Indian Human Spaceflight Program (HSP)

[Vamsi]

 

[HariPrasad-1]

Human-rating I think is more about stabilisation, reliability and velocity reduction as safety is paramount here.
So, I don't know whether they have increased any power besides this.

Velocity reduction will result into payload panelty. It can't be the case.

 

[Vamsi]

Velocity reduction will result into payload panelty. It can't be the case.

not velocity reduction,but acceleration

 

[HariPrasad-1]

not velocity reduction,but acceleration

If acceleration is low, velocity will also be low.

 

[Vamsi]

If acceleration is low, velocity will also be low.

No,it won't be. The acceleration by Ion thrusters is very very low when compared to Chemical thrusters, but the final delta-V is much higher when compared to Chemical ones

 

[HariPrasad-1]

No,it won't be. The acceleration by Ion thrusters is very very low when compared to Chemical thrusters, but the final delta-V is much higher when compared to Chemical ones

You messed it up. I simply wrote that gaining higher velocity without faster acceleration is not possible.

 

[Vamsi]

You messed it up. I simply wrote that gaining higher velocity without faster acceleration is not possible.

where did I messed it up?? Also care to explain how gaining higher velocity without faster acceleration is not possible

 

[pipebomb]

not velocity reduction,but acceleration

Nasa has set a max limit of 3g sustained acceleration for its comercial crew program, isro's requirement could be similar. It would be preferable to have a liquid fueled lv for human mission but we work with the tech we have.

Speaking of liquid fueled vehicles, i always wanted to see a clusterd ground lit gslv with 4 or 5( single stearing engine in the middle) vikas engines at core and no second stage. Just a single ce20 upper stage with restart capability. Mungerilal ke haseen sapne.

 

[happylion]

where did I messed it up?? Also care to explain how gaining higher velocity without faster acceleration is not possible

Increasing time to the maximum velocity

 

[HariPrasad-1]

where did I messed it up?? Also care to explain how gaining higher velocity without faster acceleration is not possible

This is a basic physics. Rocket starts from zero velocity. How can it achive faster velocity without faster acceleration? A can needs to reach 0 to 100 in 15 second. Do you any way to achive it with acceleration of 20 meter per second?

 

[Vamsi]

This is a basic physics. Rocket starts from zero velocity. How can it achive faster velocity without faster acceleration? A can needs to reach 0 to 100 in 15 second. Do you any way to achive it with acceleration of 20 meter per second?

then explain how NASA's Dawn spacecraft achieved 11KM/s with just 90mN thrust?? It's acceleration is way too low

 

[Super Flanker]

then explain how NASA's Dawn spacecraft achieved 11KM/s with just 90mN thrust?? It's acceleration is way too low

NASA's Dawn spacecraft was Propelled at a speed of 11.46 KM per second (25,640 mph), not 11 kms/s as told by you.

And by the way, achieving speed of a spacecraft is not possible by only an engine on the craft, it can also be achieved by sling-shoting from the orbit of a planet. When we talk about sling-shoting from a planet's orbit than we come to the concept of "Gravity Assist".

"In orbital mechanics and aerospace engineering, a gravitational slingshot, gravity assist maneuver, or swing-by is the use of the relative movement and gravity of a planet or other astronomical object to alter the path and speed of a spacecraft, typically to save propellant and reduce expense."

So maybe Dawn spacecraft used Gravity Assist to Propel itself to those speeds along with its own engine at the same time.

 

[Vamsi]

NASA's Dawn spacecraft was Propelled at a speed of 11.46 KM per second (25,640 mph), not 11 kms/s as told by you.

And by the way, achieving speed of a spacecraft is not possible by only an engine on the craft, it can also be achieved by sling-shoting from the orbit of a planet. When we talk about sling-shoting from a planet's orbit than we come to the concept of "Gravity Assist".

