Difference between revisions of "Talk:Tutorial: How to Get into Orbit"

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(Step 4 - Gravity Turn 45 degrees East until 70km Apoapsis)
(Rocket Doesnt Work Without Superstructure)
 
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I couldn't find a simple written cheat sheet for newbies on how to get into orbit, so I made this article.
 
  
If anyone else has a simpler stock orbiter (cheapest and preferably fewest parts) please share and modify with any game update. The idea is to keep this guide simple for anyone first downloading the game to find the facts they need to get into their first orbit, leaving room for trial and error, and glorious catastrophes.
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== 1.0 Overhaul ==
  
== Title ==
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I've given this tutorial a serious overhaul today for the new 1.0 aerodynamics. I tried to make it such that a new player can memorize it as a sequence of simple key numbers: 100 m/s, 10 degrees, 300 m/s, 10 km, 30 seconds. Let me know what you think!
  
Not sure what works best:
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The old comments on this talk page weren't relevant anymore, so I went ahead and wiped it to a clean slate.
  
*How to Get into Orbit
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[[User:Wcoenen|Wcoenen]] ([[User talk:Wcoenen|talk]]) 21:14, 29 May 2015 (UTC)
*How to Get into Your First Orbit
 
*How to Launch into Orbit
 
*From Launch to Orbit
 
  
I need help picking one.
 
:"How to get into orbit" is pretty good IMO. I don't see the need to change it ;) --[[User:Dgelessus|dgelessus]] <sup>([[User talk:Dgelessus|talk]] &middot; [[Special:Contributions/Dgelessus|logs]])</sup> 13:03, 5 June 2013 (CDT)
 
  
== Jet engines? ==
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The tutorial is good, however, it's not quite clear what our apoapsis should be when we are finished with the first stage, and what angle we should burn at to get it from there to 70+.
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--[[User:Phay|Phay]] ([[User talk:Phay|talk]]) 20:59, 7 June 2015 (UTC)
  
Perhaps this is a really dumb question, but due to the fact that you're inside the atmosphere up to 10,000 metric meters, where you then make your gravity turn, couldn't you use a jet engine with a smaller fuel tank and a RAM air intake? You could get yourself some serious horizontal speed while still inside that 10 KM atmosphere area, then thrust it full power to get an apoapsis as high as your prefered stable orbit apoapsis, and finally dump the jet engine and wait until you're at T=-10s before pulling out the big liquid fuel engine and pulling your periapsis to the same height? You'd save all the fuel from the point where you make your gravity turn to the point where you start blasting it out horizontal.
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:Why would the apoapsis at stage separation be important? The important bit is to get it above 70 km with the second stage. For the angle, the tutorial already instructs to keep the level indicator within the prograde marker at all times - I'm not sure how else to explain it. [[User:Wcoenen|Wcoenen]] ([[User talk:Wcoenen|talk]]) 14:15, 24 June 2015 (UTC)
  
Someone give me a slap for thinking this up or just tell me it'll probably work and test it out. I can't play this game in the slightest, hence my going to a tutorial on how to get into orbit, launching two times and still running out of fuel when I get about a fifth of the world in my orbiting arc.
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:: Depending on your craft the apoapsis might be important at stage separation when the next stage has not enough thrust and the previous stage(s) must get it high enough. It could help beginners to estimate if they launched to step or to shallow (although you've given the altitude so they should be able to determine the profile using that). — [[User:XZise|xZise]] <small>&#91;[[User talk:XZise|talk]]&#93;</small> 21:26, 26 June 2015 (UTC)
  
~Cenitopius (Liam George) @ 04/08/2013 21:03 (ENGLISH DATE FORMAT & TIME ZONE)
 
:Although I never ran the numbers myself, I've heard many times that jet engines are more efficient when getting into orbit, so I assume that you are right. Makes sense, because you don't have to carry the heavy oxidizer. However, as this is a tutorial for beginners who just started with KSP, I don't think that it would be very helpful here - after all, new people want a quick and logical way to start playing, and jet engines on rockets are quite unconventional. Also, there's no need to be extremely efficient (yet).
 
