A visual criticism of the Shuttle engine

[GoSlash27]

How does the vector engine stack up in sandbox mode? Or is this complaint only relevant in career or science mode?

sardia,

Actually, I think this complaint is *only* relevant in sandbox mode, if then. The Vector doesn't seem to be a very good engine for career or science mode according to my testing thus far.

Best,

-Slashy

[spikeyhat09]

-snip-

Edit: Wait, spikeyhat09, where's your fairing? No wonder that would be a nightmare to orchestrate. And if those are clusters of five or six Vectors on those boosters, no wonder it could finally make it to orbit; you just forced it! A fairing would allow that payload to be lifted much more efficiently and much less forcefully (bringing it up more forcefully and fighting drag uses more fuel and requires more engine mass), which would most-likely allow Mammoths to easily take over the lifting job for that rocket.

i had a fairing initially but it ended up being 2/3 the length of the rocket. it would actually bend inside the fairing and blow itself up. pretty quickly i realized that it had way more than enough muscle to do what i wanted. a pretty stupidly large amount of muscle in fact. plus that guy said aerodynamics dont matter anymore for whatever reason (why did they do that exactly?)

also the thing that makes the shuttle engine better than the mammoth is the incredible gimbal range and the fact that you can make clusters of much more than 4 in the same amount of space.

Edited November 11, 2015 by spikeyhat09

[G'th]

The question is, why?

Do you need this much lift? Are you lifting such massive stages or sending them so far out into the cosmos that you really need to cluster them like that? Doesn't really matter in this game how powerful something is unless it its infinite. Sandbox it doesn't matter period, career you'd cripple yourself putting so many of these in an expendable rocket.

[spikeyhat09]

The question is' date=' why?

Do you need this much lift? Are you lifting such massive stages or sending them so far out into the cosmos that you really need to cluster them like that? Doesn't really matter in this game how powerful something is unless it its infinite. Sandbox it doesn't matter period, career you'd cripple yourself putting so many of these in an expendable rocket.[/quote']

I suppose this vaguely resembles the mechjeb argument. Since it is a single player game, it isnt all that important that each part be good relative to its peers, so long as the player is having fun. I guess I'm just not used to colossal projects becoming so numbingly easy, but who says that's a bad thing?

[GoSlash27]

I suppose this vaguely resembles the mechjeb argument. Since it is a single player game, it isnt all that important that each part be good relative to its peers, so long as the player is having fun. I guess I'm just not used to colossal projects becoming so numbingly easy, but who says that's a bad thing?

spikeyhat09,

Who says that this engine *isn't* good relative to it's peers, and how do you define that?

Best,

-Slashy

[spikeyhat09]

spikeyhat09,

Who says that this engine *isn't* good relative to it's peers, and how do you define that?

Best,

-Slashy

you know, like each part having strengths and weaknesses. the classic example of balancing harmony are the LV T45 and the LV T30. one gives you high TWR and thrust, one gives you control. its this virtual yin and yang that make or break balance in not just ksp but any game really. the new engine gives you all strength and no weakness, but who am i to complain if people are having fun? hell, i had a blast building that station and will certainly build more like it.

[Claw]

Well, it's 1/4 the size of the thing that is 4x bigger than it? It has pretty much 1/4 of the trust of the KS-25x4, with slightly more than 1/4 of the mass (despite the KS-25x4 having way more volume to it's model). The only exception being that you can surface mount it, which you could have done anyway with other parts had it been stack attach only.

Where it's really better is that huge gimbal range, which (unfortunately) the SAS sometimes has a hard time dealing with it.

Also, the game doesn't do aero occlusion for surface mounted parts (so more drag). Plus the thing costs nearly 50% of the KS-25x4.

A simple test I ran (launching a single S3-3600 straight up) with a single KS-25x4 resulted in the 1,440 m/s and an AP of ~84km. While 4 of the KS-25s only reached 1,313m/s and an AP of ~64km. And a single Rhino out-performed both of those with a top speed of 1,842m/s and an AP of ~262km. That was all in-atmosphere, but remember that there's a weight penalty for using 4x KS-25s instead of a single KS-25x4 (which doesn't make a good interplanetary drive anyway).

I too felt it was a bit OP when I first saw it, but after some comparison, I think that initial reaction was mostly swayed by it's small size 1 form factor, from a size 3-ish capable part.

Cheers,

~Claw

[Kerbart]

(...)Im not trying to hark on rocketdyne or anything but I do feel an obligation to point out things that appear to be issues. at least with the hope that they receive a second look.

Well let's be honest... the F-1 was indeed hopelessly OP.

