Do you SSTO anymore?

[KerikBalm]

So, in adpating to the recent changes, I've given up trying to SSTO everything.

The recent changes:

* Expanded physics distance

* Halved jet engine thrust

When trying to SSTO everything, I'd use big launchers to minimize the number of launches and re-entries I'd have to do...

As a result, my launch masses are often around 400 tons (and when actually near the payload mass limit, I'm getting >35% payload fractions)

The recent reduction to jet thrust makes the liftoff quite awkward. I also find that having to set a positive pitch angle with lower rear landing gear than front landing gear increases the risk of long payloads striking the ground.

The short burn time of the kickback SRBs + the increased physics draw distance means I can jettison them after burnout, and have them safely land on the runway

- full recovery cost for the decoupler parachute, and SRB itself - the only cost is the solid fuel, which amounts to 84 credits per kickback.

As a result, I'm now doing a lot of designs which stage while still over the runway.

8 kickback SRBs to help lift the nose, and then accelerate and climb above the runway really helps to get a 400 ton behemoth into the air.

Its equivalent to the thrust of >12 extra rapiers, or 10 extra turboramjets, and extra 3.26 m/s/s of acceleration (for a 400 ton spaceplane) on takeoff

All for the low low cost of 84*8 = 672 credits.

Considering the SSTO normally recovers with remaining fuel for >350k, and that fuel costs are about 15k for large payloads, its not much...

It only adds ~4% to the cost of fuel.

Is anyone else finding ways to make use of the longer draw distances to recover booster stages?

I can't manage anything like what spaceX wants to do due to physics limitations... but I find the short burntime of kickbacks to be perfect for 1st stage recovery.

Im also starting to try it out with vertically launched rockets, and I want to try out some RT-10s instead of RT-5s. Anyone tried this?

I'm worried their burn time is too long and they'll still be under parachutes when they get 22.5 km away, and they'll thus despawn.

I'd still like to have another stage, that I decouple on a suborbital trajectory, get the payload to orbit, and then switch back to the suborbital stage... but it will land so far away, recovery losses likely won't make up for the reduced fuel costs

(What I wouldn't give to be able to decouple a rocket from a plane at 30km going ~1,300 m/s surface velocity, and then be able to turn the plane around and land... or to make a 2nd space center to the east where craft could be landed for a higher recovery value)

[Red Iron Crown]

Funny, I use SSTO planes *more* since the changes. The pre-1.0 turbojets were so stupidly OP that it felt like cheating to use them for any serious mission. Now they feel like a more palatable option plus the new aero is interesting, so I use them for crew transfer and small payloads. I still do big payloads with multistage rockets, the part count for big SSTO planes kills them for me.

Disclaimer: I'm mostly a sandbox player, the funds recovery is meaningless to me. I recover nothing but pods and spaceplanes.

[Lyneira]

Try Flight Manager for Reusable Stages, it lets you do stuff like fly a first stage rocket or plane back to base after detaching in the atmosphere with some save file snapshotting magic.

In my latest career game where I added an MKS/OKS module to my space station, I try to launch everything I can with SSTOs, my largest one can get about 46 tons of cargo in a Mk3 cargo bay to orbit but that plane gets a bit close to the limit I'm comfortable with for part count (8 rapiers) and also wing usage. (big-s delta wing clipped partially into the big airliner main wing)

Edited August 11, 2015 by Lyneira

[Pecan]

I SSTO nearly all the time. Hardly ever use spaceplanes or airbreathing engines though. Then again, my maximum payload is only around 40t - anything larger gets assembled in orbit.

ETA: come to think of it, I hardly ever use SRBs either. LFO is cheap.

[Sharpy]

I SSTO all the time. Credit goes to Warzouz, for his Cygnus family.

I don't SSTO only with ridiculously oversized loads where Asparagus becomes a necessity - or ridiculously undersized ones, which I just stick on top of a single Kickback. And if my payload is mostly fuel tanks, I make it non-recoverable SSTO by sticking some engines on these tanks and dumping them near the destination.

Now, for SSTO spaceplanes...

Edited August 11, 2015 by Sharpy

[capi3101]

I SSTO as much as possible, going both ways - rockets or planes - as I feel appropriate. Admittedly these days I'm using FAR. I've also stuck to 1.0.2; from the way things sound from all y'all's posts all over these boards, it sound like not upgrading to 1.0.4 was a sound decision (though I've considered going to 1.0.4 and installing DRE - which apparently is kinder than stock at this point as far as heating goes).

[Val]

...

The short burn time of the kickback SRBs + the increased physics draw distance means I can jettison them after burnout, and have them safely land on the runway

- full recovery cost for the decoupler parachute, and SRB itself - the only cost is the solid fuel, which amounts to 84 credits per kickback.

