Engines revamp - Thrust and performance changes discussion

[passinglurker]

3 hours ago, Tweeker said:

I understand where the throat is, thank you.

The problem is in the term "tankbutt" I haven't ever seen that  outside of KSP. I think it is more accurate to call the area above the powerhead, and the thrust structure. By call it "tankbutt" instead many people try to make the case that it is part of the tank, and therefore ok to remove.

if you want to brush off a staff member and the dev of realism overhaul then clearly there is no point accommodating you.

3 hours ago, Tweeker said:

That is, however not the case, for a couple of reasons,  First, In KSP the tanks do not protrude  out of the ends

I'm sorry when did you become a dev and decide what fuel tanks do?

3 hours ago, Tweeker said:

second even on the Saturn's upper stage this isn't the case

cutaway schematics or it didn't happen.

 

3 hours ago, Tweeker said:

The fuel tank ends about where the helium tanks are

helium tanks are still tankage since you want to be so nit picky

3 hours ago, Tweeker said:

(I apologize if I am being patronizing here , but people repeatedly insist that this are is fuel tank butt of the fuel tank.)

don't worry... this won't make them stop...

3 hours ago, Tweeker said:

The  new Rhino  is taller, and might be even better, but the compact version is the cutoff at the powerhead,

no its not you just suck at identifying what is the powerhead. seriously get your eyes checked.

3 hours ago, Tweeker said:

and does not include any provision for the thrust structure.

its not being mounted to a wider diameter so the big pyramid "trust structure" (as you call it) tankbutt isn't needed to reach the lode bearing outer edges of the tank

3 hours ago, Tweeker said:

or interconnects which would take up space above the engine. such as in the 2nd stage of the Saturn,

have you seen the new fuel flow mechanics? kerbal values creative freedom over your obsession with pipes.

3 hours ago, Tweeker said:

The power head needs to be at least 33% taller, or It needs to be wider, or the power head needs to be offset to one side.

Here take this this this and this and lets see you do any better modeling an engine.

3 hours ago, Tweeker said:

As far as the rest of the engines rest of the engines go,  I don't think a new art pass is needed, and I don't like the art I have seen.

You know nothing of art, rocket science, or engineering then, and your critiques are unqualified and unwanted please go back to playing minecraft.

3 hours ago, Tweeker said:

Some of the new engines seem a bit redundant, the 303 for example is almost exactly on top of the spark, thrust wise, It seems like the Isp will make it more space tuned, But still it is too close to the spark's niche.

you know they can and will change and refine the balance right? nothing is going to be redundant @NathanKell already told you not to put stock into the stats.

4 hours ago, Tweeker said:

For a longtime this was my main complaint about the LV-T 30 & T 45. They where essentially snow clones of each other I am glad you are pushing the farther apart, and very glad that one of them is is being pushed up to the 300 kN range. I am not entirely sold on the LV-T 15, It makes sense that it is  a fractional size of the other 2 engines, but the ISP wise the quoted stats are extremely bad. 

@NathanKell said the stats aren't final they haven't had a chance to test these parts, but your input probably isn't wanted squad would be looking at the balance as a whole whereas short sighted change fearing nitpickers like you only obsess about tiny pieces that won't fit together properly after you finish filing them down.

4 hours ago, Tweeker said:

I wish you would ditch the  Twin Boar and Mammoth entirely, and replace them with a bi- and quad- adapter, and add more adapters as well, maybe a 5 way for Apollo type applications, I think having adapters that you could mount whichever engine you choose, would be much more versatile than having dedicated dual and quad engines.

I wish you would stop inflating my part count with your nonsense no one needs adapters when you can just surface attach compact mode engines that is infinitely more versatile than adapters. due to the limits of how big engines can realistically be made there is nothing wrong with having multi nozzle engines.

4 hours ago, Tweeker said:

The poodle really needs a buff, it's main problem is the way it relates to the 2.5m parts,  While the poodle can be viewed as basically a 4X version of the LV-909, the other the equivilant parts don't follow this trend,. The small fuel tank in the 2.5m range is 9X heavier,  The capsule is  5X heavier, The lander can is  the best of the bunch at being just over 4X heavier than the 1.25m version. The result of this is that it's TWR in a stack moves in a very granular way. If it was 50% -60% larger it would give you a lot finer adjustment.  Buffing the LV-909s thrust will make the poodle shortcomings that much more obvious. Consider tweaking the poodle instead.