[ZooNamedGames]

In my opinion, and my only critique is that the TWR may be a bit high, because I ran into the same issue earlier. I tried to make a F9R Dragon style launcher using the KS-25s as the Merlin MEs and the TWR (from a 1.0.4 KE) was reading almost 4. So I stacked the fuel as high as the VAB could let me, and the TWR was still 3.5+. Noting I was using 9 (as per the Falcon 9). But I feel I shouldn't have to use a SLS sized vehicle to accompany the same TWR of the real thing. That would be like using the Titan II's MEs to launch the S5. Granted, 9 engines may be a bit overkill for that size payload, so I get that flaw so I can't complain too much. The real complaint is that there has to be a limit on power. Since when this new engine starts to compete with what was the king of all rocket engines in a 1.25m size? That's a bit off. I feel the TWR ratio should be nerfed a tad bit. Simply because using 27 of these to launch a Dragon V2 would not only put it into LKO, but Jool without needing a second stage. I understand the cost, but I'm focusing sandbox mostly but even for the sake of argument- if you were to use this in a career mode, using this to punch through the majority of the atmosphere and coast high enough, you could do a SpaceX Falcon9 landing easily and recover these boasters while deploying your massive science interplanetary space carriers. I haven't had 1.0.5 for 5 hours yet and I've come up with at least 8 concepts on how to use and recover these engines in a very OP manner. They're just too one size fits all... And ironically that statement also works literally as its only a 1.25!

Again to reiterate- I am aware of the cost, what it's derived from, it's TWR and everything. I have read the last few pages.

[Geher]

I agree that it is overpowered. I was expecting the Vector to be a medium-sized Skipper (650 kN, maybe a little bit more) with more gimbal.

I think they should make it less powerful, and therefore add more powerful large-sized SRB's.

Because right now I have to use multiple SRB's for my STS-like craft (didn't change it to work with the new vector engine yet).

[problemecium]

Meh. I'm not surprised about this at all. The same thing happened when Kerbodyne parts were introduced, and they were nerfed in the next update. More likely than not, this will be too.

[More Boosters]

valid points. as a sandbox player, i often overlook factors that influence that mode of gameplay. with this in mind, and acknowledging a certain level of reductio ad absurdum in my OP, i still maintain that this particular part might be a little too good. you are correct about the TWR - it is the same as the mainsail. however, especially for 1.25m parts, gimballed rockets come with a hit to TWR. this particular part not only has vastly more gimbal range than any other main rocket engine, but also has very good TWR, like the mainsail. This, combined with markedly above average efficiency at both sea level and in vacuum, and the increased versatility that comes with smaller sized parts, all contribute to this engine being, in my opinion, at least a tier above any other primary rocket engine.

not to mention that clustering mainsails in the same manner kills your aerodynamics

The reason Vector seems too good for a 1.25m part is that 1.25m parts aren't good enough for 1.25m parts in general. I'm looking at you Swivel, and Reliant. Reliant simply doesn't give that "high TWR and thrust" you mentioned. Heck, if you add AV-R8 (at least two and only if you're moving in one direction, 3 if you want full coverage) to compensate for its lack of gimbal, it's worse than the Swivel, which isn't doing wonders to begin with.

Edited November 11, 2015 by More Boosters

[GoSlash27]

you know, like each part having strengths and weaknesses. the classic example of balancing harmony are the LV T45 and the LV T30. one gives you high TWR and thrust, one gives you control. its this virtual yin and yang that make or break balance in not just ksp but any game really. the new engine gives you all strength and no weakness, but who am i to complain if people are having fun? hell, i had a blast building that station and will certainly build more like it.

spikeyhat09,

I'm with Claw on this. It's not really OP when compared to it's neighbors. It's heavy and expensive. You get crazy thrust if you spam a bunch of them, but that's true for every engine.

Best,

-Slashy

[KerbMav]

Hm, does the Vector - building and clipping issues aside - in any way outclass five Swivels?

Wiki is not yet updated and cannot find the values anywhere right now.

[Whirligig Girl]

...All of the 2.5m parts have gimbals on them, so I don't know where you're getting the idea that there's a good comparison to added weight for them there. As for the rest of the stuff, keep in mind that this engine is a non-clustered version of the 4x KS-25 Mammoth cluster... which has a stupidly high TWR and is ultimately a better engine to bring along for most heavy-lift situations.

And as for aerodynamics, they're so much weaker than they were prior to 1.0 that there's no reason to even consider them during a launch. The dV losses to drag are going to stay around 100 m/s at most.

Frankly, I agree that its smaller size is a benefit. I wish all stock engines could do away with the tankbutts; the Mainsail could be half as wide, as could the Skipper. The LV-909 should also be able to be fitted in more places. The problem is that you're attacking it from the wrong angle: all engines should be that flexible, not the other way around.

"You must spread some Reputation around before giving it to ferram4 again."

Squad, listen to Ferram. He has some pretty neato ideas.

[GoSlash27]

Hm, does the Vector - building and clipping issues aside - in any way outclass five Swivels?

Wiki is not yet updated and cannot find the values anywhere right now.

KerbMav,

The Vector has a slight advantage in Isp and weighs a little over half what 5 Swivels would weigh, but costs 3 times as much.

A better comparison would be the Skipper or Mainsail.

Type: Thrust,Mass, Isp, Cost

Skipper: 650kN, 3t, 280-320s, $5,300

Vector: 1,000kN, 4t, 295-315s, $18,000

Mainsail: 1,500kN, 6t, 285-310s, $13,000

Best,

-Slashy

[KerbMav]

Thanks Slashy!

