Rapier closed cycle, OP or in need of a Buff?

[Reinhart Mk.1]

On 7/4/2019 at 12:07 PM, Xavven said:

To answer OP's original question, no I don't think the RAPIER needs a buff. It's already the best engine in the stock game for SSTO launches. It outperforms the whiplash in airbreathing mode, as it has more thrust and operates at higher altitudes, and on top of that it has great thrust in closed cycle. In my most recent spaceplane design, whiplashes + swivels could not get me to orbit in a single stage, but all-RAPIERs did so extremely easily.

saaaaaaame, im now reluctant to put whiplashes on my SSTOs unless they ABSOLUTELY need them

[fulgur]

I tried to make a Whiplash/Dart SSTO for a challenge. Ended up in orbit with 150m/s dV. That is why I love RAPIERs.

[IronMaiden]

13 hours ago, Incarnation of Chaos said:

Note i don't want the RAPIER it's self made more powerful; that would the job of a entirely new part. But i would like to move it down one node; because by the time you get it you're launching 3.75/2.5M rockets and can make them fully reusable. Payload fractions aren't important; i can build a fully reusable rocket that's larger in a tenth of the time it takes to fine-tune an SSTO and get the same payload to orbit and the same reusablity.  And 900 ton rockets don't really mean anything to me at this point; i was launching 2-300 ton stacks of asparagus to the moon and minmus in my current career save after only a week or 2 (The entire stack weighed about 300 tons; what made it to the mun was around 30-60 tons). And i frequently exceed the megaton range now ; fuel is silly cheap compared to engines/crew and reuse means essentially i'm only paying fuel costs.

That being said i find your arguement in favor of the Panther interesting; pushing whiplashes to Mach 1 wastes a lot of fuel before hitting the efficiency curve where they're actually doing work. Panthers would start out decent and only get better before flaming out; i may be running some tests fairly soon because of you xD.

I'm all for new parts  However, moving it down one node would put it on the same tier as the Whiplash, which would severely devalue it. If there's any one part in the game deserving of the highest tier, 1000 science node, it's the RAPIER. It combines incredible versatility with far superior atmospheric performance. It single-handedly makes one of the more difficult destinations in the game, Laythe, a joke. Yeah you can make a rocket that will get the same size payload to orbit quicker and easier, but you get into making SSTOs for a reason, the coolness, the reusability, the efficiency, etc. Payload fraction matters if you want it to matter, since you talked about saving mass in your original comment I assumed it mattered to you as well. Traditional rockets can't hold a candle to cargo space planes when it comes to saving mass.

Yeah, the only reason you're using Whiplashes in the first place is because they're better than RAPIERs at low speeds, so why not use the best low speed engine?  I came to that conclusion when building this SSTO, good luck and have fun with your own experiments!

Edited July 28, 2019 by IronMaiden
grammar

[Incarnation of Chaos]

8 hours ago, IronMaiden said:

I'm all for new parts  However, moving it down one node would put it on the same tier as the Whiplash, which would severely devalue it. If there's any one part in the game deserving of the highest tier, 1000 science node, it's the RAPIER. It combines incredible versatility with far superior atmospheric performance. It single-handedly makes one of the more difficult destinations in the game, Laythe, a joke. Yeah you can make a rocket that will get the same size payload to orbit quicker and easier, but you get into making SSTOs for a reason, the coolness, the reusability, the efficiency, etc. Payload fraction matters if you want it to matter, since you talked about saving mass in your original comment I assumed it mattered to you as well. Traditional rockets can't hold a candle to cargo space planes when it comes to saving mass.

Yeah, the only reason you're using Whiplashes in the first place is because they're better than RAPIERs at low speeds, so why not use the best low speed engine?  I came to that conclusion when building this SSTO, good luck and have fun with your own experiments!

Fair enough then.

[kerbnub]

Agree that the low vacuum ISP makes no sense from a realism standpoint: they should be optimized for vacuum, as they're not meant for use at low altitudes. But for stock gameplay balance, they're in a good place, as SSTOs are already OP as far as mass fractions to orbit are concerned.

While the low ISP really hurts at higher scales (2.5x and trying in JNSQ, which is 2.7x), I've found them to still result in overall fairly realistic feeling SSTOs. It compensates in a way for the fact that real concepts for SSTOs have to use rocket mode for most of their ascent. Skylon gets to 1550 m/s airbreathing,  while LKO orbital speed is about 7.8 km/s. Optimized SSTOs can still getting you to orbit with a higher mass fraction than rockets, it's just not so easy to build an SSTA.

[Empiro]

On 7/27/2019 at 9:37 PM, Incarnation of Chaos said:

Note i don't want the RAPIER it's self made more powerful; that would the job of a entirely new part. But i would like to move it down one node; because by the time you get it you're launching 3.75/2.5M rockets and can make them fully reusable. Payload fractions aren't important; i can build a fully reusable rocket that's larger in a tenth of the time it takes to fine-tune an SSTO and get the same payload to orbit and the same reusablity.  And 900 ton rockets don't really mean anything to me at this point; i was launching 2-300 ton stacks of asparagus to the moon and minmus in my current career save after only a week or 2 (The entire stack weighed about 300 tons; what made it to the mun was around 30-60 tons). And i frequently exceed the megaton range now ; fuel is silly cheap compared to engines/crew and reuse means essentially i'm only paying fuel costs.

That being said i find your arguement in favor of the Panther interesting; pushing whiplashes to Mach 1 wastes a lot of fuel before hitting the efficiency curve where they're actually doing work. Panthers would start out decent and only get better before flaming out; i may be running some tests fairly soon because of you xD.

Unfortunately, I don't really think there's a good way to balance the RAPIER for use in career.

If you're at the end of the tech tree (or close to it), then you've already spent millions to upgrade the science building to maximum, and various other buildings probably to at least level 2. That means that you've managed to earn all that money without using reusable SSTOs. Once you do get the tech for SSTOs what do you really need to make money for? Other than for the fun/challenge, there's really no need (no different than reusable SSTOs in Science/Sandbox modes)

[Incarnation of Chaos]

14 hours ago, Empiro said:

Unfortunately, I don't really think there's a good way to balance the RAPIER for use in career.

If you're at the end of the tech tree (or close to it), then you've already spent millions to upgrade the science building to maximum, and various other buildings probably to at least level 2. That means that you've managed to earn all that money without using reusable SSTOs. Once you do get the tech for SSTOs what do you really need to make money for? Other than for the fun/challenge, there's really no need (no different than reusable SSTOs in Science/Sandbox modes)

That's kind of my point; you're getting the rapier when it reaches the point of being least useful. But the engine itself is so powerful it can't really move.