Squadcast confirms SABRES for 0.23!

[thescientist]

Yahoo! [as always 10 characters]

[kiwiak]

That will require putting different amount fuel and oxidiser in tank. Guess thats what twekables are for.

Or we will use different tanks for fuel and oxidiser?

I wonder if we woudl be refill empty oxidiser tank or just use atmosphere air in-flight.

[Boris_T_Roach]

C7's update exactly confirms what Wikipedia lead me to believe -- that's awesome and I might finally build my first SSTO! (Yeah, right! )

You will always build more than 1 SSTO because the first one always ends up as bits of debris in a direct line with the end of the runway

Spot where the SSTO experiments happen...

http://cloud-2.steampowered.com/ugc/1136285831817524563/84CA5E2E5D6C7E3B2E2C95075901252BC5F1EC27/

Boris

[Hodo]

This kind of Sabre?

But I suck at making SSTOs, even with B9 sabres, so doesn't mean much to me

I love B9 SABRE engines....

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108 ton cargo capacity to orbit SSTO.

And now with VTOL abilities.

[Corw]

That will require putting different amount fuel and oxidiser in tank. Guess thats what twekables are for.

Or we will use different tanks for fuel and oxidiser?

I wonder if we woudl be refill empty oxidiser tank or just use atmosphere air in-flight.

You can do this right now, just mix rocket tanks (fuel and oxidizer) and jet tanks (just fuel).

[Urban_K]

As long as they keep them balanced, then I'm ok with it. (It should be lighter than carrying both a rocket and a jet, but perform worse than both in their respective uses).

Exactly. They also should give only a little thrust at low speeds in air breathing mode.

[Merinsan]

Does that mean spaceplanes finally become viable without air hogging? Because that is the one thing that kept me from making them, I always felt stupid when I started stacking intakes and decided to wait for properly balanced spaceplane mechanics.

Quite easy to make a spaceplane now withowt airhogging. I've done one with about 4 intakes only. It's just a matter of piloting it correctly.

[jsfalconero]

It's just a matter of piloting it correctly.

Piloting alone is seldom sufficient to cover for bad engineering. It IS possible to build an SSTO with only four intakes, but it needs to be both built and flown differently. You're probably looking at a smaller craft, one jet engine, higher TWR on the rocket and more dV in the rocket stage, correct? Different SSTO concepts are going to require markedly different construction styles to be viable regardless of how they're piloted.

I wind up airhogging (to my shame) because it allows me to build larger craft which adds versatility. I don't know how the SABRE engines will change that for my play style, but I know I'm looking forward to it.

[Brofessional]

I've done one with about 4 intakes only. It's just a matter of piloting it correctly.

My most reliable SSTO only has two intakes. You definitely don't need air hogging to make a successful SSTO.

[Vrana]

.... It IS possible to build an SSTO with only four intakes, but it needs to be both built and flown differently. You're probably looking at a smaller craft, one jet engine....

I guess this is a matter of opinion, in mine four intakes for only one jet IS airhogging.

I limit myself to max 2 intakes per engine which must not be on top of each other. No need to build small either. More jets, more wings, more rockets makes for higher payload. So long as i dont use more then 2 intakes per jet i do not feel i airhog.

Then again it has been a long time since i built a stock SSTO. I did go back to check if what i said was true back then too.

Edited December 7, 2013 by Vrana

[jsfalconero]

lol, I suppose it's sort of like suggesting a 'proper' ascent profile for a rocket. There are lots of things people agree on (Gravity turn... it's a good thing), but heaven help you if you think you're going to get away with posting the 'best' ascent profile (don't try, trust me on this, that's a can of worms right there).

On the flip side to what I said before, looking at the ship Brofessional posted earlier makes me yearn for the days when my SSTO's weren't stupidly overcomplicated and delicate. I've never built one quite that simple, but I seem to have forgotten the rule of maximum parsimony in favor of, "if I do it this way, I can do THIS thing that SSTO's weren't meant to do."

[CommandantAce]

My most reliable SSTO only has two intakes. You definitely don't need air hogging to make a successful SSTO.

How does this thing work? I built it and the CoL is so far in front of the CoM it flips over. Just had to try it. My two ker serviceable SSTO is a beast of a lady.

