ISRO General News and Updates

[Aaj ka hero]

Mission Accomplished!!

This is the rocket that is going to carry an Indian into space three years from now! And the Chandrayaan 2 also!!

For those who missed it.....


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NOT AN INDIAN but three indians sirji.

 

[Aaj ka hero]

Can somebody explain why they don't add two more solid boosters?

 

[Mikesingh]

S

NOT AN INDIAN but three indians sirji.

Some from ISRO say two astronauts, some say three! I think it's gonna be two due to weight constraints especially after integrating the emergency escape module.

 

[Mikesingh]

Because he blocked the cryogenic technology transfer from Russia to India. That forced us to develop it from scratch causing delay.

But that was a blessing in disguise! Now we don't have to depend on anyone for the high tech cryogenic technology.

 

[Mikesingh]

Cryogenic again performed great,cryogenic engine does provide more thrust for every kg of propellant than other engines giving payload advantage ,many so called "defence " analyst refute that india will ever use cryogenic engines for missiles because arranging such propellants like liquid hydrogen and liquid oxygen in short notice is not feasible but you never know !

The issue is that cryogenic engines cannot work in normal temperature environments. The cryogenic fuel can function well only in temperatures below −183 °C to −253 °C, converting them to liquid form. Hence, all cryogenic rocket engines are either liquid-propellant rocket engines or hybrid rocket engines.

Thus cryogenic engines are initiated only in space as temperatures there are within the range mentioned above.

 

[kurup]

The issue is that cryogenic engines cannot work in normal temperature environments. The cryogenic fuel can function well only in temperatures below −183 °C to −253 °C, converting them to liquid form. Hence, all cryogenic rocket engines are either liquid-propellant rocket engines or hybrid rocket engines.

Thus cryogenic engines are initiated only in space as temperatures there are within the range mentioned above.

First Stage of French Ariane 5 rocket is powered by a Cryo Engine and is lit on ground itself .

 

[Mikesingh]

First Stage of French Ariane 5 rocket is powered by a Cryo Engine and is lit on ground itself .

Ariane 6 has a ‘PHH’ configuration, indicating the sequence of stages:

1. A first stage using strap-on boosters based on solid propulsion (P)

2. A second and third stage using cryogenic liquid oxygen and hydrogen propulsion (H).

Similarly, the Ariane 5 lifts off with the help of strap-on boosters based on solid propulsion (P). The main cryogenic stage (H), ignites later.

Ariane 5

Solid booster stage
Provides the main thrust during takeoff before separating from the main cryogenic stage.

Main cryogenic stage
Central body that ensures propulsion after the solid booster stage separates.

 

[AnantS]

Ariane 6 has a ‘PHH’ configuration, indicating the sequence of stages:

1. A first stage using strap-on boosters based on solid propulsion (P)

2. A second and third stage using cryogenic liquid oxygen and hydrogen propulsion (H).

Similarly, the Ariane 5 lifts off with the help of strap-on boosters based on solid propulsion (P). The main cryogenic stage (H), ignites later.

Ariane 5


Solid booster stage
Provides the main thrust during takeoff before separating from the main cryogenic stage.

Main cryogenic stage
Central body that ensures propulsion after the solid booster stage separates.

I think what @kurup wanted to point out was JAXA's HII series of rockets. They use solid boosters as well, but all stages including first stage are cryo- LH2+LOX, https://en.wikipedia.org/wiki/H-IIA

 

[Mikesingh]

I think what @kurup wanted to point out was JAXA's HII series of rockets. They use solid boosters as well, but all stages including first stage are cryo- LH2+LOX, https://en.wikipedia.org/wiki/H-IIA

The first stage has cryo LH2+LOX but ignites AFTER the boosters with a burn time between 60 and 120 secs depending on the variant.

However, we need a rocket expert/scientist here to clarify whether a cryo engine can be used for lift off.

 

[AnantS]

The first stage has cryo LH2+LOX but ignites AFTER the boosters with a burn time between 60 and 120 secs depending on the variant.

However, we need a rocket expert/scientist here to clarify whether a cryo engine can be used for lift off.

My Guess is thats more to with aim of synchronizing Booster and First stage cutoff and separation. But are you sure first stage ignites after launch? Thats effectively makes it second stage not first stage I think. @IndexTechStyle any comments?

