ARM SLS Parts and the Start of The Career mode age?

[Red Iron Crown]

What about one craft, one launch that accomplishes multiple missions? Also the more efficent design can be used at a lower budget level (budget sold for Reputation and tech), opening more missions (for more bugetary opjectives) and different parts.

It's hard to know how this is all going to work. Being able to exchange the currencies around is going to make it very difficult to make career a challenge for veterans who can do a lot with few parts, I think.

[Rakaydos]

It's hard to know how this is all going to work. Being able to exchange the currencies around is going to make it very difficult to make career a challenge for veterans who can do a lot with few parts, I think.

And this is different than completing the Science tree in two missions... how?

That said, you are correct, we can only speculate at this point- I consider that an unstated axiom. but being able to exchange currencies was part of the initial announcment of budgets, so looking at budgets in isolation from Repution and Missions (which at this point are equally fuzzy) isnt looking at the whole picutre, any more than looking at stats without cost is incomplete.

My speculation is focused arounf fitting the earlier "Carear mode is a sandboxy tuturial for the real sandbox" with the more recent "budgets, tech and reputaion will make carear feature-complete." The idea being "How can budgets, tech and reputation guide a new kerbal player into learning to enjoy sandbox?"

[MKI]

It's hard to know how this is all going to work. Being able to exchange the currencies around is going to make it very difficult to make career a challenge for veterans who can do a lot with few parts, I think.

It will be hard, Im sure once most of the career limitations are implimented, veteran players will still be able to do a lot easily in the game. That will almost always stay. I do not see the game getting "harder" in the sense career will be a grind or a complete challenge to those who know how to play already. I do want to see more strategy in how the Career is played. Choosing what tech to unlock is already an example of that.

@xrayfishx

Truthfully I don't think you would get much done beyond minimal bragging rights if you make an SSTO to Tylo with the new parts. I bet the payload would consist of a chair with a kerbal in it?

And who says the tech tree progression isn't already starting to be implimented? What if these new parts are just replacements for the older parts? Who says they have to be the SAME SIZE? Being bigger does mean you shouldn't be making ships out of them, as you have to deal with SAS and lack of large parts to support. (all science parts are fairly small, besides science lab).

Don't assume the parts effeciency is very overwhelming compared to its price. For all we know they could be 10 times more expensive and only useful for when you invest most of your resources into buying them. Since you can do everything without them, its not exactly a good reason to make them cheap or even close to cheap to use.

@rakaydos

I see what you mean by making it effecient to use certain parts for certain tasks. So then everything has its place, this presents an issue with limitations. If everything is balanced for a certain task, there wont be very many places for every engine without adding more balancing factors. It also makes progressing in the Tech tree another mode of "unlock to sandbox", where having all the tech isn't much better than having half or a forth of the tech.

balancing for sandbox makes career more balanced, but also very boring and not very interesting to play. Why play a game where progresion is nothing more than unlocking things that don't give you better capabilites? I know for a fact many people believe making sandbox completely balanced will make a "fun" career but it will be the ultimate doom for this game. Why impliment career if its not a challenge on its own? Already Career is pretty much Sandbox mode with some fun little messages here and there, and some incredibly easy progression.

Something as simple as using old parts until you have the funding and research to support the end game launch system is already better than unlocking the usual parts and a linear progression of launch types all just so you use less parts in making a launcher.

Edited April 8, 2014 by MKI

[MKI]

*Bump*

I see my thread is referenced in locked threads that relate to the very similar topic of NASA pack engine balancing.

I feel this thread is a good read (regardless of how many people i have quoted no more mass quotes )

So it needs an update before its really dead(thats legal right mods?)

[John FX]

I`ve been saying this in every `nerf the new parts` thread I can.

People need to start thinking outside the sandbox.

It's hard to know how this is all going to work. Being able to exchange the currencies around is going to make it very difficult to make career a challenge for veterans who can do a lot with few parts, I think.

Career will never be a challenge for someone who can do a return trip to Duna in six parts. It is folly to try and challenge those people. They are ninjas.

Edited April 12, 2014 by John FX

[Whirligig Girl]

Look at the KS-25 Cluster. 4 engines have 3200 kN of thrust. 1 engine has 800 kN of thrust, which is not even enough to launch a decent Rockomax craft. A SINGLE RS-25 rocket engine (Real world rocket) has 2,279 kN of thrust. That is MUCH more thrust. The KS-25 engine has an Ispv of 360s, and Ispa of 320s. The RS-25 engine has an Ispv of 452s and an Ispa of 366. The KS-25 is not OP.

