A noobish question...Currently GSLV MK3 is rated at 4T to GTO. As per understanding, this launch rating is relative to SHAR spaceport. As we know, launch from the equator is most efficient. 1) Does that mean if MK3 was launched (in the same configuration) from say an American or Russian spaceport, its launch capacity would come below 4T relative to SHAR?
2) If MK3 was launched from a sea based platform from the equator in the middle of Indian Ocean, would that enable ISRO to launch more than 4T payload with the same machine?
HAL delivers biggest ever cryogenic propellant tank to ISROHindustan Aeronautics Limited on Monday said it has delivered the biggest cryogenic propellant tank (C32 LH2) ever fabricated by the company to ISRO, much ahead of the contractual schedule.The C32-LH2 tank is a developmental cryogenic propellant tank of aluminium alloy designed for improving the payload capability of GSLV MK-III launching vehicle, HAL said in a release.
According to HAL, the four metre diametric tank is of eight metre length to load 5,755 Kg propellant in the 89 cubic metre volume.
LPSC is in the advanced stage of human rating of C25 stage and development of heavier C32 cryogenic stage for achieving higher payloads.
ISRO uses Liquid Hydrogen (LH2) as fuel and Liquid Oxygen (LOX) as the oxidizer in their cryogenic stages. Theseare stored in propellant tanks which are arranged in tandem with the intertank structure in the middle. These intertanks can have several construction techniques like truss/framed, monocoque, closely stiffened, etc.Presently ISRO intertank structures are made of truss rods, as shown in Fig. 1. These truss rods are meant to allow radial contraction through spherical joints at both ends since the intertank is at ambient temperature, contrary to the low temperature of cryogenic tanks. However, this configuration introduces large, concentrated loads at the truss interfaces, which in turn results in local buckling. Additionally, in this configuration, components on the dome are left open to the aerodynamic flow and acoustic loads.ISRO is thus working on developing a closely stiffened intertank structure (see Fig. 2) that will allow a uniform distribution of stresses at the joint4. However, this configuration will lead to an increase in mass and thus is a non-economical solution. It was found that the closely stiffened intertank contributed to approximately an extra 100 Kg of mass. Therefore, the concept of a common bulkhead seems a plausible approach to minimise mass and overcome the above-mentioned problems of concentrated stresses.
Hardware development and testing at a small scale can be done though it seems very expensive and complex. LN2 may be used instead of LO2 for safety and operational reasons for these experiments. Several core materials are available to be explored (experimentally) for these applications, which may offer better manufacturing feasibility.The manufacturing feasibility for foam-filled honeycomb is another challenging task, along with determining suitable foam and honeycomb combinations. The design of connecting region (transition of CBH dome to external tank) is yet another design area to be worked on. The probable solution to it may be a decoupled ring interface.ISRO has been using such ring interfaces, but modifications are required in maximizing conduction path and minimizing conduction area when it comes to its usage in CBH cryogenic tanks. The manufacturing feasibility and the NDI techniques for each component need to be explored for full-scale development.
GSLV Mk3 roadmap. Semi-cryogenic state would be inducted in GSLV Mk3 M4 mission.Source:
Very interesting. Isn't GSLV Mk3 equipped with SC120 no longer a new rocket different from GSLV Mk3? I'm surprised that it's not named Mk4, but I'm extremely surprised that the mission number is M instead of D.
GROWTH POTENTIAL OF 6 TONS TO GTO IN FUTUREThe payload capability of GSLV MKIII will be increased upto 6 tons to GTO by induction of a High Propulsive Stage (Semi-Cryogenic stage SC120) in lieu of the present L110 and also by increased propellant loading of Cryogenic stage.
To meet ISRO’s objective of achieving higher payloads of 5 tonnes and above in GTO, a powerful, efficient and eco friendly stage was envisaged and this led to the development of Semi cryogenic engine and stage. LPSC has configured and designed a semi-cryogenic core stage, dimensionally optimized to replace the L110 stage of GSLV Mk III. The stage with 120 tonnes of propellant loading and powered by a single SE2000 engine producing a thrust of 200 tonnes will enable GSLV Mk III to carry more than 5.1 tonnes of payload to GTO. Semi-cryogenic engines operate on purified Kerosene (Isrosene) and Liquid Oxygen as propellants and is a combination of high performance, cost-effectiveness, high density impulse and eco friendliness.The engine and stage development is presently at an advanced stage. Engine and stage systems/subsystems have been realised and further testing, qualification and flight stage delivery are progressing as planned.
