Are SSTO's worth it?

[Ozymandias_the_Goat]

15 minutes ago, Pthigrivi said:

True, the only real advantage is because Im not trying to precisely land on the runway most of the journey down can be done on physics warp, aside from a dicey stretch around max-q. Probably a well-designed spaceplane could time-warp close enough to only pilot the final approach too though? The other half is just how much faster it is to launch an SSTO rocket over an airbreather. 

It’s not an obscure truth that a rocket SSTO is simply more practical, faster, and easier to use than a plane. Rockets are practical, but planes are fun.

[Pthigrivi]

12 minutes ago, Ozymandias_the_Goat said:

It’s not an obscure truth that a rocket SSTO is simply more practical, faster, and easier to use than a plane. Rockets are practical, but planes are fun.

Yeah I love the challenge of a good spaceplane. I wanted to use one as my main launch platform but after putting up 50 or so modules Im glad for ease of use. 

[Sharpy]

1 hour ago, Pthigrivi said:

True, the only real advantage is because Im not trying to precisely land on the runway most of the journey down can be done on physics warp, aside from a dicey stretch around max-q. Probably a well-designed spaceplane could time-warp close enough to only pilot the final approach too though? The other half is just how much faster it is to launch an SSTO rocket over an airbreather. 

It also depends how precisely you can target your reentry point. Circling half of Kerbin in orbit, at 2200m/s takes over 20 minutes. So, if you fly from the opposite side of Kerbin at 440m/s (a reasonable cruising speed that won't leave you without fuel halfway through), that's 50 minutes. 12 minutes at 4x phys-warp, if your computer is fast enough and the plane is simple enough to get the full 4x boost. You'll usually reenter way closer, still, with planes complex enough (part count), with being short on fuel and having to fly 'economy speed', with exitting phys-warp for adjusting the course (doing it under 4x is just asking to flip and crash), you can estimate 5-10 minutes just for the return flight. That is without time taken for safe approach, or airbraking into the atmosphere.

[Hodo]

There is always a second option, which I cant believe I didnt think of till last night.

A tail sitting rocket primary, jet secondary engine system.   

 

You use the rockets for launch and re-entry but on finale landing and adjustments you use the jets.   This will give you a bit more control and les fuel concerns.  Downside is you are pretty much haulling dead weight into space.

[Cavscout74]

On 11/20/2018 at 4:45 PM, Sharpy said:

It also depends how precisely you can target your reentry point. Circling half of Kerbin in orbit, at 2200m/s takes over 20 minutes. So, if you fly from the opposite side of Kerbin at 440m/s (a reasonable cruising speed that won't leave you without fuel halfway through), that's 50 minutes. 12 minutes at 4x phys-warp,

Most of the spaceplanes I use have a sweet spot for cruising at 20-25km, ~1800-2000 m/s for the times I undershoot reentry.  Generally, I can set the Rapiers to 40-50% power in airbreathing mode, set the nose roughly on the horizon, and leave it alone till I get close enough to start my landing descent.   It's usually stable enough for physics warp, at least x2 or 3, maybe 4 if I'm feeling lucky.  I've actually started aiming for a slight undershoot just because that high altitude cruise is easier than overshooting & turning back to KSC. 

But even that is a longer process than a vertical launch & landing rocket.   I enjoy my spaceplanes, but they are time consuming to use.

[FlyingPete]

I've never had much patience for spaceplanes. They're tricky to build, hard to fly, time-consuming to launch and land, and just not very enjoyable. They only really make sense for crew shuttles to LKO. Once the crew are there, they transfer to the real spacecraft to get where they're going.

Reusable spacecraft are another matter. Vertical SSTO shuttles cost only fuel and maybe some heat shield material, and I've previously set up a completely sustainable transit system between Kerbin and Minmus. Single-stage rocket goes between ground and the LKO station, nuclear bus gets to Minmus station, and reusable landers go from there to the surface. The bus and landers refuel at Minmus station using Minmal ore-based fuel.

Spaceplanes might make more sense at Laythe, where the lesser gravity would increase the useful payload.

[Freds]

SSTO are Cool, but, i think its almost useless.
I use SSTO only for LKO.
Lately i equiped my LKO SSTO with droptanks to increase range as a insurance againt piloting errors. (They still are SSTO if i remove the tanks) 

I use Space Planes (with drop tanks, they cant archive orbit without this) as crew and cargo transport for my HKO Space Station (700Km orbit).