The KR-2L is OP, and it's just confusing. It's meant to be used as a lifting engine, but I usually use it for upper stages much more often.

Now look at the KR-2L Advanced Engine. It is a heavy lifting engine, probably meant to be a J-2X or F-1 Engine, depending on how you use it. It is too low thrust to be a first stage of a Saturn V, and only 1 fits on a 3.75m stack. It's way too high thrust for an upper stage engine, and while it's atmospheric efficiency is pretty crappy; it's efficiency quickly improves to be one of the most efficient engines. I think that the KR-2L needs a rebalance and a sister to replace the other thing that the KR-2L engine was supposed to do.

The LFB KR-1x2 is not really OP, but you get it the same time as the mainsail so there's no reason to use the mainsail. If it was postponed until later in the tech tree, it would be better balanced.

Edited April 12, 2014 by GregroxMun

[John FX]

Look at the KS-25 Cluster. 4 engines have 3200 kN of thrust. 1 engine has 800 kN of thrust, which is not even enough to launch a decent Rockomax craft. A SINGLE RS-25 rocket engine (Real world rocket) has 2,279 kN of thrust. That is MUCH more thrust. The KS-25 engine has an Ispv of 360s, and Ispa of 320s. The RS-25 engine has an Ispv of 452s and an Ispa of 366. The KS-25 is not OP.

The KR-2L is OP, and it's just confusing. It's meant to be used as a lifting engine, but I usually use it for upper stages much more often.

Now look at the KR-2L Advanced Engine. It is a heavy lifting engine, probably meant to be a J-2X or F-1 Engine, depending on how you use it. It is too low thrust to be a first stage of a Saturn V, and only 1 fits on a 3.75m stack. It's way too high thrust for an upper stage engine, and while it's atmospheric efficiency is pretty crappy; it's efficiency quickly improves to be one of the most efficient engines. I think that the KR-2L needs a rebalance and a sister to replace the other thing that the KR-2L engine was supposed to do.

The LFB KR-1x2 is not really OP, but you get it the same time as the mainsail so there's no reason to use the mainsail. If it was postponed until later in the tech tree, it would be better balanced.

I must say your description there of the KR-2L Advanced Engine makes it sound ideal for moving asteroids...

I think myself the NASA parts were jammed into an existing tech tree and should have their own nodes later than the current tech.

[Whirligig Girl]

I must say your description there of the KR-2L Advanced Engine makes it sound ideal for moving asteroids...

I think myself the NASA parts were jammed into an existing tech tree and should have their own nodes later than the current tech.

1.(Facepalm at my own ineptitude)

2. Yeah, they did make a new node for The Klaw, why not the rocket parts?

[MKI]

1.(Facepalm at my own ineptitude)

2. Yeah, they did make a new node for The Klaw, why not the rocket parts?

I feel maybe the need more parts to make things more "pretty"(in the tech tree shape that is lol) which obviously will come in time. Even if that means the parts come before earlier larger parts can "shine"

OR

The prices will balance things out considerably (especially in the Mainsail issue)

[Jouni]

Look at the KS-25 Cluster. 4 engines have 3200 kN of thrust. 1 engine has 800 kN of thrust, which is not even enough to launch a decent Rockomax craft. A SINGLE RS-25 rocket engine (Real world rocket) has 2,279 kN of thrust. That is MUCH more thrust. The KS-25 engine has an Ispv of 360s, and Ispa of 320s. The RS-25 engine has an Ispv of 452s and an Ispa of 366. The KS-25 is not OP.

In KSP, the Isp of engines using LOX/LH2 has been downscaled a bit. While the best real-world engines reach about 460 seconds, the best KSP engines only go to 390 seconds. Based on this scaling, a more faithful imitation the SLS engine cluster should have 310/380 seconds of Isp.

The thrust, on the other hand, is way too high. The real SLS first stage will not be able to lift itself without boosters. We get dimensions similar to the real first stage by stacking three S3-14400 fuel tanks. Based on this, the engine cluster should have no more than 2400 kN of thrust, or 600 kN per engine.

The KR-2L is OP, and it's just confusing. It's meant to be used as a lifting engine, but I usually use it for upper stages much more often.