More nonsense nitpicky ramblings that won't matter cause they are giving kerbal its first real ballance pass with the revamp update so the mass of all these 2.5m parts you mention will change.

4 hours ago, Tweeker said:

One last thought I had while writing this, It would be fantastic if the engines could serve as size adapters like the J-2 in between  the Saturn II and the Saturn IV-B stages.

finally something we can agr-

4 hours ago, Tweeker said:

I would like that WAY more than having boattail/bare vesions of engines.

-aaaaaand you had to go and ruin it with your rude ungratefulness.

4 hours ago, Tweeker said:

And finally sorry for going on so much.

great how about the apology for being wrong and ungrateful?

[Araym]

1 hour ago, passinglurker said:

~snip~

Here take this this this and this and lets see you do any better modeling an engine.

~snip~

 

+1 Vote and immediately what I thougth about so "orthodox realism criticism" about a fun game about little green men going space from their tiny planet!!!

But could I add a note on that advice???

"If you do not like KSP as it is not realistic, go there too"

Edited September 17, 2016 by Araym

[regex]

6 hours ago, Tweeker said:

The problem is in the term "tankbutt" I haven't ever seen that  outside of KSP. I think it is more accurate to call the area above the powerhead, and the thrust structure. By call it "tankbutt" instead many people try to make the case that it is part of the tank, and therefore ok to remove.

Well, it is the tankbutt. The liquid oxygen tank extends slightly into that area on the S-IVb. It's true that there is thrust bracing up there but there's no reason that can't be reconfigured to fit a smaller or larger tank structure. 

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The  new Rhino  is taller, and might be even better, but the compact version is the cutoff at the powerhead,

No, it isn't, it has a smaller thrust structure/bracing above it, making it compact. The important bit of the thrust structure that connects the combustion chamber to the actual structure, the part I highlighted in purple in my example, is the same on both the compact and the large Rhino.

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and does not include any provision for the thrust structure.

It does, it's just a smaller structure because that is not a part of the engine, but instead a part of the tanks.

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or interconnects which would take up space above the engine. such as in the 2nd stage of the Saturn,

2nd stage has five engines, and if the player decides on that for their own rocket within KSP there are plenty of other parts to string one up with.

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The power head does not mount directly to the bottom of the tank.

Correct, there's a little bit of thrust structure above the combustion chamber that attaches to the structure of the tanks and rocket. The actual bracing belongs on the rocket itself because it is dependent on tank size and aerodynamic requirements.

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The vector, even the new one is even worse, the powerhead in the compact model is too short;

It's not, it actually conceals the powerhead behind a fairing to make it look more like the SSME when install on the actual STS. Line them up side-by-side and nothing is missing.

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One last thought I had while writing this, It would be fantastic if the engines could serve as size adapters like the J-2 in between  the Saturn II and the Saturn IV-B stages. I would like that WAY more than having boattail/bare vesions of engines.

This is what the "compact" engines are for, making clusters like the S-II.

Edited September 17, 2016 by regex

[Frozen_Heart]

I'm not sure why people think you can't have engines with a giant circle matching the size of the fuel tank under each one. The Falcon 9 and the Space Shuttle don't have several huge circles sticking out from their sides.

 

The reason that the machinery is hidden on the Vector, and compact versions of the engines are being made, is due to aesthetics. It allows clustered engines to look good as the ends of the engines can't change themselves to fit anything the player will come up with. Engines clusters and hidden machinery are clearly possible in real life, so stopping them looking good in KSP to give every engine a thrust structure the size of the entire fuel tank end will stop many possible designs in KSP.

[Gaarst]

18 minutes ago, Frozen_Heart said:

I'm not sure why people think you can't have engines with a giant circle matching the size of the fuel tank under each one. The Falcon 9 and the Space Shuttle don't have several huge circles sticking out from their sides.

 

The reason that the machinery is hidden on the Vector, and compact versions of the engines are being made, is due to aesthetics. It allows clustered engines to look good as the ends of the engines can't change themselves to fit anything the player will come up with. Engines clusters and hidden machinery are clearly possible in real life, so stopping them looking good in KSP to give every engine a thrust structure the size of the entire fuel tank end will stop many possible designs in KSP.

This ^

Also, who even cares if engines having machinery is realistic or not? If you want realism you will clip the engines inside another part to only let the nozzle out because no rocket has all the pipes n stuff hanging out. In both cases you don't see the machinery from the outside.

