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35 votes
Accepted

Why does the Indian PSLV rocket have tiny boosters?

Why would these be used instead of just using a larger first stage? Strapping on differently-sized boosters allows variance in payload mass without redesign of the first stage. The PSLV has flown with ...
Organic Marble's user avatar
15 votes
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Why does PSLV use four stages to get to LEO, and why do they alternate solid, liquid, solid, liquid?

PSLV is a bit of a weird duck because it's a transitional step from small solid-rocket designs to larger ones that rely more heavily on liquid rocket engines with higher specific impulse. It doesn't ...
Russell Borogove's user avatar
13 votes
Accepted

What are the advantages of air lit solid boosters in PSLV XL?

This probably has to do with optimizing the launch efficiency of the rocket. More specifically, a rocket has two goals: Get out of the atmosphere Reach orbital velocity The second step can't really ...
Dragongeek's user avatar
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10 votes
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What are the falling parts in this ISRO rocket launch?

According to this article, those are insulation panels, and they're simply lightweight enough to not damage the rocket at the relatively low speeds it's moving in the initial seconds of flight. The ...
Russell Borogove's user avatar
9 votes
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Where do the separated stages of ISRO Launch Vehicle Mark 3 (LVM3) end up?

Here is the map I prepared from NOTAM issued to define drop zones for spent stages of GSLV Mk. III (now known as LVM3) D1 mission that launched GSAT-19 satellite into GTO orbit. https://www.google....
Ohsin's user avatar
  • 1,812
9 votes

Why does the Indian PSLV rocket have tiny boosters?

The answer already posted is excellent. All I want to add is a follow-up question you might want to ask, and my answer to it. Q: OK, so those in particular aren't boosters. But would it ever make ...
Ryan C's user avatar
  • 7,972
9 votes
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How was it difficult for the PSLV to launch a record of 104 satellites?

The key phrase is "satellites separated from the final stage safely without colliding into each other" Let's break that into two pieces: Satellites Separated From Each other- In order to do this, it ...
PearsonArtPhoto's user avatar
  • 121k
8 votes
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What does CLG INIT mean?

"CLG INIT" stands for "closed loop guidance initiation", and means that the launcher is switching into a mode where it actively steers based on its current trajectory rather than a fixed, ...
Russell Borogove's user avatar
6 votes
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help understanding this complicated structure that will deploy HySIS

The blue boxes on upper deck are cubesat deployers by ISIS. One that can house four 3U cubesats is called 'Quadpack' https://www.isispace.nl/products/cubesat-microsatellite-deployers/ ISRO/Antrix also ...
Ohsin's user avatar
  • 1,812
5 votes
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Why is ISRO's PSLV named "Polar"? Are there challenges for other inclinations?

From the beginning of the Wikipedia article that you linked in your question (bolds mine): The Polar Satellite Launch Vehicle, commonly known by its abbreviation PSLV, is an expendable launch system ...
Russell Borogove's user avatar
4 votes

Why is there a "coasting" phase in some space launches?

One reason to stay attached and coast is to let the lower stage finish it's burnout. One of the early SpaceX launch tests failed because they separated too soon. There was still residual fuel exiting ...
Johnny Robinson's user avatar
4 votes
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What benefit do the aerodynamic stabilization "pods" on the PSLV-CA provide?

I would have expected some kind of fin... How do these two cylindrical "pods", symmetrically placed on either side of a cylindrical vehicle, contribute to its aerodynamic stability? Any ...
Russell Borogove's user avatar
2 votes
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What is the purpose of the pairs of cylinders on the interstage of PSLV?

This highly annotated photo says they are separation motors aka "retrorockets". Also Ullage & Retro Rockets, attached to the outer surface of the PSLV, are another interesting mechanism ...
Organic Marble's user avatar
1 vote

How close will the cubesats be when numerous of them are launched simultaneously?

This excellent answer lists a number of different cubesat deploy mechanisms used on PSLV-C43. One could try to check each of their deploy velocities, my guess is that they will be in the ballpark of 0....
uhoh's user avatar
  • 149k
1 vote

How close will the cubesats be when numerous of them are launched simultaneously?

At the moment of release from the dispenser on the launch vehicle or other carrier spacecraft the CubeSats will be very close. After that they will start to naturally separate due to a variety of ...
Carlos N's user avatar
  • 4,474
1 vote

Acceleration Profile of PSLV and GSLV

Created a python code to generate the acceleration, dynamic pressure profiles for the launch vehicles PSLV and GSLV Mk-3. Plots, source and explanation are in my git location https://github.com/...
ravi_ram's user avatar

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