Now look at the KR-2L Advanced Engine. It is a heavy lifting engine, probably meant to be a J-2X or F-1 Engine, depending on how you use it. It is too low thrust to be a first stage of a Saturn V, and only 1 fits on a 3.75m stack. It's way too high thrust for an upper stage engine, and while it's atmospheric efficiency is pretty crappy; it's efficiency quickly improves to be one of the most efficient engines. I think that the KR-2L needs a rebalance and a sister to replace the other thing that the KR-2L engine was supposed to do.

It's basically a gigantic J-2X engine. The SLS upper stage will have a cluster of three of them. Based on the TWR figures for the real upper stage, and considering that the KSP version of SLS can handle bigger payloads relative to the size of the rocket, a KR-2L engine replacing the J-2X engine cluster should have about 1200 kN of thrust. Its Isp figures are basically fine.

The LFB KR-1x2 is not really OP, but you get it the same time as the mainsail so there's no reason to use the mainsail. If it was postponed until later in the tech tree, it would be better balanced.

The real booster will have more thrust than SLS first stage, while its Isp is much lower, due to using LOX/RP-1. Considering that the Mainsail is essentially an F-1 engine, the booster could just have the statistics of two Mainsails and one jumbo tank. By adding four more jumbo tanks, we would reach the same TWR as the real booster, while making the stack ridiculously high.

The real dimensions of the booster correspond to a stack with two additional jumbo tanks. This is about as high as the first stage, and its mass should also be almost the same, due to LOX/RP-1 fuel tanks having more mass than LOX/LH2 fuel tanks of similar size.

[MKI]

Don't forget the real SLS is designed for entering LEO, not LKO which is almost half of what it actually takes. So there must be some scaling back in capabilities overall, compared to real life engines.

Real life comparisons and kerbal space program never worked for me, especially engine values. I guess the new parts being based off real engines offer a window of realism in this rather unrealistic game.

[Jouni]

Don't forget the real SLS is designed for entering LEO, not LKO which is almost half of what it actually takes. So there must be some scaling back in capabilities overall, compared to real life engines.

Real life comparisons and kerbal space program never worked for me, especially engine values. I guess the new parts being based off real engines offer a window of realism in this rather unrealistic game.

Real life comparisons are pretty much the only reason I play KSP. If things didn't mostly like in the real world, it would be just a boring sandbox game with imaginary stuff. When the performance of the rockets is based on other things than just gameplay considerations, the game becomes much more interesting.

Things are obviously scaled in a number of ways. Kerbals and their rockets are a lot smaller than us and our rockets. Engines and fuel tanks are heavier than in our rockets. Heavy lifting engines are more efficient in KSP than in the real world, while upper stage engines are less efficient. Scaling like that is not a problem, as long as it's done consistently everywhere.

[John FX]

For a simple example, lets imagine you have 10,000 of whatever the money is called and you have to do a mission. You mission requires 5KDv.

The easiest solution is a mainsail stage and a NERVA stage. Simple. (yes I know but this is a logic example, not a realistic rocket building example, let it slide)

A NERVA costs 9,000 a Mainsail costs 8,000 and a rockomax 47S costs 200. Your fuel and payload costs 3000. You still need power and RCS...

Why don`t you slap a fuelled NERVA on top of a fuelled mainsail and get the best rocket you can?

Because it is balanced by being in a career setting and financial restrictions.

Looks like you`ll have to use rockomaxes to launch your craft this time until you can get a few missions done underbudget.

If you want real world considerations to be applied to your rocket then you need a budget...

To balance sandbox is to unbalance career. At a minimum it removes the fun from career by making everything bland and removing the reason for getting better tech.

The later engines and parts HAVE to be objectively better than the previous ones or there is no need for progression.

By definition this will make them unbalanced in sandbox.

[Red Iron Crown]

To balance sandbox is to unbalance career. At a minimum it removes the fun from career by making everything bland and removing the reason for getting better tech.

The later engines and parts HAVE to be objectively better than the previous ones or there is no need for progression.

I don't believe this is necessarily true. Engines in KSP, for example, have generally balanced TWR and Isp, which works for both sandbox and career. If you want tech tree progression to open new possibilities, have the parts at the extreme ends of the scale unlock later. An LVT-30 is a good starter engine, it is decent at most tasks but not the best at any. As higher TWR parts are unlocked, like Mainsails, the player's lifters become more capable. As higher Isp parts are unlocked, like LV-Ns, more efficient interplanetary missions are possible. The later engines aren't objectively better, just more specialized.