 

[kurup]

Ariane 6 has a ‘PHH’ configuration, indicating the sequence of stages:

1. A first stage using strap-on boosters based on solid propulsion (P)

2. A second and third stage using cryogenic liquid oxygen and hydrogen propulsion (H).

Similarly, the Ariane 5 lifts off with the help of strap-on boosters based on solid propulsion (P). The main cryogenic stage (H), ignites later.

Ariane 5

Solid booster stage
Provides the main thrust during takeoff before separating from the main cryogenic stage.

Main cryogenic stage
Central body that ensures propulsion after the solid booster stage separates.

In case of Ariane 5 the cryo engine Vulcan is ignited 7 sec before the Solid boosters .

http://spaceflight101.com/ariane-5-countdown-timeline/

http://spaceflight101.com/ariane-5-va226/ariane-5-va226-launch-profile/

 

[kurup]

The first stage has cryo LH2+LOX but ignites AFTER the boosters with a burn time between 60 and 120 secs depending on the variant.

However, we need a rocket expert/scientist here to clarify whether a cryo engine can be used for lift off.

Whether a cryo stage alone can lift the rocket will depend on the thrust of the engines .

My point was w.r.t your quote " The issue is that cryogenic engines cannot work in normal temperature environments " .

 

[kurup]

@AnantS , @Mikesingh

The most powerfull active operational rocket in the world today , powered entirely by cryo engines .

https://en.wikipedia.org/wiki/Delta_IV_Heavy

 

[Chinmoy]

Cryogenic again performed great,cryogenic engine does provide more thrust for every kg of propellant than other engines giving payload advantage ,many so called "defence " analyst refute that india will ever use cryogenic engines for missiles because arranging such propellants like liquid hydrogen and liquid oxygen in short notice is not feasible but you never know !

A cryogenic engine for missile system would be impractical at its best.

 

[Chinmoy]

ISRO lines up 10 missions before January 2019

Addressing reporters after the successful launch of the second developmental flight GSLV-MkIII-D2 carrying communication satellite GSAT-29, he said, "we have to achieve 10 missions before January." "That is six satellite missions as well as four launch vehicle missions. Definitely, the task in front of us is very huge," he said.

https://www.moneycontrol.com/news/india/isro-lines-up-10-missions-before-january-2019-3175731.html

 

[Chinmoy]

Someone post this in PeeDeeFff......

Apart from the Ku band communication payload, he said, the satellite also has optical communication payload as well as high resolution camera.

While the Geo High Resolution camera will carry out high resolution imaging,

 

[Indx TechStyle]

I think what @kurup wanted to point out was JAXA's HII series of rockets. They use solid boosters as well, but all stages including first stage are cryo- LH2+LOX, https://en.wikipedia.org/wiki/H-IIA

The first stage has cryo LH2+LOX but ignites AFTER the boosters with a burn time between 60 and 120 secs depending on the variant.

However, we need a rocket expert/scientist here to clarify whether a cryo engine can be used for lift off.

Someone post this in PeeDeeFff......

It's been less crowded, trashier & somewhat funnier these days.

 

[happylion]

Absolutely wrong. Please Google Space Shuttle SSME. That was very much ground lit !!
Firing a Cryo or semicryo engine is not dependent on ambient temperature.

 

[indiatester]

It's been less crowded, trashier & somewhat funnier these days.

I have stopped going there. It was a revelation to me as to how an entire country can be so bigoted and harbor such cruel intentions against us as a nation and culture.
Indian Space Capabilities was one of the few threads that we could visit. I don't know how its doing now.

 

[Indx TechStyle]

I have stopped going there. It was a revelation to me as to how an entire country can be so bigoted and harbor such cruel intentions against us as a nation and culture.
Indian Space Capabilities was one of the few threads that we could visit. I don't know how its doing now.

It sometimes get mild due to depression of Pakistan, right now it has become more disgusted than ever.
Geopolitically, militarily & economicall, they seem to be accepting defeat and don't bother Indians in these things much. But there's a surge in racial attacks and Indian crime news threads. Moderation team is running in action. A Pakistani can call you monkey, rapist, negro or whatever he wants, you'll be banned even if you use word stupid or idiot.

Only thing new to notice is their arguments have started with Chinese. Chinese are buddhists and atheists, pakistanis are muslims, chinese have started criticisng islam in open & here we go.

I'll post it some on relevant thread here.