Part Rebalance

[KerikBalm]

Issue: Some parts are clearly better than other parts.

Additional issue: Small parts being superior to large parts leads to very high part counts.

Proposed solution: make the large (ie, rockomax, I'm not really talking about the new extra large parts) parts better, and nerf the 48-7s.

Suggestion #1: The Skipper has a TWR inbetween the LV-T30 and LV-T45, but its ISP is far less - Give it the same ISP as those two (320-370)

Suggestion #2: The 48-7s has a superior TWR to the Mainsail, and superior ISP -> swap the ISP of the mainsail and the 48-7s (this should also help the disparity between the mainsail and the new lquid fuel boosters and extra large engines)

Suggestion #3: The poodle has a worse TWR than the lv-909, and a worse non-vacuum ISP -> Decrease its weight to that it has a comparable TWR.

Mass 2.5-> 2.25

And slightly unrelated:

The Aerospike... I'm finding it not very useful. I don't have the numbers to say some other part is just plain better, but it seems to me that its TWR is too low.

The advantage is its high atmospheric ISP, implying its intended use is low in atmospheres -> ie Eve, Kerbin, or Laythe (duna's is too small to really matter that much, and you can't land on Jool...). And obviously on thoe bodies, the descent will be done with 'chutes, so that leaves using them during the liftoff ... ie as boosters, which need a high TWR, which they don't have.

I did an eve ascent with them, I'm not sure I gained any dV using them given my TWR was too low. Going from 388 ISP for most of the ascent to 320 may be offset by a higher TWR resulting in less dV lost to gravity drag.

Suggestion-> increase thrust to 200 kN

[r4pt0r]

http://forum.kerbalspaceprogram.com/threads/75272

[Jouni]

The Aerospike... I'm finding it not very useful. I don't have the numbers to say some other part is just plain better, but it seems to me that its TWR is too low.

The advantage is its high atmospheric ISP, implying its intended use is low in atmospheres -> ie Eve, Kerbin, or Laythe (duna's is too small to really matter that much, and you can't land on Jool...). And obviously on thoe bodies, the descent will be done with 'chutes, so that leaves using them during the liftoff ... ie as boosters, which need a high TWR, which they don't have.

The Aerospike is a good engine with no obvious uses (except Eve landings). It looks like a first stage engine, but it doesn't work too well in that role, as it doesn't have enough thrust per surface area. It's much better as a vacuum engine, because it has the same Isp and better TWR than the LV-909, while providing more thrust for its size than any other engine of comparable efficiency. It's also quite short, meaning that it often fits well in landers and spaceplanes.

[Rusty6899]

The aerospike is useful for asparagus staged rockets going to Mun or Minmus, if you want to keep the weight low. It may be that with the newest engines you can achieve the same results more cheaply. It's pretty obvious from looking at it that it's strength should be ascending from atmospheric bodies, but I think that if its thrust were improved much, then it would become OP.

[KerikBalm]

maybe decrease its ISP to be 370, so its equal with the LV-T30/45 in a vacuum, but better in the atmosphere - give it the same TWR of the LV-T45.

Then remove the alternator.

That way you trade vectoring, electric charge, and stacking ability for a better atmospheric ISP.

At 390 ISP, it is competing with engines meant for use in vacuums: the LV-909 and Poodle. Right now I use it to replace those - its shorter than the poodle, with nearly as much thrust, and a better TWR. I've been using it as a lander engine for Mun/moho/Duna - none of which use its good atmospheric performance.

I was able to do an eve ascent with it, but I think 48-7s clusters are still more efficient, The TWR of my aspargus stages aerospikes and FL-T800s was pretty bad. Using smaller tanks results in a very high engine mass:fuel mass ratio. I'm pretty sure the 48-7s is better -at least for the lower stages, and the new extra large parts with an atmo ISP of 360 and much better TWR also look like they will make the aerospike not favorable for Eve landings.

So, nerf 48-7s, buff aerospike, buff all large size engines.

[Jouni]

I was able to do an eve ascent with it, but I think 48-7s clusters are still more efficient, The TWR of my aspargus stages aerospikes and FL-T800s was pretty bad. Using smaller tanks results in a very high engine mass:fuel mass ratio. I'm pretty sure the 48-7s is better -at least for the lower stages, and the new extra large parts with an atmo ISP of 360 and much better TWR also look like they will make the aerospike not favorable for Eve landings.

So, nerf 48-7s, buff aerospike, buff all large size engines.

The 48-7S is a good engine for small Eve landers, if you just want to land on Eve in a command seat without any significant payload. In bigger, more reasonable landers, the number of engines and attachment parts just gets out of hand when using the 48-7S.

The new big engines may be good as the first stages of an Eve lander. Their Isp is low (280 or 320 seconds), but raw power and low part count may be more important than efficiency in big landers. Still, you are going to need something else for the middle stages (something like 15-30 km). The lander has probably already lost 90% of its mass by the time it reaches 15 km, and the big engines need a lot of fuel to be useful.