How many Kilonewtons of Force is needed to reach Orbit?

[Banana Cannibalism]

Hi there guys, I've been doing some math for a lander with custom made rover in a capsule to Orbit and proceed to get it in a cool transporational satellite/ship to Duna so I need the amount of Kilonewtons of Thrust per Ton to reach orbit.

This lander w/ rover and pod is 13.839 tons and I've read that it's roughly 9 Kilonewtons per Ton to lift off the ground. May someone be able to tell me how I can calculate how much fuel and engine thrust I might need to be able to lift this sucker off the ground?

[RoofCat]

Readings...?
- 20!
What 20?!
- What readings??

TWR - Thrust to weight ratio. Weight = Mass x Gravity
For each body different.
Burn time? You obviously need to reach orbital velocity with your chosen acceleration.

[Proteus]

You rather want to know what delta V is needed to get to orbit ... Kilonewtons (used to display Thrust) is only needed to know whether your rocket will be able to lift off or not (and, as roof cat alrady mentioned, is rather displayed as TWR (which should be > 1 if you want to lift off ;) ))

And, having clarified this:
The dV to reach LKO currently seems to be around 3400 m/s
(Currently, because there have been changes between different versions, which also affected the dVs ... so don't expect this to be necessary true for older versions as well)

Source:
https://wiki.kerbalspaceprogram.com/wiki/Kerbin

I for my part always found alexmoons launch window planner to be helpful with my dV calculations:
https://alexmoon.github.io/ksp/
as it also takes the relative positions of the planets into account (starting an interplanetary voyage at different time can make a huge difference with regards to dV requirements)

[Chibbity]

Originally posted by Proteus:

I for my part always found alexmoons launch window planner to be helpful with my dV calculations:
https://alexmoon.github.io/ksp/
as it also takes the relative positions of the planets into account (starting an interplanetary voyage at different time can make a huge difference with regards to dV requirements)

You should check out the in game TWP, it's made by a Squad Dev. Much more convenient than Alt-Tabbing.

https://forum.kerbalspaceprogram.com/index.php?/topic/84005-14x-transfer-window-planner-v1630-march-18/

Works fine in 1.6.

[kamikazi21358]

I don’t know much about the KNs and stuff, but in delta V, I believe it is over 7000 d/V to reach LKO.

[Chibbity]

Originally posted by kamikazi21358:

I don’t know much about the KNs and stuff, but in delta V, I believe it is over 7000 d/V to reach LKO.

It's 3,400.

[andylaugel]

Force = mass x acceleration
acceleration = Force / mass

Pay attention to your units. In this case, Force (total thrust) in kN, mass in metric tons, & acceleration in meters per second per second. You need enough acceleration to overcome acceleration due to gravity, which varies by world.

[kamikazi21358]

Originally posted by Chibbity:

Originally posted by kamikazi21358:

I don’t know much about the KNs and stuff, but in delta V, I believe it is over 7000 d/V to reach LKO.

It's 3,400.

Wait, you’re right.
Correction: he’s right, it’s 3,400, I remember now.
7000-8000 is LEO I believe.

[Proteus]

Originally posted by Chibbity:

Originally posted by Proteus:

I for my part always found alexmoons launch window planner to be helpful with my dV calculations:
https://alexmoon.github.io/ksp/
as it also takes the relative positions of the planets into account (starting an interplanetary voyage at different time can make a huge difference with regards to dV requirements)

You should check out the in game TWP, it's made by a Squad Dev. Much more convenient than Alt-Tabbing.

https://forum.kerbalspaceprogram.com/index.php?/topic/84005-14x-transfer-window-planner-v1630-march-18/

Works fine in 1.6.

Wow, never knew about this mod ... thanks for linking :)

[Chibbity]

Originally posted by Proteus:

Wow, never knew about this mod ... thanks for linking :)

Yeah, I'm always surprised how many players never heard of it, not a problem!

[RoofCat]

Originally posted by kamikazi21358:

Wait, you’re right.
Correction: he’s right, it’s 3,400, I remember now.
7000-8000 is LEO I believe.

LEO orbital speed is almost 8ooo m/s. So the delta v is rather significantly more.

[kamikazi21358]

Originally posted by RoofCat:

Originally posted by kamikazi21358:

Wait, you’re right.
Correction: he’s right, it’s 3,400, I remember now.
7000-8000 is LEO I believe.

LEO orbital speed is almost 8ooo m/s. So the delta v is rather significantly more.

I used to remember this stuff I can’t get it right now

[RoofCat]

Originally posted by kamikazi21358:

Originally posted by RoofCat:

LEO orbital speed is almost 8ooo m/s. So the delta v is rather significantly more.

I used to remember this stuff I can’t get it right now

all I remember from astronomy in school is 8km/s orbit, 11km/s escape, 16km/s solar system escape. So that's all I know :)

[Toastie Buns]

88km/s? Back in time