[1.11+] Specify EVA RCS parameters in the Jetpack part cfg, not kerbalEVA

[PocketBrotector]

1.11 introduces the EVA jetpack as a discrete, removable/swappable part, which is an improvement in customizability over the old system where it was built directly into each kerbal's EVA suit. However, most of the jetpack's characteristics (linear and rotational thruster power, propellant consumption rate, etc.) is still specified in the kerbalEVA config rather than the jetpack config. It would be good if these were part of the jetpack rather than part of the kerbal, as this would open up the possibility of customized, specialized jetpacks in mods or stock:

• Different jetpacks could have stronger or weaker thrusters. Want to fly on Tylo? Or maybe you want more realistic thrusters that are only good for maneuvering in microgravity? 
• Different jetpacks could have different effective specific impulses, and/or different propellant capacities. 
• We could specify that a jetpack uses a fuel other than generic "EVA Propellant," e.g. Nitrogen or another realistic cold-gas resource from CRP.

All of these factors together, along with total jetpack mass, could provide multiple EVA propulsion systems with different capabilities. This in turn can be used to provide more interesting choices when planning mission architecture, etc. 

[Starhelperdude]

amazing Idea!

solid rocket jetpack with super high twr would allow suicide burns and stunst xD

also ion jetpack and stuff!

[jimmymcgoochie]

I agree that the EVA jet pack stats should be put into that part’s config, but I don’t see the need for any additional variants of the EVA pack- the only place where it would actually matter is Tylo as anything larger (Laythe, Kerbin, Eve) has an atmosphere that makes RCS essentially useless, and Tylo is too niche to deserve a special version just for it.

Re. the propellant used by the EVA pack- Kerbalism swaps that to monopropellant (which just means you need to bring some along but makes no difference to performance) and RP-1 to Nitrogen (which is the worst RCS propellant for ISP by some margin), so I see no reason why you can’t just write a patch to swap the propellant to anything you feel like; having effectively infinite propellant by just popping back into a pod for a refill is a bit silly though.

[PocketBrotector]

1 hour ago, jimmymcgoochie said:

Re. the propellant used by the EVA pack- Kerbalism swaps that to monopropellant (which just means you need to bring some along but makes no difference to performance) and RP-1 to Nitrogen (which is the worst RCS propellant for ISP by some margin), so I see no reason why you can’t just write a patch to swap the propellant to anything you feel like; having effectively infinite propellant by just popping back into a pod for a refill is a bit silly though.

Looking at how Kerbalism accomplishes this, I see that the propellant type is defined (and modified) in the kerbalEVA config. So like the other parameters, you can override it but it will affect every kerbal in the universe - no variants allowed.

You’re probably right that jetpack variants would have a niche purpose, but that’s exactly why the parameters should be exposed. Modders who are interested would be able to access them without unwanted effects to “regular” jet packs.

@Starhelperdude has some nice ideas above. I’m also interested in a semi-realistic version that’s suitable for spacewalks without being so super-powered that it can also be used for e.g. Minmus landing/ascent. I imagine there’s also the possibility of an atmo-optimized version, or more fancifully, a pack that has air intakes and fans or true jet engines for atmospheric flight.