Specially designed vehicles for all other things.

As a rule, all my planes designed for Kerbin operations has parachutes on the tail - it makes really easy to stop before the runway ends.

I only use SSTO, with VTOL and Mining  for Laythe.

For EVE, planet that all my missions are non-return drone missions, a glider is nice to bring rover to a nice landing  spot (its better than a ballistic landing, specially due to montains). Parachutes on front and back ensure a nice and safe landing.

[Hodo]

On 11/16/2018 at 2:03 AM, Sharpy said:

SSTO spaceplanes are not money-savers.

They are money-savers per Kerbin hour, but with the time compression at hand's reach that means very little. They are definitely not money-savers per player's hour.

Say, your average contract done the 'disposable' way will take, say, an hour to complete, and yield 70% of the offered profit. It will also take about 5 Kerbin hours.

The same contract done SSTO way will yield 98% profit (providing you don't crash), take maybe 6 Kerbin hours (return flight home!), but in real time it will take 2-4 hours of your attention. You could do 2-4 contracts "the disposable way" in that time.

That being said, SSTO launchers - rockets - are a money-saver. Launch goes the same, landing them takes maybe 5 minutes, and you get ~90% ROI (you won't land them at KSC, but you'll get >70% recovery value).

Make no mistake, FMRS and similar stage-recovery techniques are not money savers for the same reason SSTO spaceplanes aren't. In the time it takes you to safely land and recover all the boosters you could've flown half of another contract.

 

BUT SSTO spaceplanes are fun and challenging! Do you need more reason than that to build them?

I dont really agree with this.  But it does ultimately come down to play style. 

I can say that a few years ago when there was a challenge in the challenge section of the forums about building a space station using a reusable launch system that you could not despawn had to stay in the game and you had to find a way to refuel it, and load the new cargo module on it and get it ready for launch... I found that my SSTO program at that time was MORE than up for the challenge.  And I in a matter of 3-4 real life hours put over 200 tons in orbit and assembled a space station that I actually continued to use for my space program till the update killed my save. 

 

 

[Wilds]

I have gotten into long range SSTO's on stock 1.4.5/1.5.1. So far, I give the plane enough fuel to get to Minmus by emptying most of the tanks in SPH. Landing on Minmus, I open the cargo bay and start mining. My smaller SSTO gets around 8000 dV after escaping the Kerbin system. It cannot land and takeoff from Tylo, Moho, and Eve.

My larger SSTO has a similar design but holds way more oxidizer, and has 2.5x more engines.It does lose over 1000 dV though. It can land and takeoff from Tylo which was a big achievement for me... I have yet to land on Tylo without using quicksave/load as it takes a few attempts to get right. I really want to make a stock Eve SSTO, but that is a long ways off, if possible (without looking like a monstrosity). I will have to radically change the design for EVE.  The larger SSTO can at least fly around EVE for around 5 minutes in between mining.

I spend a long time making sure CoL and CoM are nice and center, no matter what fuel level. Landing at Duna does require some time as you cannot land at a high speed. Since these planes carry so much fuel, I loathe landing at Duna with a lot of fuel.

The small design uses 2 Rapiers and 2 NERVs, while the larger design uses 4 Rapiers and 6 NERVs. I use the Puff mono-propellant engine for VTOL. Having an Engineer is essential for mining quickly. 

 

I used to thing SSTO's were not capable of long range space exploration, but I am glad I thought wrong. I originally wanted an SSTO to land on Minmus or the Mun and return without refuel. Now I have no idea where the limit is. I love seeing other people's SSTO's as I am always impressed with their performance characteristics. I do want to keep my builds stock for now, but I am getting ready to move on.

I think the next major challenge is making a good SSTO for Real Scale Solar System. That will require a big redesign.

 

[Zosma Procyon]

In the real world they're much better than the pathetic little capsules we're degenerating to, but in the world of KSP they require more effort than I want to use for my fun time.

[Eriksonn]

I usually dont make many spaceplanes but every once in a while i make a mk2 plane for taking kerbals to/from a space station or something similar.

Once I made a tiny ssto that could get to minmus and back. I was really proud of that one.

[Pecan]

19 hours ago, Zosma Procyon said:

In the real world they're much better than the pathetic little capsules we're degenerating to, but in the world of KSP they require more effort than I want to use for my fun time.

You base this statement on which real-world SSTOs, exactly?