Here We Go: #Update #Thread As #GSLVMk3 or #LVM3 prepares for its second commercial launch, @isro efforts on enhancing its weight-lifting capacity is gaining pace. I hear that the qualification tests for semi-cryo (SC120) are expected to be completed in a couple of months. 1/n
#GSLVMk3 is India’s heaviest rocket yet. Here’s some perspective: Between May 26, 1999 and Oct 22, 2022, @isro launched 345 foreign satellites, all on #PSLV, which together weigh 9,326.4kg. On Oct 23, 2022, in its first commercial mission, #LVM3 launched 5,796kg. 2/nOf course, these missions are incomparable given that most of the foreign satellites launched by PSLV were ride-sharing payloads and include tens of small, micro and nano satellites… 3/n…But there’s no doubt that the Mk3 clearly enhances India’s prospects. In fact, Isro chairman S Somanath said last week: “The GSLV-Mk3 is India’s best commercial bet.” 4/nAt present, #GSLVMk3 can carry around 4 tonnes to a GTO and at least 6 tonnes to LEO. Induction of the high propulsive SC120, along with increased propellant loading of the cryogenic upper stage (CUS) can enhance this to 6 tonnes (GTO) and 10 tonnes (LEO). 5/nIsro spokesperson Sudheer Kumar said: “GSLVMk3 prog was envisaged to eventually carry at least 10 tonnes to LEO & 6 tonnes to GTO. We’ll achieve this with an upgrade of CUS with additional propellant loading & induction of semi-cryo stage that will replace L110…” 6/n“...Work on semi-cryo engine is almost nearing completion. Qualification tests are in progress. Stage & engine devp phase is complete, and the test stand is getting ready... Sub-system level tests are going on at facilities in Mahendragiri & LPSC,” he added. 7/n#GSLVMk3 is a three-stage vehicle with two solid strap-on motors (S200), one liquid core stage (L110) and a high-thrust cryogenic upper stage (C25). While the S200 will remain the same, the SC120 will replace L110 and C25 will be upgraded. 8/n“...We are expecting qualification to be completed in a couple of months unless some anomalies are found which may call for repeated tests, which are not unusual during the evolution stage,” Kumar said. 9/nHe added that aside from increasing the payload carrying capability, the new configuration would also make the vehicle safer as it will use non-toxic elements compared to L110. 10/n“It'll use refined kerosene, which is like aviation fuel. This means stage handling will be very safe, there'll be an increased capacity, ground systems handling becomes much simpler, storage leakages & human aspect concerns get reduced while handling the stage,” Kumar said. 11/nThe #GSLVMk3 project was first approved in 2002, with a mandate of achieving the capability to launch a four-tonne class satellite to Geosynchronous orbit (GEO), which Isro achieved through three demonstration missions. 12/nThen, the phase-1 of the GSLV-Mk3 continuation programme was approved in June 2018 to build 10 launch vehicles to meet the programmatic requirements to launch communication satellites up to the year 2023. 13/nA year after this approval, the rocket, in its maiden operational flight successfully launched #Chandrayaan2 on July 22, 2019 and had its first commercial mission on October 23, 2022. It is now scheduled to launch 36 more satellites for UK-based @OneWeb in early 2023. n/n
#UPDATE #Rockets #ThreadLate yesterday, @isro said that the CE20 cryogenic engine indigenously developed for #LVM3 (#GSLVMk3) has been successfully hot-tested “at an uprated thrust level of 21.8 t for the first time”. 1/n
“This will enhance #LVM3 payload capability up to 450kg with additional propellant loading. Major modifications carried out on this test article compared to previous engines was introduction of Thrust Control Valve (TCV) for thrust control,” Isro said. 2/n
Additionally, the space agency said a 3D-printed LOX (liquid oxygen) and LH2 (liquid hydrogen) turbine exhaust casings were inducted in the engine for the first time. 3/n
“During this test, the engine operated with around 20t thrust level for the first 40 seconds, then thrust level was increased to 21.8t by moving the thrust control valve. Engine and facility performance was normal and required parameters were achieved,” Isro added. 4/n
I had reported on Oct 31 that as #LVM3 prepares for its second commercial launch, Isro’s efforts on enhancing its weight-lifting capacity is gaining pace. n/n
Successful CE20 uprated Engine Hot Test with 21.8 T vacuum thrust Home/CE20 uprated Engine Hot TestNov 09, 2022The 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.