But I kinda disagree because of the fact the whole discussion revolves about it being an allegedly overpowered 1.25m engine or not?

Edit: Ah, wiki has updated!

It also has a fantastic 20m/s impact tolerance ...

Edited November 11, 2015 by KerbMav

[Geher]

Thanks Slashy!

But I kinda disagree because of the fact the whole discussion revolves about it being an allegedly overpowered 1.25m engine or not?

Edit: Ah, wiki has updated!

It also has a fantastic 20m/s impact tolerance ...

Yes, the real question should be if it is overpowered for a Mk3 STS.

And I don't even know if it is. Maybe it just works perfectly when only using only one Kickback SRB on each site.

I'll definitely try that out.

[GoSlash27]

Thanks Slashy!

But I kinda disagree because of the fact the whole discussion revolves about it being an allegedly overpowered 1.25m engine or not?

KerbMav,

That's judging it by the wrong criteria IMO. You *could* build a Mk1 lifter with it, but the fuel required would necessitate an excessively tall noodly stack. A practical lifter design using this engine is going to use at least Rockomax tanks.

Yes, the real question should be if it is overpowered for a Mk3 STS.

And I don't even know if it is. Maybe it just works perfectly when only using only one Kickback SRB on each site.

I'll definitely try that out.

Geher,

My 1.04 shuttle used 3 skippers and 2 KD-25K boosters and it was just enough to work with a reasonable payload. The Vector has better Isp and almost twice the thrust, so yeah it's a bit OP. This is probably a good thing though since it will make shuttles more accessible.

Best,

-Slashy

[NecroBones]

I've been arguing for a long time that the 1.25m engines effectively become nothing more than lander engines, once you're past a certain point in the tech tree (or playing sandbox), since they're really weak compared to larger diameter engines. I always wanted the option of building radial boosters with them that contribute well to larger stack, but we just didn't have that capability without needing to spam a crap-ton of them onto the rocket design, rather than using a much smaller number of 2.5m booster stacks.

The thing I did in SpaceY, though, was to make a 1.25m engine that bridges the gap between the Swivel/Reliant engines and the Skipper, rather than between the Skipper and Mainsail.

I don't dislike the Vector (actually I think it's going to fill a wonderful niche for shuttles and the like, and its quite pretty), but I'm wondering if it would have made more sense to aim for the 800 thrust range, rather than 1000. The counter-argument I would use on that however, is that it's always bothered me when we have engine clusters with a certain level of performance, but can't get access to the individual engines with matching stats. (Again, SpaceY addressed that by making sure you could always get the engine singles, with the correct fractional stats).

So I'm a bit ambivalent.

Something I would love to see now is a redesign of the Mammoth to use the new Vector artwork for the bells.

[ZooNamedGames]

Thanks Slashy!

But I kinda disagree because of the fact the whole discussion revolves about it being an allegedly overpowered 1.25m engine or not?

Edit: Ah, wiki has updated!

It also has a fantastic 20m/s impact tolerance ...

Oh and tested something- the fantastic gimballing range of the engine allows it to bounce, stick and stutter while being dragged across the ground adding to it's strength.

- - - Updated - - -

Something I would love to see now is a redesign of the Mammoth to use the new Vector artwork for the bells.

Agreed!

[KerbMav]

You *could* build a Mk1 lifter with it, but the fuel required would necessitate an excessively tall noodly stack. A practical lifter design using this engine is going to use at least Rockomax tanks.

Point taken.

[ZooNamedGames]

As mentioned earlier I already have several concepts for launching LKO payloads while reusing the engines. Not all of them needing for them to be constantly managed. I even have considered to recover them SS-SRB style.

[Frozen_Heart]

People are missing the point with this engine. It has to be a 1.25m engine for 3 to fit on the back of the shuttle. Otherwise we could just use 3 Skippers and have tank butts twice as wide as the actual vehicle. It worked but was ugly. I do agree that its thrust should be scaled down to somewhere between 600 - 650 ASL. We do need proper SRBs though rather than the toy ones we have atm. To get performance closer to the real shuttle i'm having to use 8 of the largest ones.

I think that this part is highlighting how weird KSPs parts are balanced. To made a space shuttle it requires parts that are completely out of balance with everything else, even accounting for Kerbins small scale.

Edited November 11, 2015 by Frozen_Heart

[ZooNamedGames]

People are missing the point with this engine. It has to be a 1.25m engine for 3 to fit on the back of the shuttle. Otherwise we could just use 3 Skippers and have tank butts twice as wide as the actual vehicle. It worked but was ugly. I do agree that its thrust should be scaled down to somewhere between 600 - 650 ASL.

I think that this part is highlighting how weird KSPs parts are balanced. To made a space shuttle it requires parts that are completely out of balance with everything else, even accounting for Kerbins small scale.

In that respect, its the greatest part to exist for shuttle makers.

Yeah, shuttle's have always been a challenge. If someone thinks they are hard to make now then they have never seen how bad it was in .19 when I first joined.