"In orbital mechanics and aerospace engineering, a gravitational slingshot, gravity assist maneuver, or swing-by is the use of the relative movement and gravity of a planet or other astronomical object to alter the path and speed of a spacecraft, typically to save propellant and reduce expense."

View attachment 157139

So maybe Dawn spacecraft used Gravity Assist to Propel itself to those speeds along with its own engine at the same time.

Dude it clearly achieved a delta V of 11.2KM/s using Electric-propulsiom

 

[Super Flanker]

Dude it clearly achieved a delta V of 11.2KM/s using Electric-propulsiom

This is the official website of NASA, they too are mentioning about Gravity Assist. I don't know what you meant by Delta V. Other than the website which I shared, you will find several other sources on the internet which confirm the usage of Gravity Assist.

NASA - NASA Spacecraft Falling For Mars

 

[Super Flanker]

This is a basic physics. Rocket starts from zero velocity. How can it achive faster velocity without faster acceleration? A can needs to reach 0 to 100 in 15 second. Do you any way to achive it with acceleration of 20 meter per second?

Another way to achieve acceleration of a space craft in space is by the utilisation of Gravity Assist.

(~Basically you use the gravity of a planet to sling-shot your craft to alter the path and speed of a spacecraft, typically to save propellant and reduce expense~)

 

[mokoman]

This is the official website of NASA, they too are mentioning about Gravity Assist. I don't know what you meant by Delta V. Other than the website which I shared, you will find several other sources on the internet which confirm the usage of Gravity Assist.

NASA - NASA Spacecraft Falling For Mars

IMHO @Vamsi is talking about space travel , not liftoff rockets , if u could sustain even 1cm velocity / sec for a day , u will end up reaching 1km/sec .

delta v is change in velocity . since there is no friction in space , once u hit a certain velocity , u will keep that velocity until u want to change it .

its like how on earth u travel by going from point A -> B . in space i guess u can map out travel with accelerating to a certain velocity V , then before reaching destination , decelerate to 0 so on.

 

[Super Flanker]

IMHO @Vamsi is talking about space travel , not liftoff rockets , if u could sustain even 1cm velocity / sec for a day , u will end up reaching 1km/sec .

delta v is change in velocity . since there is no friction in space , once u hit a certain velocity , u will keep that velocity until u want to change it .

its like how on earth u travel by going from point A -> B . in space i guess u can map out travel with accelerating to a certain velocity V , then before reaching destination , decelerate to 0 so on.

In space there is no friction because there is no fluid in space, space is a vacuum, for example in space if you manage to accelerate yourself to 10 kms/sec than that means you will be able to travel 10 continuosly.

But like I said again, NASA Already confirmed that they had used Gravity Assist in the mission at one point, the planet they used for Gravity Assist was Mars.

 

[Indx TechStyle]

Manned Gaganyaan now for 2024.

 

[Vamsi]

Manned Gaganyaan now for 2024.

source??

 

[Super Flanker]

source??

Several sources have made a comment in the last few days saying that : "Chandrayaan-3 launch by 2022-end, Gaganyaan manned mission in 2024"

SOURCES :-

Chandrayaan-3 launch by 2022-end, Gaganyaan manned mission in 2024: Minister Jitendra Singh

India's space programme and launch missions have been delayed by the pandemic, thus affecting the timelines of high-profile missions such as Chandrayaan-3 (the third Lunar mission) and Gaganyaan (human spaceflight mission).

www.wionews.com

Here's why ISRO will conduct two unmanned 'abort mission' to space before Gaganyaan

The unmanned 'Abort Mission' is a part of ISRO's roadmap for the country's first manned flight to space, the Gaganyaan scheduled for 2024.

www.dnaindia.com

For safety of Gaganyaan crew, ISRO will simulate failure with ‘abort missions’

The ISRO chief, S Somanath, pointed out that while the main purpose of the Gaganyaan mission is to demonstrate India’s capability, it is also the first step toward an Indian Space Station in the future.

indianexpress.com