Edited September 17, 2016 by Gaarst
Typos

[regex]

16 minutes ago, Frozen_Heart said:

Engines clusters and hidden machinery are clearly possible in real life, so stopping them looking good in KSP to give every engine a thrust structure the size of the entire fuel tank end will stop many possible designs in KSP.

But ... but ... but that would be cheating! Clearly the engines are supposed to fit only on certain sizes of tanks!

[Tweeker]

On ‎9‎/‎17‎/‎2016 at 3:51 PM, regex said:

But ... but ... but that would be cheating! Clearly the engines are supposed to fit only on certain sizes of tanks!

Nobody said that,

 

On ‎9‎/‎17‎/‎2016 at 3:33 PM, Frozen_Heart said:

I'm not sure why people think you can't have engines with a giant circle matching the size of the fuel tank under each one. The Falcon 9 and the Space Shuttle don't have several huge circles sticking out from their sides.

 

The reason that the machinery is hidden on the Vector, and compact versions of the engines are being made, is due to aesthetics. It allows clustered engines to look good as the ends of the engines can't change themselves to fit anything the player will come up with. Engines clusters and hidden machinery are clearly possible in real life, so stopping them looking good in KSP to give every engine a thrust structure the size of the entire fuel tank end will stop many possible designs in KSP.

Or that the engine is only intended for certain size tanks, But what I am saying is that the compact version of the Rhino, and Vector is too compact.

The top of the compact version needs to be taller, and wider.

 

[Frozen_Heart]

27 minutes ago, Tweeker said:

Nobody said that,

 

Or that the engine is only intended for certain size tanks, But what I am saying is that the compact version of the Rhino, and Vector is too compact.

 

The top of the compact version needs to be taller, and wider.

 

Engines shouldn't be forced onto certain sized tanks though. You should be able to use them on anything. Real life engines aren't forced to be used on only one tank size.

 

Also with engines like the Vector the machinery is supposed to be hidden inside the shuttle, which is why it was omitted. The real life shuttle only has the nozzles showing. That engine was added pretty much purely due to there being no engine suitable for building one. The Rhino could also easily have some of its machinery hidden. The fuel tank ends are even slightly hollow so you can just assume it is in there.

[passinglurker]

28 minutes ago, Tweeker said:

But what I am saying is that the compact version of the Rhino, and Vector is too compact.

The top of the compact version needs to be taller, and wider.

and what the rest of the thread has been telling you... repeatedly... is that They are not too compact while these alluded to and are inspired by real world rocket engines these are not scale models just like how kerbin is not a scale model of our solar system. 

[regex]

1 hour ago, Tweeker said:

You are assuming that the KSP engines are exact copies of the IRL engines. They are not. They are inspired by IRL engines but are Kerbal engines first and foremost. Given that, you can easily see how the engines make perfect sense as they are. If you want accurate depictions of real engines there are several mods that fit the bill.

[Tweeker]

2 hours ago, regex said:

You are assuming that the KSP engines are exact copies of the IRL engines. They are not. They are inspired by IRL engines but are Kerbal engines first and foremost. Given that, you can easily see how the engines make perfect sense as they are. If you want accurate depictions of real engines there are several mods that fit the bill.

I'm not saying over-haul the engines to make them hyper-real. I'm not advocating changes to any of the existing engines.  {except the vector}  What I am saying is that the changes you advocate would make the KSP engine less realistic.

You want to be able to cluster engines as is done IRL. Which Is great, but the top of the engines are cut down too much. The engine can't be any shorter than the power head plus the gimbal. The top of the engine don't need to be any narrower than the width of the engine bell,

otherwise you will part of the engine sticking out past the  tank you are clustering it under.

Or if it is an upper stage it will be sticking out of the side of the stack.  

 

[Tweeker]

3 hours ago, Frozen_Heart said:

Engines shouldn't be forced onto certain sized tanks though. You should be able to use them on anything. Real life engines aren't forced to be used on only one tank size.

For the second time, nobody is saying each engine must only be paired with a certain sized tank.

3 hours ago, Frozen_Heart said:

Engines shouldn't be forced onto certain sized tanks though. You should be able to use them on anything. Real life engines aren't forced to be used on only one tank size.

 

Also with engines like the Vector the machinery is supposed to be hidden inside the shuttle, which is why it was omitted. The real life shuttle only has the nozzles showing. That engine was added pretty much purely due to there being no engine suitable for building one. The Rhino could also easily have some of its machinery hidden. The fuel tank ends are even slightly hollow so you can just assume it is in there.

