Kerbodyne SSTO Division: Omnibus Thread

[Jovus]

I usually land around 100m/s as well, but I was jockeying for position, and then decided to see how far I could push it and keep it in the air.

[Hodo]

I usually land around 100m/s as well, but I was jockeying for position, and then decided to see how far I could push it and keep it in the air.

That is pretty fast, I usually land around at 70-80m/s. Some of my faster designs land about that speed of 90-100m/s but they are usually still VERY stable at those speeds.

You may want to look at your glide slope on those landings. If your rate of decent is higher than 10m/s and your flight path indicator is lower than 3deg below the horizon and your angle of attack is higher than your take off AoA then you will probably have a tail strike issue.

Most of the time my landing is about 10deg AoA, -3deg glide slope, and rate of decent of OF -5m/s and -8m/s. I can touch down smooth as silk and keep the nose up, till the nose wont stay up any more, then I let it ease down and then I hit the brakes. Usually going about 40-50m/s at that point and it is pretty easy to stop from that.

[Jovus]

Hodo, I definitely can land at lower speeds; I just also can usually land at speeds up to 150m/s, and I don't see any reason to wait if I can keep my vertical speed under control and have enough runway. I pretty much never land with a vertical speed greater than -6m/s, though.

[Hodo]

Hodo, I definitely can land at lower speeds; I just also can usually land at speeds up to 150m/s, and I don't see any reason to wait if I can keep my vertical speed under control and have enough runway. I pretty much never land with a vertical speed greater than -6m/s, though.

I try not to land over -6m/s but I have one craft that once it hits 70m/s it falls out of the sky. But hey it will do mach 2 at sea level.

[Wanderfound]

I usually land around 100m/s as well, but I was jockeying for position, and then decided to see how far I could push it and keep it in the air.

All of the Gull/Skua derivative airframes have nice low-speed low-altitude behaviour; the dihedral-tipped long wings seem made for it.

[Wanderfound]

The latest in our bulk passenger range: the Kerbodyne Kosciuszko. Fast, luxurious, unstoppable.

Annotated long-range flight test album at http://s1378.photobucket.com/user/craigmotbey/Kerbal/Kerbodyne%2025/Kerbodyne%20Kosciuszko/story

Craft file at https://www.dropbox.com/s/4v4rkcnvk7pk0rp/Kerbodyne%20Kosciuszko.craft?dl=0

[Wanderfound]

Kerbodyne Kosciuszko Laythe mission report part 2: http://s1378.photobucket.com/user/craigmotbey/Kerbal/Kerbodyne%2025/Kerbodyne%20Kosciuszko/Laythe%20Landing/story

[TheAnimePug]

This thing sems rather heavy i have a lighter design that can get you to minmus easy GG without refeul and maybe even to duna ill upload it later

[Rakaydos]

This thing sems rather heavy i have a lighter design that can get you to minmus easy GG without refeul and maybe even to duna ill upload it later

Probably not with 24 passangers, and not out to Laythe.

[Wanderfound]

Probably not with 24 passangers, and not out to Laythe.

Flies like a sportster, too; that Wedgetail/Farseer airframe is one of my favourites.

Almost all of the nuke ships here can do KSC-Minmus-KSC without refuelling; the longer-ranged of the non-nuke stuff should be able to do so as well.

But, OTOH: if you're building spaceplanes, then you're probably advanced enough to put some orbital infrastructure in place. Orbital refuelling allows interplanetary travel without the need to launch ponderous behemoths, and greatly increases the reach of spaceplanes in general, so why not use it?

Unrefuelled to Jool in this one, BTW: http://s1378.photobucket.com/user/craigmotbey/Kerbal/Challenges/SSTYC/story

[Wanderfound]

Got a nifty spaceplane, but got nowhere to take it? Need an orbital refuelling station put in place fast? The Kerbodyne Instant Infrastructure range is what you're after. Invest in quality now, reap the profits later.

Album at http://s1378.photobucket.com/user/craigmotbey/Kerbal/Kerbodyne%2025/Kerbodyne%20Instant%20Infrastructure/story

Craft file at https://www.dropbox.com/s/nwrrdck8u6vubxp/Kerbodyne%20Instant%20Infrastructure.craft?dl=0

[Red Iron Crown]

I'm confused by that propellant depot, judging by this pic it looks like it consumes most of its LFO getting to orbit.

[Wanderfound]

I'm confused by that propellant depot, judging by this pic it looks like it consumes most of its LFO getting to orbit.

It does; hence the caption on that pic. Putting up a station like this, you can either have something relatively elegant and low part count that uses its fuel load to emplace itself, or you build a gigantic monstrosity that delivers a pre-filled station to orbit. The second option is much more expensive.

The idea is to put the station into position with the tug (AKA the KR-2L launch engine), using the station's own fuel to do it. Then, send up a few spaceplane tankers to refill the station, and make a habit of having your returning ships drop off their excess fuel before deorbiting. The station doesn't need to be 100% full at all times; so long as the spaceplane tanker supply flights keep pace with demand it's all cool.

The infrastructure is bulky, and therefore needs an expensive rocket launch (which you don't want to have to do more often than necessary, so best make sure the tanks are big enough for all future needs...). The fuel isn't, so it can go up on cheap-to-run spaceplanes.

Edited December 8, 2014 by Wanderfound

[Red Iron Crown]

Ah, I see. I've been going the other way, I launch a depot with the intent of having it arrive in orbit fully fueled, mostly because I can't be bothered with tanker runs to fill it. I can see how you've traded some time doing tanker runs for greater efficiency, but wouldn't it be more efficient still to have the tanker be the refueling station?