So there would be a spectrum of engines that trade off against each other, balancing in sandbox, while still having more capabilities unlocked as the player progresses through the tech tree. That's without even using the cost values, which can add further career mode balance tuning.

[Random Tank]

Red iron crown makes a good point; why do you want the SLS engines to make others pointless? Pretty much no engine that was in .23 made any other pointless (apart from the LV-1s), so why should the SLS engines do it? All it would do was waste a spot in the editor menu. It's much easier and better to make it that each engine has a specific purpose, like it was in .23 and as stupid_chris's rebalance pack now does...

Now, people say you can balance it with cost; I say this really isn't the way to do it. Why? Because lots of people will work out which engine out of the heavy lifters is the most effective per unit cost; and only use the best one to save money. But if you make it so each engine has a specific use a purpose, how much they cost and which one is the best becomes null.

Here's the problem with money balancing explained...

You make the SLS parts cost more (vs. effectiveness) than the Mainsail and Skipper: Now everyone will just continue to use the Rockomax engines; and when people need to carry heavier loads, they'll just use more Mainsails as they are cheaper than using SLS

You make the SLS parts cost less (vs. effectiveness) than the Mainsail and Skipper: Now everyone will just start using the SLS parts instead of the Rockomax parts, as they do the same job, but cheaper. You could even get to a point where people continue to use the LV-T engines until they have enough science to skip the Mainsail and just go straight for the SLS parts.

But if you changed it so the Mainsail and SLS parts are useful even when you have both, there is no problem anymore; people won't need to work out which is more money efficient, as the engines fill different roles....

Edited May 2, 2014 by Random Tank

[rkman]

Look at the KS-25 Cluster. 4 engines have 3200 kN of thrust.

That is not much more than 2 Mainsails - but 2 mainsails don't neatly fit under a 3.75m tank.

One under-appreciated difference between the SLS engines and older stock engines is that the new engines have a higher thrust-to-size ratio. It's like having LV-T45's with the thrust of a Skipper. Thanks to that we can build big heavy rockets that actually look like rockets.

Until now large rockets in KSP were wide instead of tall simply because a tall slender rocket does not have enough surface area available to mount enough of the older stock engines to get enough thrust (not without a lot of part clipping).

[Jouni]

One under-appreciated difference between the SLS engines and older stock engines is that the new engines have a higher thrust-to-size ratio. It's like having LV-T45's with the thrust of a Skipper. Thanks to that we can build big heavy rockets that actually look like rockets.

Only the LFB has a good thrust-to-size ratio. The 3.75 m engines are weaker than average in this respect.

The thrust-to-size ratios (thrust / diameter^3) of the inline rocket engines, from the best to the worst, are the following:

1. LFB 128.00
   
2. 48-7S 122.88
   
3. LV-T30 110.08
   
4. LV-T45 102.40
   
5. Mainsail 96.00
   
6. Aerospike 89.60
   
7. RAPIER 89.60
   
8. KS-25x4 60.68
   
9. KR-2L 47.41
   
10. Skipper 41.60
    
11. LV-N 30.72
    
12. LV-909 25.60
    
13. LV-1 16.38
    
14. Poodle 14.08
    

Things obviously change, if we look at the thrust-to-area ratios of the engines. While the thrust-to-size ratio tells how tall the rocket can be relative to engine diameter, thrust-to-area ratio is more useful, if we fix the diameter of the rocket in advance, and look for the most powerful engines. The same engines are in the following order, according to their thrust-to-area ratios:

1. LFB 320.00
   
2. Mainsail 240.00
   
3. KS-25x4 227.56
   
4. KR-2L 177.78
   
5. LV-T30 137.60
   
6. LV-T45 128.00
   
7. Aerospike 112.00
   
8. RAPIER 112.00
   
9. Skipper 104.00
   
10. 48-7S 76.80
    
11. LV-N 38.40
    
12. Poodle 35.20
    
13. LV-909 32.00
    
14. LV-1 10.24
    

[Vonar]

Those who are complaining about the SLS/NASA parts being over powered in comparison to stock KSP stuff need to keep in mind that the SLS is designed to be a heavy lift rocket from the beginning and is the first real Heavy Lift rocket that we as a community have gotten access to in KSP. The SLS Block II configuration calls for the ability to deliver 130 Tons to Low Earth Orbit. With the exception of the Falcon Heavy that can lift 53 tons to LEO that's more then five times the launch potential of the next closest rocket that anyone in the world currently uses. Saying the rocket is over powered and makes things like Duna, asteroid, and Jool missions too easy is like complaining about rain in rainy season as with the exception of a mission to Jupiter the SLS is designed from the ground up to accomplish return missions with ease.