     The vector really is the genesis of the whole problem, It does not act like the other engines. Instead of representing the machinery as being present on top of the nozzle it is assumed to exist somewhere else. As long as it is only used only on the shuttle it is not a problem. anywhere else it doesn't function in the same way as the other rocket engines. Instead of fixing the problem, {the vector} you want to re-make all the other engines in this mold.

     It would be very simple to fix the vector, and it wouldn't break the shuttle to do it.

   1) add the machinery to the top of the vector.

    2) make the mounting plate so that any engine you mount on it is recessed so the power head is hidden.  

     

[regex]

 

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You want to be able to cluster engines as is done IRL. Which Is great, but the top of the engines are cut down too much.

No, they're not. This has been explained many times.

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The engine can't be any shorter than the power head plus the gimbal.

Fortunately that's not the case.

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The top of the engine don't need to be any narrower than the width of the engine bell,

It can be as narrow as desired provided that is mechanically possible

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otherwise you will part of the engine sticking out past the  tank you are clustering it under.

So now width is an issue? I feel like you're just trying to find anything wrong with these engines you can. 

Judging from the pictures the base of the compact Rhino is slightly smaller than 2.5m (but bigger than 1.25m) with the bell being about 2.5m or slightly smaller. This will never result in the width issue you're now bringing up unless the user is clipping parts, in which case they don't care one whit what you think. And anyway, who cares if someone slaps a Rhino on a 1.25m stack with a huge bell? If it offends you so much, don't do it, there are far more appropriate engines and that doesn't make the engine unrealistic, it makes the resulting rocket unrealistic.

Go play RO/RSS like I do if you need to be penalized for that.

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Or if it is an upper stage it will be sticking out of the side of the stack.

What if the stack is larger on the lower stage?

3 minutes ago, Tweeker said:

The vector really is the genesis of the whole problem, It does not act like the other engines. Instead of representing the machinery as being present on top of the nozzle it is assumed to exist somewhere else.

No, this has been explained, the machinery is behind the fairing. Line it up with the bare Vector and it comes out fine.

Edited September 19, 2016 by regex

[NathanKell]

On 9/16/2016 at 10:03 PM, NoMrBond said:

Ungoof it, carpe jugulum!

I suggest 256-290, for... uhh, no reason in particular. /cough

Jugulum carped.

Not quite an H-1, though.

[NoMrBond]

1 minute ago, NathanKell said:

Jugulum carped.

Not quite an H-1, though.

I was thinking of the XLR87/LR87-3 for some reason instead of the H-1

H-1 is nice because you get S-3D to X-1 to H-1 to RS-27, uhh... I guess that's not really applicable to stock 

[Tweeker]

5 hours ago, regex said:

Fortunately that's not the case.

It can be as narrow as desired provided that is mechanically possible

So now width is an issue? I feel like you're just trying to find anything wrong with these engines you can. 

Judging from the pictures the base of the compact Rhino is slightly smaller than 2.5m (but bigger than 1.25m) with the bell being about 2.5m or slightly smaller. This will never result in the width issue you're now bringing up unless the user is clipping parts, in which case they don't care one whit what you think. And anyway, who cares if someone slaps a Rhino on a 1.25m stack with a huge bell? If it offends you so much, don't do it, there are far more appropriate engines and that doesn't make the engine unrealistic, it makes the resulting rocket unrealistic.

Go play RO/RSS like I do if you need to be penalized for that.

What if the stack is larger on the lower stage?

No, this has been explained, the machinery is behind the fairing. Line it up with the bare Vector and it comes out fine.

Once again, This is not about putting large diameter engine bells under smaller stacks. It is about how these engine behave when clustered. look at the mammoth:

The engine bell, and powerhead if you could see it, would stick out past the edge of the tank {blue line}, There is a fairing that covers the powerhead, {red line} and it almost inline with the engine bell.  There is no need to cut the engine any further.

Here you can see the result if you cut the Vector "only" to the edges of the engine bell  

Not much difference

And if you cluster entirely under the tank there is, once again, no issue.

 

So tell me, why does the powerhead  need to be  cut down more than this?

[Kobymaru]

On 16.9.2016 at 2:40 PM, Sharpy said:

Let me remind you:

 

First, the CoM of the engines has always been further in front of the exhaust, seemingly "in the air", where the turbine is supposed to go.

Second, might I remind you:

This *HAS* been almost fixed for 1.1, but a very very vocal minority of people (ermahgerd, mah VTOL's) got the feature killed. I'm still sad about that.

