Indian Space Program: News & Discussion - Sept 2016

JayS · Post by **JayS** » 14 Nov 2018 10:06

disha wrote:
JayS wrote:Could that be due to some other planned launch from the same launch pad..?
Tracking and communication. Particularly tracking and communication required by partner space agencies and tracking & comm stations. Each launch sequence needs a commitment on time and resource allocation from partner agencies/tracking stations. This is pure logistics.

That seems like a valid reason. Do you know if this is indeed the reason for Chandrayaan 2....?

Prem · Post by **Prem** » 14 Nov 2018 11:04

https://twitter.com/isro/status/1062575000278822917
The filling of fuel (UH25) and oxidiser (N2O4) in L110 stage has been completed for today's 17:08 (IST) launch of #GSLVMkIIID2 carrying #GSAT29 from SDSC SHAR Sriharikota. Watch this space for all updates.

abhik · Post by **abhik** » 14 Nov 2018 11:12

What is the shelf life of the solid rocket motor once it has been assembled (all the segments are attached) - is there a time limit by when you have to use it?

Prem · Post by **Prem** » 14 Nov 2018 11:25

https://www.isro.gov.in/gslv-mk-iii-d2- ... 45-hrs-ist

JayS · Post by **JayS** » 14 Nov 2018 11:30

I dont know about ISRO launch vehicle specific info but generically speaking solid rockets have very long shelf life, hence they are preferred for Missile application which need shelf life running into a decade or two. The liquid rockets have much smaller shelf life and they have to be fueled just before the launch. The life may vary for liquid fuels ranging from hypergolic fuels to semi cryo to full cryo.

SaiK · Post by **SaiK** » 14 Nov 2018 11:52

http://www.dtic.mil/dtic/tr/fulltext/u2/763879.pdf

lot of variables

https://www.sciencedirect.com/science/a ... 6118302619

Table 6. Correlation between normal and accelerated aging time.

Temperature (°C) Aging condition Time unit Aging time
25 Normal year 2 5 8 10 13 15 20 25
65 Accelerated day 20 45 75 95 120 140 190 235
week 2.8 6.4 10.7 13.5 17.1 20 27.1 33.5

SSridhar · Post by **SSridhar** » 14 Nov 2018 15:37

AFAIK, the segments are cast a few months before.

SSridhar · Post by **SSridhar** » 14 Nov 2018 16:57

Clear skies over SHAR

prasannasimha · Post by **prasannasimha** » 14 Nov 2018 16:59

Mission board gives a GO

JayS · Post by **JayS** » 14 Nov 2018 17:05

Auto launch sequence has started.

D2 stands for second developmental flight. After successful launch of this mission GSLV MK3 will be declared as "Operational".

Since the Sat is going to focus on provide high bandwidth connectivity to J&K and NE, it could be a key capability for Defense perspective as well. Is this something that is planned..? That is whether the bandwidth would be used by our AFs as well in some sense..?

sudhan · Post by **sudhan** » 14 Nov 2018 17:12

- 5 mins to launch..

SSridhar · Post by **SSridhar** » 14 Nov 2018 17:16

Lift off

JayS · Post by **JayS** » 14 Nov 2018 17:16

naarmal lift off wonly

SSridhar · Post by **SSridhar** » 14 Nov 2018 17:17

Performance of solid boosters normal.

sudhan · Post by **sudhan** » 14 Nov 2018 17:17

A female voice reading out the countdown..

Lift off naarmal

SSridhar · Post by **SSridhar** » 14 Nov 2018 17:18

L110 ignition. Normal performance.

JTull · Post by **JTull** » 14 Nov 2018 17:18

112s: L110 ignited. Normal

SSridhar · Post by **SSridhar** » 14 Nov 2018 17:18

Solid Boosters separate.

JTull · Post by **JTull** » 14 Nov 2018 17:19

139.8s: S200s separated

SSridhar · Post by **SSridhar** » 14 Nov 2018 17:20

HSS separation

JayS · Post by **JayS** » 14 Nov 2018 17:20

Performance looks slightly better than expected.

JTull · Post by **JTull** » 14 Nov 2018 17:20

230.8s: Heat Shield separated

sudhan · Post by **sudhan** » 14 Nov 2018 17:20

The ISRO top brass look chill.. Confidence levels must be very high

SSridhar · Post by **SSridhar** » 14 Nov 2018 17:20

All events can be seen on screen.

SSridhar · Post by **SSridhar** » 14 Nov 2018 17:21

C25 stage ign command given. L110 separtaes. C25 ignites

JTull · Post by **JTull** » 14 Nov 2018 17:22

324.8s: C25 ignition confirmed

SSridhar · Post by **SSridhar** » 14 Nov 2018 17:22

C25 performance normal

sudhan · Post by **sudhan** » 14 Nov 2018 17:22

The web streaming sucks.. as per frickin usual

JTull · Post by **JTull** » 14 Nov 2018 17:23

sudhan wrote:The web streaming sucks.. as per frickin usual

HD quality here.

sudhan · Post by **sudhan** » 14 Nov 2018 17:25

Thanks! Looks much better. Time for a susu break while the C25 does its thing

JayS · Post by **JayS** » 14 Nov 2018 17:25

JayS wrote:Performance looks slightly better than expected.

Once the closed loop guidance kicked in at around 150s the gaps was brought down. Till then slightly better performance than predicted. In next launch we will see the gap gone as the predicted trajectory will be fined tuned.

SSridhar · Post by **SSridhar** » 14 Nov 2018 17:30

Everything totally normal.

SSridhar · Post by **SSridhar** » 14 Nov 2018 17:32

Reached

SSridhar · Post by **SSridhar** » 14 Nov 2018 17:33

Looks like a very precise orbit injection.

JTull · Post by **JTull** » 14 Nov 2018 17:33

C25 shutoff
GSAT separated

Vips · Post by **Vips** » 14 Nov 2018 17:33

Mission Accomplished. Congrats ISRO.

sudhan · Post by **sudhan** » 14 Nov 2018 17:33

Handshakes all around. Time to dump GSLV MK3 to the PSLV pile

JayS · Post by **JayS** » 14 Nov 2018 17:34

I just love the Shuddh Hindi commentary. In fact when he uses some Urdu or English word it almost makes me annoyed about it.

The other day I was watching a video on how NASA manages to show uber class videos of launches. They developed high class cameras, some of which are put of Anti-aircraft gun mounts and RADAR controlled with very high focal length lenses (like 4500mm) and which are constantly upgrades. I doubt ISRO has anything remotely close to it. The main aim for NASA's efforts on camera development is to gather engineering data. Awesome footage for jingos is a by-product.

And we have successful insertion. So now GSLV is soon to be officially "Operational".

symontk · Post by **symontk** » 14 Nov 2018 17:36

another vehicle operationalized, congrats

sudhan · Post by **sudhan** » 14 Nov 2018 17:37

Dr. Sivan declares the "Fat boy" GSLV Mk3 operational..