:By the way, you can sign your post by typing <tt><nowiki>--~~~~</nowiki></tt> at the end of it. It'll automatically be replaced with a signature and time stamp, which will look similar to this: --[[User:Dgelessus|dgelessus]]&nbsp;<sup>([[User talk:Dgelessus|talk]]&nbsp;&middot;&nbsp;[[Special:Contributions/Dgelessus|contribs]])</sup> 16:40, 4 August 2013 (CDT) You can also customize that in your [[Special:Preferences|preferences]] if you want. --[[User:Dgelessus|dgelessus]]&nbsp;<sup>([[User talk:Dgelessus|talk]]&nbsp;&middot;&nbsp;[[Special:Contributions/Dgelessus|contribs]])</sup> 16:40, 4 August 2013 (CDT)
 
:In general I would also say this is true, but there are some things you have to be aware of: Jet engines need to start up so your launch sequence become more complex. Also they don't provide very much thrust of only 100 kN or 150 kN, while the Aerospike has a maximum thrust of 175 kN, the LV-T45 has 200 kN and the LV-T30 has 215 kN maximum thrust. Also you waste energy if you going to fast (see [[atmosphere]] about terminal velocity) so you can't build up all velocity only with jet engines.
 
:On another note: “metric meters” don't make sense as the meter is always metric. You only need to say “metric tons”, because there are the long tons and short tons (slightly heavier and lighter than the metric one) in the UK and US. But when you are using metre or meter as a unit of length it is always the SI meter. — [[User:XZise|xZise]] <small>&#91;[[User talk:XZise|talk]]&#93;</small> 17:03, 4 August 2013 (CDT)
 
  
== Not Quite the Cheapest :P ==
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I've calculated total delta-v of this design, and end up with 4258m/s, even assuming LV-T30 Isp is 300s, like in vacuum. But to get to LKO we need 4550m/s, assuming ideal steering, how is this supposed to work? [https://docs.google.com/spreadsheets/d/1spRDn3m8UoR-2DhCbtYyUDwCLadY_Yqk9ewfQ00J4RY/edit?usp=sharing Here]'s calculation. --[[User:Dlazerka|Dlazerka]] ([[User talk:Dlazerka|talk]]) 01:57, 21 April 2016 (UTC)
 
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: Hmm, seems that 4550m/s is an outdated number (before atmospheric refactor). This [[Cheat sheet]] says we actually need 3400m/s for LKO, and I was able to reach it on a ship with 4258m/s. I stand corrected. --[[User:Dlazerka|Dlazerka]] ([[User talk:Dlazerka|talk]]) 08:41, 21 April 2016 (UTC)
Turns out if you replace the T-30 and it's fuel with a [[S1_SRB-KD25k]], it'll have a little more fuel, will cost a bit less, and as an added bonus, it'll start bursting into flames midflight. Of course a new player probably doesn't quite have the science for it just yet, so it's probably not worth editing the article. [[User:Meeh|Meeh]] ([[User talk:Meeh|talk]]) 19:39, 1 June 2014 (CDT)
 
:Ah nvm, apparently that was released later than .22 [[User:Meeh|Meeh]] ([[User talk:Meeh|talk]]) 19:40, 1 June 2014 (CDT)
 
::Yep the new large SRB was released in 0.23.5 and is thus quite recent. Also is cheap currently relative. Let's wait for 0.24 with a proper monetary system so we can determine what is cheap and what not. By the way the T-30 LFE is throttable which might be advantageous. — [[User:XZise|xZise]] <small>&#91;[[User talk:XZise|talk]]&#93;</small> 11:18, 2 June 2014 (CDT)
 
 
 
== Has anyone actually tried these guidelines recently? ==
 
 
 
I tried following the instructions to the letter, and they don't actually get you to orbit. Not for me anyway. So that's not much use for a basic tutorial. It seems to me that whatever basic rocket design is suggested, it should have enough juice to get into orbit with a bit of a safety margin, because a novice can't be expected to fly it at perfect efficiency. I'd also suggest something compatible with Science mode, which means the T800 fuel tank and 909 engine may not be good choices, because you don't get either until you've already collected a few science points. Getting the absolute cheapest option misses the point at this stage, I think. A novice just wants to get into space.
 