[Wanderfound]

Ah, I see. I've been going the other way, I launch a depot with the intent of having it arrive in orbit fully fueled, mostly because I can't be bothered with tanker runs to fill it. I can see how you've traded some time doing tanker runs for greater efficiency, but wouldn't it be more efficient still to have the tanker be the refueling station?

My refuelling tankers are usually rather expensive and high-part-count spaceplanes (so I don't like to leave them lying around), with big fragile wings and only one docking port that isn't as accessible as it might be. And, although they're amongst the biggest spaceplanes I build, they've got nowhere near the fuel capacity of an orbital station. A dedicated fuel depot is just nicer to have, IMO.

This is all assuming campaign mode, of course; in sandbox I'll just Hyperedit the things into place wherever I need them.

[Jovus]

Flight report for an unmodified Kerbodyne Skua:

First, I should say (and it comes as no surprise) that it performs as advertised: a very nice plane all around for getting light cargo loads up to LKO and doing orbital rendezvous. Well done, Wanderfound. There are just two things of note, and one suggestion.

I noticed on the way down, around 30km going Mach 3 there is a touch of instability with a not-exactly-empty plane. Nothing unresolvable, but I had to be more careful with the inputs than I at first thought (amounting to, for a moment, almost having to worry about half as much as flying my own planes).

On the way up the handling is great; however, the monoprop tank doesn't allow LF/O to flow across, so the rear RAPIER chokes as soon as it exhausts the fuel in the adapter. I don't really see a use-case for that much monoprop, so what you could probably do is just replace it with an LFO short tank (or a short cargo bay, though the weight difference will probably be more extreme). Its low-altitude, low-speed is if anything even better than the Gull.

...now I need to see if I can recover from the Hell Kraken, or if I'm just waiting for 0.90 to come out.

[Wanderfound]

Gah; that fuel flow / cargo bay bug is annoying. Fuel hoses or Goodspeed can route around it.

Mach 3 is really too slow for that altitude; over 30,000m is hypersonic territory. During reentry, I'd drop below 30,000m as soon as I get under Mach 5.

BTW, while you're in a flight testing mood, give the Infusion Corsair a poke. I was quite happy with that one, but it didn't draw a lot of attention. Thin fuel margins, though; I'm working on a slightly enlarged version now.

Edited December 9, 2014 by Wanderfound

[blowfish]

In my own testing I've noticed unshrouded LV-Ns producing a lot of drag in FAR (maybe because of the unused attach node on the back...). Have you noticed this at all?

[Wanderfound]

In my own testing I've noticed unshrouded LV-Ns producing a lot of drag in FAR (maybe because of the unused attach node on the back...). Have you noticed this at all?

Not just LV-Ns:

However, notice the lack of drag on the intakes? I don't know exactly what's going on, but I wonder if somehow the intake drag is being shifted to the engines.

Nathan or Ferram would be the people to ask.

[Fingal]

Wanderfound, this thread and your work has finally got me into spaceplanes and I'm loving it! Thank you

[MainSailor]

...but I wonder if somehow the intake drag is being shifted to the engines.

I've been flying a slightly modified Farseer and I'm seeing the same thing on the Rapiers. I thought it was just a funny rendering bug on the shader since the drag value shown in the pop-up didn't seem extraordinarily high. I'll see if I can get some screenshots next time I play.

I've also noticed that at some speeds and altitudes, the coefficient of lift shader just refuses to show...like the whole aircraft is producing no lift, even though even at Mach 4 and ~20-25km it still out to be making lift somewhere. I'm chalking it up to the KSP shader and not FAR's code, as I've seen similar fuzziness with TAC's highlighting too.

[Wanderfound]

I've been flying a slightly modified Farseer and I'm seeing the same thing on the Rapiers. I thought it was just a funny rendering bug on the shader since the drag value shown in the pop-up didn't seem extraordinarily high. I'll see if I can get some screenshots next time I play.

I've also noticed that at some speeds and altitudes, the coefficient of lift shader just refuses to show...like the whole aircraft is producing no lift, even though even at Mach 4 and ~20-25km it still out to be making lift somewhere. I'm chalking it up to the KSP shader and not FAR's code, as I've seen similar fuzziness with TAC's highlighting too.

Keep in mind that lift and drag are both heavily influenced by AoA. Are you testing by pitching up in these "no lift" situations?

[MainSailor]

Are you testing by pitching up in these "no lift" situations?

No I actually think it's a glitch with the shader. I still make lift according to the right click stats. Just the shader doesn't show anything.

[Wanderfound]

First flight test of the Kerbodyne Kosciuszko VTOL:

Full story at http://s1378.photobucket.com/user/craigmotbey/Kerbal/Kerbodyne%2025/Kerbodyne%20Kosciuszko/Kerbodyne%20Kosciuszko%20VTOL/story

[Wanderfound]

Sales of the Kerbodyne Dropbear have been brisk enough to convince our sales team to try and saturate the market with similar vehicles so that the Dropbear construction line can get some rest. Therefore, our latest release: the Kerbodyne Kosciuzsko VTOL.

Craft file at https://www.dropbox.com/s/qbmxoxan61lm0zx/Kerbodyne%20Kosciuszko%20VTOL.craft?dl=0

Flight test at http://s1378.photobucket.com/user/craigmotbey/Kerbal/Kerbodyne%2025/Kerbodyne%20Kosciuszko/Kerbodyne%20Kosciuszko%20VTOL/Final%20test/story