What the SLS does need is a better sepratron rocket to clear the bigger boosters away from the core of the rocket when you stage. The current ones fail to make any difference more often then not, and when launching large payloads the side boosters may actually be underpowered in comparison to what NASA will have irl as with a 130 ton test payload I was struggling to clear 4,000 ft before my boosters ran out of fuel and had to be jettisoned. Irl the boosters are expected to last 120 seconds into the flight at which point the rocket would probably be in the 7,000-12,000 ft department.

[Random Tank]

Those who are complaining about the SLS/NASA parts being over powered in comparison to stock KSP stuff need to keep in mind that the SLS is designed to be a heavy lift rocket from the beginning and is the first real Heavy Lift rocket that we as a community have gotten access to in KSP. The SLS Block II configuration calls for the ability to deliver 130 Tons to Low Earth Orbit. With the exception of the Falcon Heavy that can lift 53 tons to LEO that's more then five times the launch potential of the next closest rocket that anyone in the world currently uses. Saying the rocket is over powered and makes things like Duna, asteroid, and Jool missions too easy is like complaining about rain in rainy season as with the exception of a mission to Jupiter the SLS is designed from the ground up to accomplish return missions with ease.

*sigh*

The whole claim of the SLS engines being overpowered wasn't because of their lifting capacity (apart from the KR-2L); it's because they are way too efficient! I don't know why these engines can do what a mainsail does, but use less fuel doing it; they're supposed to do what the Mainsail can't do, not replace it.

Ofc they're supposed to be lifting engines, I agree, and the KS-25x4 has a very good TWR, it's just too efficient; the while trend of every other engine on this game is that as TWR increases, ISP decreases, do why should the SLS engines (and the 48-7S) break this rule. Go look at Stupid_chris's rebalance pack; he actually increases the thrust of the KS-25x4's thrust, but it's weight too, to more define it as a heavy lifter, but he makes it's efficiency worse than the Mainsail, as it should be! It's very easy to make the SLS engines fill a different role to the Mainsail, all you have to do is hit their efficiency so that they can't replace the Rockomax engines....

(The KS-2L needs a thrust drop and weight increase though; it has the highest TWR in the game and it's supposed to be a vacuum engine....:S)

[Dodgey]

Also, what does real life have to do with it? That is my question Vonar.

[John FX]

I don't believe this is necessarily true. Engines in KSP, for example, have generally balanced TWR and Isp, which works for both sandbox and career. If you want tech tree progression to open new possibilities, have the parts at the extreme ends of the scale unlock later. An LVT-30 is a good starter engine, it is decent at most tasks but not the best at any. As higher TWR parts are unlocked, like Mainsails, the player's lifters become more capable. As higher Isp parts are unlocked, like LV-Ns, more efficient interplanetary missions are possible. The later engines aren't objectively better, just more specialized.

So there would be a spectrum of engines that trade off against each other, balancing in sandbox, while still having more capabilities unlocked as the player progresses through the tech tree. That's without even using the cost values, which can add further career mode balance tuning.

DISCLAIMER : all figures in this post are pre-23.5 and taken from here

It`s a calculator that tells you the lowest mass craft for a given payload, TWR and Dv input. I`ve ignored the ION for this examination.

The lowest mass craft (which will most likely give you the best income from a mission due to reduced fuel costs etc) for a normal manned payload (5 ton) and a TWR of 1 uses the 48-7s. There is not a better engine. It is objectively the best engine. From 100Dv to 5000Dv it`s the lightest way to get a desired amount of Dv and a TWR of 1.

You would have to want a much lower TWR or a very small payload to use a different engine. For pretty much every manned craft with a decent TWR it`s the 48-7s.

Try it yourself and try to get it to tell you a different answer than the 48-7s being the best engine for the values you input. You`ll have a craft that is not one you normally fly I`ll bet.