[Red Iron Crown]

1 minute ago, Kobymaru said:

First, the CoM of the engines has always been further in front of the exhaust, seemingly "in the air", where the turbine is supposed to go.

Not always, that was a 1.0.x change IIRC.

1 minute ago, Kobymaru said:

This *HAS* been almost fixed for 1.1, but a very very vocal minority of people (ermahgerd, mah VTOL's) got the feature killed. I'm still sad about that.

I'll avoid asking for a citation of "minority" but instead point out that the feature is still there in game, just waiting to be turned on in the cfgs if you want it. I believe there is a ModuleManager script around for it if you'd rather not do it by hand.

[KerikBalm]

I'm curious how that turbine thing is supposed to work... do you only place those in hollow structural fusalages? do you make the part larger, and a shroud gets added around the turbine when you put something on in front of the engine?

As far as I understood, those parts could still be added just the same as engines before - the attachment node location wasn't change - with the turbine disappearing when the part was attached, or with the turbine clipping into the part in front of it... no?

[Red Iron Crown]

6 minutes ago, KerikBalm said:

I'm curious how that turbine thing is supposed to work... do you only place those in hollow structural fusalages? do you make the part larger, and a shroud gets added around the turbine when you put something on in front of the engine?

As far as I understood, those parts could still be added just the same as engines before - the attachment node location wasn't change - with the turbine disappearing when the part was attached, or with the turbine clipping into the part in front of it... no?

It's a visual mesh with no collider, so it just clips into whatever's in front of it harmlessly. Functionally the part is exactly the same, it just has this "ghost" turbine added to the front.

[John FX]

On 16/09/2016 at 7:18 PM, Temeter said:

Btw, in case someone is still confused about how what's engines and what's the tankbutt, this pictures shows it quite nicely:

I like the way they say `modern computers` have 100 times as much memory as the Apollo computer as that`s about 3Mb. Most people playing KSP have 100,000 times as much memory (3Gb)

 

Myself I am happy there is a 100Kn engine for landers now, it`s been missing for years.

[regex]

 

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So tell me, why does the powerhead  need to be  cut down more than this?

It hasn't been cut down. At all. In any case with a compact engine. You're literally imagining things.

[Frozen_Heart]

3 hours ago, Kobymaru said:

First, the CoM of the engines has always been further in front of the exhaust, seemingly "in the air", where the turbine is supposed to go.

Second, might I remind you:

 

This *HAS* been almost fixed for 1.1, but a very very vocal minority of people (ermahgerd, mah VTOL's) got the feature killed. I'm still sad about that.

I wouldn't have minded this is an actual jet VTOL engine had been added, either like the harrier nozzles or an F-35 turbofan. If one of those was in game then the other jets could have the compressors and turbines added and it would have been fine.

Jet VTOLs are possible in real life, so why stop them being built in KSP?

 

Likewise, I wouldn't mind certain rockets like the Vector having the full machinery if it clipped into the tank and was hidden, as that is how many engines are in real life.

Edited September 19, 2016 by Frozen_Heart

[regex]

12 minutes ago, Frozen_Heart said:

Likewise, I wouldn't mind certain rockets like the Vector having the full machinery if it clipped into the tank and was hidden, as that is how many engines are in real life.

That's why we have proposed engines with boat tails, so we can achieve that look without unrealistically clipping the engine into the tank like real life engines don't. The compact and bare engines are good for people who want to see some detail or want to get artsy with their designs.

[KerikBalm]

I wouldn't mind if all jet engines were like the goliath or the nuclear thermal turbojet from atomic age. You don't have a huge fuel tank between the intake of an engine and its exhaust...

but I hate part clipping abuse. I'm often tempted to stick structural fusalages in front of my jet engiens for "realism"... but then the added dry mass also sets off something in my head saying "its just dead weight, get rid of it". I wouldn't mind if jet engines became much longer, but I wouldn't be super excited about a dry mass increase.

I would absolutely love a VTOL jet engine.. and it seems like it should be easy to do in KSP.

Consider the goliath with its thrust reverser - toggle the engine mode and the thrust points in a different direction... 180 degrees from where it was. We just need this to be 90 instead of 180, and a different animation (nozzles swiveling). It would be really great if we could also adjsut this with a slider like the cargo ramp... but unless that slider moved for all parts placed with symmettry, it would be quite hard to use more than one of these engines.

Now that I think about it... surely someone has made a mod for an engine like that?

Links anyone?