 
 
I'd suggest something like
 
* Command Pod Mk1 with Mk16 Parachute and TR-18A Stack Decoupler
 
* FL-T400 Fuel Tank
 
* FL-T200 Fuel Tank
 
* LV-T30 Liquid Fuel Engine
 
* TR-18A Stack Decoupler
 
* three FL-T400 Fuel Tanks
 
* LV-T30 Liquid Fuel Engine
 
 
 
Can a couple of other people pretend to be novices and see if they can get into space _reasonably reliably_ with the above rocket? If so, they or I can adjust the build advice accordingly.
 
[[User:Simons Mith|Simons Mith]] ([[User talk:Simons Mith|talk]]) 14:15, 1 August 2014 (CDT)
 
 
 
:No need to pretend here; I was failing to get into orbit with the page as is, & first time I tried this rocket, I had plenty of fuel to spare (first proper orbit!)
 
:--[[User:Dwattttt|Dwattttt]] ([[User talk:Dwattttt|talk]]) 05:49, 1 September 2014 (CDT)
 
 
 
::I did, no issues here. I even burned retrograde to lower my apoapsis. Make sure you fly east, not west. Navball seems to say east when you are actually flying east. Heading should be 090 degrees. apoapsis was 83km. 6.75/180 liquid fuel, 8.25/220 oxidizer remaining in orbit. had enough fuel to retro back into orbit. used analog throttle if that matters. no mods 0.25 up to date with steam --[[User:Benargee|Benargee]] ([[User talk:Benargee|talk]]) 21:24, 7 November 2014 (CST)
 
 
 
 
 
== Step 4 - Gravity Turn 45 degrees '''East''' until 70km Apoapsis ==
 
 
 
 
 
Is this actually east?, The navball has N pointing down, tutorial describes turning right, i would believe this is west?
 
I am confused though, as most tutorials say "east", while describing right..
 
:Hmm it's definitely east (if you look in the map view and assume north is "up"). My idea would be that it's looking from the inside and not from the top down onto it. Then it get's mirrored. — [[User:XZise|xZise]] <small>&#91;[[User talk:XZise|talk]]&#93;</small> 15:55, 17 December 2014 (CST)
 

Latest revision as of 09:33, 16 February 2021

1.0 Overhaul

I've given this tutorial a serious overhaul today for the new 1.0 aerodynamics. I tried to make it such that a new player can memorize it as a sequence of simple key numbers: 100 m/s, 10 degrees, 300 m/s, 10 km, 30 seconds. Let me know what you think!

The old comments on this talk page weren't relevant anymore, so I went ahead and wiped it to a clean slate.

Wcoenen (talk) 21:14, 29 May 2015 (UTC)


The tutorial is good, however, it's not quite clear what our apoapsis should be when we are finished with the first stage, and what angle we should burn at to get it from there to 70+. --Phay (talk) 20:59, 7 June 2015 (UTC)

Why would the apoapsis at stage separation be important? The important bit is to get it above 70 km with the second stage. For the angle, the tutorial already instructs to keep the level indicator within the prograde marker at all times - I'm not sure how else to explain it. Wcoenen (talk) 14:15, 24 June 2015 (UTC)
Depending on your craft the apoapsis might be important at stage separation when the next stage has not enough thrust and the previous stage(s) must get it high enough. It could help beginners to estimate if they launched to step or to shallow (although you've given the altitude so they should be able to determine the profile using that). — xZise [talk] 21:26, 26 June 2015 (UTC)


I've calculated total delta-v of this design, and end up with 4258m/s, even assuming LV-T30 Isp is 300s, like in vacuum. But to get to LKO we need 4550m/s, assuming ideal steering, how is this supposed to work? Here's calculation. --Dlazerka (talk) 01:57, 21 April 2016 (UTC)

Hmm, seems that 4550m/s is an outdated number (before atmospheric refactor). This Cheat sheet says we actually need 3400m/s for LKO, and I was able to reach it on a ship with 4258m/s. I stand corrected. --Dlazerka (talk) 08:41, 21 April 2016 (UTC)