How much more flying time does SSTO consume?

[Jestersage]

While trying to make my lunex clone, I can't help but to think that, if I am going to do it purely in concept, I may use SSTO instead, if I am not pressed for flying time.

Is that true in general, that SSTO require more flying time to create a stable orbit that is smaller, compare to rockets that can generate a large orbit in a shorter amount of time?

Edited December 1, 2016 by Jestersage

[Jefzor]

Yes, SSTO's take more playing time to fly into orbit. 

[Thor Wotansen]

Honestly, I don't think the difference is that big.  I have an SSTO that can loft 50t to LKO in around 12 minutes of game time.  Real time is longer due to part count and my low end laptop.

[Jestersage]

Kind of thinking like that too. I mean, my Lunex clone deliver 10 Kerbal, a rover, and a full science package (no lab) to mun/minmus direct ascent; I am sure your SSTO could do the same (and more, I think)

The only reason I think Lunex / Plane-on-a-stick is better is if I care about every seconds, and want to get into position ASAP

Edited December 2, 2016 by Jestersage

[fourfa]

If you fly a standard rocket on the very most efficient path (long time in atmo, circularize 180 degrees from KSC for ~40m/s) it takes forever.  If you spend some extra some dV going to space faster and sooner with a much heavier circularization burn, it can be very quick.

If you fly a SSTO on the very most efficient path (long time in atmo, circularize 180 (ish) degrees from KSC for ~40m/s) it takes forever.  If you spend some extra some dV going to space faster and sooner with a much heavier circularization burn, it can be very quick.

Edited December 2, 2016 by fourfa

[Frank_G]

An efficient SSTO with low TWR takes three to four times the time to orbit - or even more. If it is overpowered (like a rocket with large wings), you can almost achieve the same time like when launching a rocket. It wont be efficient in any ways, considering payload fraction and fuel usage, or in other words, totally pointless.

If you want something up there fast use a rocket, if you want something up there with best fuel efficiency and a payload fraction between 30 and 50%, then use an SSTO.

[fourfa]

On 12/12/2016 at 5:00 AM, Frank_G said:

An efficient SSTO with low TWR takes three to four times the time to orbit - or even more. If it is overpowered (like a rocket with large wings), you can almost achieve the same time like when launching a rocket. It wont be efficient in any ways, considering payload fraction and fuel usage, or in other words, totally pointless.

Yeah, that doesn't match my experience at all.  I have a recoverable 50T vertical SSTO rocket and a 50T Mk3 cargo SSTO spaceplane - the plane burns about 1/8th the fuel for the same payload in the same orbit.  And this is a 10-rapier overpowered missile of a plane that gets to orbit in a hurry, and will never win an efficiency challenge.  But it beats the heck out of the rocket for efficiency, both in fuel and recovery percentage

Besides which, the plane is more fun to design, build, test, perfect, and operate - for me, anyway, at this stage in my game experience.  I did previously concern myself more with accomplishments per hour.  Now I'm more and more interested in creatively technical ways to do the same things more elegantly.

TL;DR: "Pointless" is in the eye of the beholder

[Sharpy]

Primarily, apples to apples.

Time according to in-game clock, to reach orbit in SSTO vs a rocket on optimal ascent trajectory is quite comparable, unless your SSTO has poor TWR or poor lift and say, takes forever to climb to 10km or you struggle to breach sound barrier and have the engines kick into ramjet mode.

Time according to your wall clock is way in favor of rockets. In SSTO you must actively fly the airplane almost all the time, and almost all the time at 1x speed. In rocket, you warp through almost half of the ascent time.

And if your SSTO doesn't have superior TWR, you're in for a LOOOONG flight. A small drone using a single LV-N and a single Whiplash can reach the orbit perfectly well, and with fuel to spare, in some... 30 minutes?

And never forget the time it takes to land the SSTO.

Edited December 14, 2016 by Sharpy

[Frank_G]

Yes. My most efficient SSTO had a TWR Below 0.4 and took almost 30 minutes to orbit and another 20 to land, but it lifted 40 tons to orbit on 6 R.A.P.I.E.R engines. Very cost efficient but it takes time and skill to get it through the soundbarrier.

Since the new aero-model, it needs a bit of tweaking, but it (Morray Delta VI) can be downloaded on my craftfile thread in its original pre 1.2 form, if someone wants to take a look.