LVM3/GSLV Mark III News, Discussions, Updates and Reports

[Vamsi]

When we will take big jump ?

LVM3-SC will come only after 2025

 

[Swesh]

CE20 engine hot test video

 

[Swesh]

 

[Indx TechStyle]

Successful CE20 uprated Engine Hot Test with 21.8 T vacuum thrust
Nov 09, 2022

The CE20 cryogenic engine indigenously developed for LVM3 has been subjected to successful hot test at an uprated thrust level of 21.8 tonne for the first time on 9th Nov, 2022. This will enhance the LVM3 payload capability upto 450 kg with additional propellant loading.

The major modifications carried out on this test article compared to previous engines was introduction of Thrust Control Valve (TCV) for thrust control. In addition to this 3D printed LOX and LH2 turbine exhaust casings were inducted in the engine for the first time. During this test the engine operated with ~20t thrust level for first 40s, then thrust level was increased to 21.8t by moving thrust control valve. During the test, engine and facility performance was normal and required parameters were achieved.

Thrust Chamber Pressure Curve

Engine Hot Test

 

[Vamsi]

With this we will reach true Medium Lift Capability & with SC120 we will touch 6T to GTO capability

 

[Indx TechStyle]

They should have done it, because LVM3-M2 was actually meant for CY-3 and M2 was ready even before the Oneweb deal was signed.

That has no use in it since OneWeb mission was a SSO one.

An LVM3 being launched today had been given for production 6 months ago. So obviously they didn't make any changes in drawings either.

 

[Vamsi]

That has no use in it since OneWeb mission was a SSO one.

An LVM3 being launched today had been given for production 6 months ago. So obviously they didn't make any changes in drawings either.

M2 rocket was ready in early 2021 itself as per AR-2020-21...and the Oneweb deal was signed early this year.....so M2 would obviously had the necessary modifications to carry 4.3T to GTO....if not M2, upcoming LVM3 assigned for CY-3 i.e M4 would definitely have those modifications

 

[Indx TechStyle]

M2 would obviously had the necessary modifications to carry 4.3T to GTO

4.3 tonnes to GTO is the actual capacity of LVM3 from start per VSSC rating (may be rated down for factor of safety).
Anyway, you can't carry out structural changes in a rocket just by "modifications", you will need to replace a large portion of it.

if not M2, upcoming LVM3 assigned for CY-3 i.e M4 would definitely have those modifications

Are they needed? I don't think so. Chandrayaan-3 fits well in existing capacity.

 

[Vamsi]

4.3 tonnes to GTO is the actual capacity of LVM3 from start per VSSC rating (may be rated down for factor of safety).
Anyway, you can't carry out structural changes in a rocket just by "modifications", you will need to replace a large portion of it.

Are they needed? I don't think so. Chandrayaan-3 fits well in existing capacity.

Yes it's needed....let me explain why....

As Apogee of the orbit increases payload decreases...
For eg:
LEO: 170 × 400km, 8tons (Gaganyaan):
PO: 170 × 45000Km, 3.85 tons (CY-2)
PO: 170 × 186000Km,less than 3t (CY-3)
GTO: 170 × 36000Km, 4.3 tons
As seen above as Apogee increases payload decreases.....so carrying CY-3 into a orbit with Apogee of 186000km will translate to carrying 4.3tons to GTO & 8+ tons to LEO

Without reducing dry mass of C-25, it cannot place CY-3 into 186000Km Apogee Orbit.

 

[Indx TechStyle]

From where did you pick that EPO of Cdy-3 would be 1.86 lakh kilometers?

It looks like it will take a new upper stage engine for India to gain direct TLI and TMI capabilities.
There was no new space tug project either since cancellation of PAM-G at last stages either.

Yes it's needed....let me explain why....

As Apogee of the orbit increases payload decreases...
For eg:
LEO: 170 × 400km, 8tons (Gaganyaan):
PO: 170 × 45000Km, 3.85 tons (CY-2)
PO: 170 × 186000Km,less than 3t (CY-3)
GTO: 170 × 36000Km, 4.3 tons
As seen above as Apogee increases payload decreases.....so carrying CY-3 into a orbit with Apogee of 186000km will translate to carrying 4.3tons to GTO & 8+ tons to LEO

Without reducing dry mass of C-25, it cannot place CY-3 into 186000Km Apogee Orbit.

 

[Vamsi]

From where did you pick that EPO of Cdy-3 would be 1.86 lakh kilometers?

Dr. Somnath's presentation

 

[TopWatcher]

Dr. Somnath's presentation

I read somewhere now rocket will take cy3 payload directly to moon orbit.

 

[Indx TechStyle]

I read somewhere now rocket will take cy3 payload directly to moon orbit.

No, I don't think we have a powerful upper stage for direct TLI injection. Only US, Russia and China can do that at present.

We will have to use continuous orbital maneuvers and off course wait for months for success of every mission.

 

[DumbPilot]

No, I don't think we have a powerful upper stage for direct TLI injection. Only US, Russia and China can do that at present.

We will have to use continuous orbital maneuvers and off course wait for months for success of every mission.

It's not very fancy, but the Oberth effect is very "engineer"-ish in nature

 

[Indx TechStyle]

It's not very fancy, but the Oberth effect is very "engineer"-ish in nature

ISRO tried to engineer and master this project (called PAM-G) on GSLV, back in 2013 and even built a powerful upper stage for direct MEO/GTO injections.

But then, they went back on fixing GSLV and this upper stage never flew. There has been no news on any such project in ISRO since 2016.

 

[TopWatcher]

ISRO tried to engineer and master this project (called PAM-G) on GSLV, back in 2013 and even built a powerful upper stage for direct MEO/GTO injections.

But then, they went back on fixing GSLV and this upper stage never flew. There has been no news on any such project in ISRO since 2016.

There will be a propulsion module, which will take lander/rover to moon orbit. It was clearly mentioned this time orbital maneuvers not required .

 

[TopWatcher]

Any info about skyroot launch date/time/streaming ?

 

[Vamsi]

ISRO tried to engineer and master this project (called PAM-G) on GSLV, back in 2013 and even built a powerful upper stage for direct MEO/GTO injections.

But then, they went back on fixing GSLV and this upper stage never flew. There has been no news on any such project in ISRO since 2016.

no need for new upper stage, LVM3-SC can directly put 4 ton class payload in Lunar transfer trajectory

 

[Swesh]

PAM-G stage shown in one of the slide of wsw-2021

 

[Indx TechStyle]

no need for new upper stage, LVM3-SC can directly put 4 ton class payload in Lunar transfer trajectory

4 tonnes...How?