As a result, I'm now doing a lot of designs which stage while still over the runway.

8 kickback SRBs to help lift the nose, and then accelerate and climb above the runway really helps to get a 400 ton behemoth into the air.

Its equivalent to the thrust of >12 extra rapiers, or 10 extra turboramjets, and extra 3.26 m/s/s of acceleration (for a 400 ton spaceplane) on takeoff

All for the low low cost of 84*8 = 672 credits.

Considering the SSTO normally recovers with remaining fuel for >350k, and that fuel costs are about 15k for large payloads, its not much...

It's not really an SSTO if you're dropping boosters, is it?

But to answer your question, Yes, I do almost exclusively spaceplanes now (RIC got me hooked), most of them are Single Stage, but not all.

I really like the Aerodynamics in 1.0.4 and spend almost all of my KSP time, building highly optimized spaceplanes. Sometimes for challenges and sometimes just to see if I can.

[Grumman]

I'm doing a nothing but spaceplanes run. I cheated myself enough science and funds to unlock the spaceplane parts and went from there.

I perform suborbital flights by taking off from the runway, pulling straight up and then coasting out of Kerbin's atmosphere when the engines cut out.

I've currently got a two-seater SSTO and I am working on a 6-seater.

[Red Iron Crown]

Yes, I do almost exclusively spaceplanes now (RIC got me hooked)

That's a first, I consider myself more of a rocket guy.

[xtoro]

I started doing SSTO after 1.0 when it got interesting. I agree with RIC that it was too OP before. You should not be able to establish a 150km AP from within the atmo using only jets... That made using rockets almost pointless for satellite launches, and there were way more SSTO flyers and builders before 1.0 because it was so easy. SSTO that could tour the whole system were a joke.

[Mikki]

I do SSTO all the way . As aviaton fan,

SSTO is MANDATORY in KSP!

Even unkerbaled (maybe better sometimes,... this drone here is too stupid to realize that there is no flat landingsstrip underneath...)

Happy grounding!

[Wjolcz]

I just SSTO'd today. Also, more bragging:

Javascript is disabled. View full album

[GoSlash27]

Absolutely! I use staged rockets for assemblies and SSTO spaceplanes for crew and supplies.

Best,

-Slashy

[Slam_Jones]

It's become much more difficult, certainly, but I still enjoy the satisfaction of a successful SSTO trip (especially if it goes further than just LKO)

[Pecan]

It's not really an SSTO if you're dropping boosters, is it?

Yep, "Single Stage", "To Orbit" - seems simple enough to understand, but what can you do?

...a successful SSTO trip (especially if it goes further than just LKO)

*Sigh*

Hehe, which is also fun, because I recently posted my 'SSTO to Eeloo' which is an ion probe that jettisons it's Single Stage launch-rocket once it's got To Orbit. Well, if it's SSTO there's no rules about what happens afterwards, are there?

[panzer1b]

That's a first, I consider myself more of a rocket guy.

really, what about me......

The only 2 reasons i even touch rockets at all are for capital ships (as epic as my SSTO capable 200t normandy replica was, 1.0 killed it so no more SSTO capital ships), and for launching fighters that are space only (its hard enough to get a carrier in orbit, need to bring the fighters/ammo up separate).

Aside from this, virtually everything i make including low altitude only jet planes are SSTOs or SSTLs (single stage to laythe), and atmosphere only planes are essentially SSTOs with rapier/nuke swapped for a basic or turbojet and a few tweaks to fuel loads, and wing locations.

Really the only thing limiting my enjoyment of SSTOs is teh fact that the nukes are so bloody heavy and awkward to use. What id do for a shorter (at least half as short) nuke that maybee has halfish weight and halfish thrust of the current, thatd actually be useable on sub 15t SSTOs that are for now limited to either ion (cant stand the bad TWR and part counts), or pure rapier (terrible dV).

Never liked large aircraft though, part count and they are not really fun to fly for me (everything i send to space, even my capital ships have enough reaction wheels for good maneverability).

All in all, i like the new challenge, but i am sad that for now my legit aesthetics SSTOs cant get to laythe, land, and return to kerbin. Ofc ive managed by abusing bugs and exploits (K-Drives, clipping ions and ion fuel into service bays, editing probe cores to have inf electrcic charge), but its a challenge to make a ssto make it to laythe and back without sacrificing appearance (anyone can get a stack of fuel tanks with a cockpit in front, rapier+nuke in back, and wings to sides to laythe and back).

[KerikBalm]

It's not really an SSTO if you're dropping boosters, is it?

Thats the point... before 1.04, I was using single stage to orbit designs.

Post 1.04, I've started adding RATO assist to my spaceplanes, making them no longer SSTOs, despite 100% recovery.

