible. The afterburner section has been removed that does effect the engine cycle as much. The AB section typically sits behind the turbines & has little to do with the engine cycle. The core of the dry Kaveri is pretty much the same as the one that was flight tested.

But yes it must be flight tested. Either DRDO modifies a civilian plane or get it tested abroad.
UCAV program is fully dependent on the availability of engine. Just like once LCA was.
All aviation projects are dependent on the availability of engines. What's new here ?
 
The models of the Ghatak so far have shown a 2D nozzle. Are they going for an elliptical nozzle now ? At least I hope it is a chevron type, otherwise stealth in rear quarters would be compromised.

Nope the preparation for a a production run takes some time. GTRE has never mass produced any engine yet. The EoI was sent out to gauge interest among industry & see how much private invest can come into the project.

What modification ? The fan ? They deliberately kept the pressure ratio to 3.4:1 instead of 4:1 even though the new fan could give us that. The mass flow rate was also kept the same to maintain as much commonality with the afterburning Kaveri as possible. The afterburner section has been removed that does effect the engine cycle as much. The AB section typically sits behind the turbines & has little to do with the engine cycle. The core of the dry Kaveri is pretty much the same as the one that was flight tested.

But yes it must be flight tested. Either DRDO modifies a civilian plane or get it tested abroad.

All aviation projects are dependent on the availability of engines. What's new here ?
The question is how did the EoI change anything?
That's not true.
How is this not true.