Convert real life engine thrust to KSP?

[xtoro]

What's the guideline for this? I know everything in KSP is scaled down, but what about thrust? If a certain engine in real life produces X thrust, would it produce the same in the game or is there some common conversion done here? Or, is it just do what you want as long as it's not too OP?

[kunok]

I'm looking for that too, there it's a guide of how convert real parameters to KSP scale? I can't find none

[DennyTX]

well, my way:

1. somewhere i read about magic scale coeff in KSP - 0.64 (well, all my RL models like APOLLO or GEMINI scaled down using 0.64)

2. also, upper border of Kerbin's atmosphere are about 2.2 low than Earth one but same G.

3. so, i scaled trust of RL engines KSP_htrust=RL_Thrust/0.64/2.2

[Nansuchao]

With Realism Overhaul you have real values for engines.

[xtoro]

well, my way:

1. somewhere i read about magic scale coeff in KSP - 0.64 (well, all my RL models like APOLLO or GEMINI scaled down using 0.64)

2. also, upper border of Kerbin's atmosphere are about 2.2 low than Earth one but same G.

3. so, i scaled trust of RL engines KSP_htrust=RL_Thrust/0.64/2.2

Thanks! I'll try fiddling with those numbers.

With Realism Overhaul you have real values for engines.

That doesn't help with stock KSP now does it?

[Phineas Freak]

A quick way to "rescale" a real life engine for the stock KSP is to first multiply the engine mass by 0.262 (equal to 0.64 ^ 3) to get a "rescaled" mass and then use the TWR value of the real engine to find out the thrust for the stock KSP. The last step can be accomplished by using the TWR equation but reversed:

EngineThrustRescaled = EngineMassRescaled * (EngineTWRReal / 100)

I used this method to create a lot of real life launch vehicles before starting tinkering with RSS. I was impressed to find out that the Atlas V and Delta IV replicas i made had the same payload capability as the real ones (of course on rescaled payload masses).

The only problem is that i have not found a way to "rescale" the Isp values yet. Usually i play around with the ASL and VAC values for the best possible balance .

[xtoro]

TWR!! That's genius! Then the kN's don't really matter as long as the twr is right. THANK YOU so much! As for the isp, that's something I'll have to play around with I guess. Now if I can only get my model to come out properly and with a texture.... The old modeling guides aren't helping much with using Blender...

[Streetwind]

Stock KSP has extremely low TWR on all of its engines. If you use RL engine TWRs, your additions will not fit with stock at all.

This is a fine example of "realism for the sake of realism" and why it should be avoided. Stock KSP is not realistic; you're much better off statting up your engine with a useful and balanced niche than to blindly convert RL stats.

Realism has its place, but by definition it requires you to depart from stock for it to make sense and feel consistent. That's why the Realism Overhaul crew is putting in such a huge amount of work.

[xtoro]

Don't get me wrong, not looking for realism, just asking how people balance engine thrust for engines based on real life engines...

Edited July 16, 2015 by xtoro