I'll also add kickback boosters for rockets now, because they can be recovered easily

[xtoro]

Yep, "Single Stage", "To Orbit" - seems simple enough to understand, but what can you do?

*Sigh*

Hehe, which is also fun, because I recently posted my 'SSTO to Eeloo' which is an ion probe that jettisons it's Single Stage launch-rocket once it's got To Orbit. Well, if it's SSTO there's no rules about what happens afterwards, are there?

Buuuuut, technically, while using only one stage to get to orbit, you're still launching two stages to orbit, even though you use the 2nd stage once IN orbit... Definition not too clear I guess.

[Red Iron Crown]

(anyone can get a stack of fuel tanks with a cockpit in front, rapier+nuke in back, and wings to sides to laythe and back).

Ouch, and here I thought I had accomplished something somewhat difficult. Are you ever going to update the challenge you started about it?

[Pecan]

as epic as my SSTO capable 200t normandy replica was, 1.0 killed it so no more SSTO capital ships

What's wrong that you can't SSTO 200t? Admittedly, the biggest I've bothered to do is 130t, but it's all doable - ask any Whackjob.

Buuuuut, technically, while using only one stage to get to orbit, you're still launching two stages to orbit, even though you use the 2nd stage once IN orbit... Definition not too clear I guess.

I'm quite happy with the wikipedia definition "A single-stage-to-orbit (or SSTO) vehicle reaches orbit from the surface of a body without jettisoning hardware, expending only propellants and fluids. The term usually, but not exclusively, refers to reusable vehicles" (https://en.wikipedia.org/wiki/Single-stage-to-orbit). It seems pretty clear to me - if it only uses a Single Stage to get To Orbit, it's a SSTO. Doesn't even have to come back or be able to do anything once it gets there (although there's no real point if it isn't reusable). Doesn't matter if, having got To Orbit with a Single Stage, it separates, refuels or turns pink and plays Ode To Joy. It's a SSTO. My whole point is that that design is definitely NOT a Single Stage To Eeloo, which is why I called it SSTO to Eeloo. That's why misusing the term "SSTO" all the time is annoying. panzer1b has it right with SSTL.

[Val]

Buuuuut, technically, while using only one stage to get to orbit, you're still launching two stages to orbit, even though you use the 2nd stage once IN orbit... Definition not too clear I guess.

The definition is clear. Single Stage To Orbit means that you only use one stage to get to orbit. It does not mean you can't bring more stages, to go further.

Edit: Ninja'ed by Pecan

Edited August 11, 2015 by Val
Ninja

[Fearless Son]

Actually, I had given up SSTOs prior to 1.0, then picked them up again after. Mostly because I refused to airhog in the old version, and it became clear to me that I could not build the kind of SSTOs I wanted to with the old aerodynamics model. The new model makes things... well, not really easier or harder, but different. A new set of rules to learn. I enjoy that you no longer need an absurd amount of intakes, I like that overloading intakes provides no additional benefit, I like that lift has a better relationship with thrust, I like that drag is now a prime consideration which influences design, etc.

[Pecan]

More seriously - because I don't really care that much if people want to insist on saying "SSTO" when they mean "spaceplane"; it's a game! - my preferred approach for everything is dedicated SSTO launch/recovery vehicles, separating mission-specific space payloads once in orbit. If the payload's meant to stay up the launch vehicle returns alone, otherwise it hangs around until the payload does 'whatever', redocks and they go back down exactly as they came up. Unlike panzer1b, I wouldn't dream of making a SSTL because I can't see the point - that's what space-only tugs are for (launched by SSTO) - but then he's playing a very different game to me.

As to KerikBalm's original question - I'd say if drop-tanks work for you, use them proudly; it's not a SSTO any more, but so what, it's reusable and cost-effective and that's what you're after, isn't it?

[GoSlash27]

I don't argue much about SSTO definitions. Generally (not always) I am able to deduce the author's intention simply by context.

For me personally... I have a very strictly defined set of criteria for when and why I use SSTO spaceplanes vs. when I don't.

From a practical point of view the SSTO spaceplane only makes sense where

1) minimum operating cost and maximum safety are desired

2) the trip is strictly between KSC and LKO

3) Whatever is being transported can be transferred through a docking port

and

4) I plan on using it routinely

For everything else, I opt for different launch systems.

Best,

-Slashy

[Red Iron Crown]

I wouldn't dream of making a SSTL because I can't see the point

It's a stunt and a challenge, which can be fun too. It's not for any kind of Serious Business space program (which is a different kind of fun).

Making silly and pointless things is an old and honorable pastime in KSP, sometimes you just want to see what is possible even (or especially!) if it doesn't make a ton of sense.