[jsfalconero]

I just had a go at reverse engineering it. My center of lift wasn't too far forward. My first attempt had too little dV -had to circularize with RCS, but it made it. Fun little plane, but it is a tad tricky to fly, and it can't glide to save your life (RIP Jeb, lol)

[Eric S]

It was also mentioned here: http://forum.kerbalspaceprogram.com/threads/59746-Devnote-Tuesdays-No-Sleep-til-Kerbalkon

(under C7's section)

Slight (and possibly wrong) clarification. The dev notes described the possibility of sabre engines without a plugin, the stream strongly implied that we'd also get a STOCK sabre-like engine. That we'd get a stock engine at some point that took advantage of this was likely, but this makes it sound much more likely to turn up in 0.23.

The stream went on to imply that cleaning up the spaceplane parts (including adding cargo holds) might just get bumped up in priority because of this engine. They said that how much of a craft returns to Kerbin will affect the budget for your next launch, and that this type of engine is going to make SSTOs more feasible. We all expected that some fraction of the cost of the parts that return would go back into the budget, but this is the first I've heard where the devs are actively talking about it and the implications it will have.

[flightmaster]

This kind of Sabre?

Nope, this kind of SABRE

http://en.wikipedia.org/wiki/SABRE_(rocket_engine)

from this kind of vehicle

http://en.wikipedia.org/wiki/Skylon_(spacecraft)

[Hodo]

Exactly. They also should give only a little thrust at low speeds in air breathing mode.

The B9 SABREs are like this. The largest of them creates just over 850kn of thrust in jet mode at Mach 4.95, at Mach .5 it creates about 125kn and weighs 6 tons. When in rocket mode that same SABRE generates 740kn of thrust. Somewhere between the Mainsail at 1.5Mn, and the Skipper at 650Kn, yet it is heavier than both. By Mach 5.9 the airbreathing mode becomes useless, and it generates maybe 50Kn of thrust and dies out completely by Mach 6.2ish.

[Hodo]

I guess this is a matter of opinion, in mine four intakes for only one jet IS airhogging.

I limit myself to max 2 intakes per engine which must not be on top of each other. No need to build small either. More jets, more wings, more rockets makes for higher payload. So long as i dont use more then 2 intakes per jet i do not feel i airhog.

Then again it has been a long time since i built a stock SSTO. I did go back to check if what i said was true back then too.

I have made it to orbit with a 1:1 ratio, but found it is horribly inefficient so I use now a 3:1 ratio on almost all of my SSTO space planes. That is no where near airhogging because I can find real life examples of that exact ratio.

[Dispatcher]

I've an SSTO plane with a single turbojet with 7 air intakes, but it looks decent and does not involve the use of part clipping or stacking; an alternate design has 8 intakes.

In reading about SABRE and Skylon, I'm wondering about the engine's curved front to rear design. Is that to conform to the Skylon wing cross section or to take advantage of some shape related engine characteristic?

[Spyritdragon]

Has nobody here ever flown the Aeris 4A? Its a very simple stock plane yet makes a reasonably smooth SSTO at only one RAM intake per engine.

[katateochi]

As long as they keep them balanced, then I'm ok with it. (It should be lighter than carrying both a rocket and a jet, but perform worse than both in their respective uses).

absolutely. I really hope that this doesn't suddenly make SSTO planes easier.

I can already think of thirty-six uses for a SABRE.

this should be interesting!

[Blaster]

absolutely. I really hope that this doesn't suddenly make SSTO planes easier.

this should be interesting!

Remember that this is a rocket engine that uses air for oxidizer, so it will still have the ISP and performance of a rocket engine, but the ability to pull air from the atmosphere to use as oxidizer until you get near space. If anything, SABRE engines will work great for SSTO Rocket Rockets too.

[Col_Jessep]

You can build fun SSTOs with SABREs. And they are not just limited to planes either:

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[Killerdude8]

Jet efficiency, Rocket power, No combination quite like this one.

[Brofessional]

How does this thing work? I built it and the CoL is so far in front of the CoM it flips over. Just had to try it. My two ker serviceable SSTO is a beast of a lady.

It uses clusters of 48-7S engines, 4 on each side. If you used aerospikes or something else it won't work.

[Monger]

Has nobody here ever flown the Aeris 4A? Its a very simple stock plane yet makes a reasonably smooth SSTO at only one RAM intake per engine.

I barely makes it into Orbit, without any mentionable payload. I tried to build on the Aeris 4A to include a second seat, but as it turns out you need a very different design for this.

The biggest problem currently is that all available air breathing engines are that big and heavy, and therefore are really hard to balance. Integrating everything into one engine should make things considerably easier, especially for small planes.