Skiff vs. Wolfhound?

[GunnDawg]

Just messing around with some rocket ideas and the new engines in the DLC, and I've been wondering when you would use the Skiff vs. using the Wolfhound. So far I've used the Wolfhound for both my 2nd, and 3rd stage engines, with no issues, but would the Skiff work better? I'm bad at numbers so I was hoping someone on here could tell me when to use the skiff, as opposed to using the wolfhound for all my vac. space flight.

[MR L A]

Well I have a craft that is capable of taking 3 Kerbals to the space station at 200KM (and a bit beyond) that uses a Skiff as a first stage engine... its pretty efficient and fun tbh, does require two srbs though... but still fun. I'm in Career mode so I also factor in cost and the Wolfhound certainly isn't cheap.

If you want some help with the numbers, download Kerbal Engineer... does all the math/s for you and you'll quickly pick up what the output numbers mean

But as for your question, it TOTALLY depends on the situation  wolfhound for vac flight is generally a good idea though 
 

[Zeiss Ikon]

Generally speaking, a vacuum engine (like the Wolfhound) suffers significant loss of Isp at sea level.  I haven't used either the Skiff or Wolfhound yet (still playing with launchers that were designed in 1.3.0), but I'd generally expect the Wolfhound to be the better choice for transfer orbits, where the whole burn is in vacuum, while the Skiff would be a better choice for a launch, where you start the burn in dense atmosphere.  I'll have to look at the Skiff, though, to see if it might replace my current favorite first stage motor, the Twin Boar.  Maybe in pairs on an engine plate, to get the necessary thrust...

[Snark]

3 hours ago, GunnDawg said:

I've been wondering when you would use the Skiff vs. using the Wolfhound.

Wolfhound:  with that amazing Isp, it's the hands-down winner for anything reasonably large, for any stage that activates at 10 km or higher.  But utterly unsuited for lifting off the launchpad (abysmal atmospheric Isp).

Skiff:  Makes a decent mid-sized engine for lifting off the launchpad:  pretty good atmospheric Isp, pretty good vacuum Isp (better than Skipper / Swivel / Reliant), more thrust and less mass than a Swivel or Reliant.  Also makes a pretty good sustainer engine during ascent.  In vacuum (e.g. orbital operations):  It's better suited than the Wolfhound for smaller ships where the difference between the Skiff's 1 ton and the Wolfhound's 2.5 tons is significant.  (High Isp or not, for a small enough ship, the Wolfhound's extra 1.5 tons of dead weight will end up hurting the economics more than its Isp helps).

 

[KerikBalm]

IMO, the wolfhound is OP'd. All you need are jets or SRBs to get you above about 8km (go higher with jets though), and then that engine is all you'll ever want/need until you get into really extreme dV requirements, at which point you're only looking at LV-Ns as competition