Unless there is a penalty for using a large number of parts then the rockomax 48-7s is objectively the best engine. For payloads over 5t, TWR 1, and Dv over 100.

For low TWR/high Dv craft it`s usually the NERVA. If you go to the extremes of craft (huge/small) then you may find fringe cases where other engines are better.

The `balancing` of sandbox pre-23.5 doesn`t really exist in my mind when two engines make all the others pointless except for heavy lifting...

The new engines in my mind were put there as asteroid movers. High vacuum efficiency, terrible atmo ISP, high thrust, high TWR.

Whether they do that well is another matter I suppose.

[Red Iron Crown]

John FX, the 48-7S is commonly considered overpowered, too. Showing that an overpowered part exists doesn't nullify the concept of sandbox balance, nor is it a good justification to add parts that are even more unbalanced, IMO. If anything, the 48-7S is an illustration of how overpowered parts crowd out the others in efficient designs.

The ions and NERVAs could be considered overpowered, but the balance with those comes from long burn times and lack of larger versions appropriate for big craft. Effectively, player patience and part count considerations help balance those.

As an aside, your link is broken for me, were you meaning to link to tavert's charts?

Edited May 3, 2014 by Red Iron Crown

[rkman]

thrust-to-area ratio..

Mainsail 240.00

KS-25x4 227.56

I get different numbers:

Mainsail (1500kN, surface 4.9) = 306

KS-25x4 (3200kN, surface 11) = 290 (taking the diameter of the entire cluster mounting: 3,75m)

When taking the surface area of the actual engines of the KS-25x4 instead of the diameter of the entire cluster, the thrust-to-area ratio of the KS-25x4 engines is much better, easily topping the Mainsail.

Like i said: 2 mainsails do not fit neatly under a 3.75m tank, but four engines of 800kN each and a diameter of about half that of a mainsail (that's the KS-25x4 cluster) fit nicely. Those engines are significantly smaller and more powerful than a skipper.

I'm not saying it is unbalanced, i'm saying it is the new standard (though the isp and twr might be a bit to much). The effect of it is that we can build big rockets that look like rockets instead of cathedrals.

Also i am not waiting for Squad to produce more engines that follow that standard, for personal use i'm modding engines from various part packs.

[Jouni]

I get different numbers:

Mainsail (1500kN, surface 4.9) = 306

KS-25x4 (3200kN, surface 11) = 290 (taking the diameter of the entire cluster mounting: 3,75m)

Constant factors are unnecessary. I just used the square of the diameter as an estimate for the surface area.

Like i said: 2 mainsails do not fit neatly under a 3.75m tank, but four engines of 800kN each and a diameter of about half that of a mainsail (that's the KS-25x4 cluster) fit nicely. Those engines are significantly smaller and more powerful than a skipper.

Those four engines don't exist, except as graphic elements. The KS-25x4 engine cluster is a single engine, just like the RAPIER.

Anyway, if you want to build a powerful single-stack 3.75 m rocket, your best bet is building an adapter for 2.5 m parts. With tail connectors and Rockomax adapters, you can fit four Mainsails below a 3.75 fuel tank without the engines clipping at all. (You could also use LFBs, but they would clip a bit.) The result is not too different from the KS-25x4 (except for 6000 kN of thrust instead of 3200 kN), as it's not strictly a 3.75 m part either.

[rkman]

With tail connectors and Rockomax adapters, you can fit four Mainsails below a 3.75 fuel tank without the engines clipping at all.

That could lift some 45, maybe 50tons to lko. Once you get to 100 ton payload, using the old stock engines you are forced to build wide rather than tall.

Those four engines don't exist, except as graphic elements. The KS-25x4 engine cluster is a single engine

They exist in my gamedata folder, and combined with procedural tanks large rockets are a lot less finicky to build and look a lot nicer than using old stock parts.

Serial staged rockets up to at least 150 tons to LKO are no problem (thanks in no small part to Squad fixing the attach joints).

The first stage of those is in the range of 5 to 7.5m diameter. That's a lot of surface but not enough to get enough thrust if you use Mainsails, but it is enough if using engines with specs and dimensions like the SLS engines. http://forum.kerbalspaceprogram.com/threads/29533-What-did-you-do-in-KSP-today?p=1128657&viewfull=1#post1128657