0.24.2 SP+ (AKA soon-to-be-stock) JX-42 Vector - The VTOL SSTO Interceptor

[Levelord]

Greetings fellow Kerbonauts, it's been a while

I've been working on a replacement for the aging Amphibious VTOLSSTO and VTOLSSTO Marin fleets with new design goals reached. The only mod needed is Spaceplane Plus, and seeing as it's going to be incorporated into the game by the next update, this will eventually be a stock craft.

Goal #1 - Achieve a lighter weight than the Amphibious VTOLSSTO [✓]

Goal #2 - Achieve a faster flight to orbit [✓]

Goal #3 - Be able to land on uneven terrain and SSTO to orbit from Duna [✓]

Goal #4 - Be able to land in water and SSTO from Laythe [✓]

Goal #5 - Increase VTOL control ability [✓]

Goal #6 - Compatibility with the Marin interplanetary transfer vehicle [✓]

Goal #7 - Use air intake rules to prevent flameouts on either engines and prevent the need for air hogging. (Yes, there are no asymmetrical flameouts on this jet.) [✓]

Goal #7 - Probe control autonomy [✓]

Goal #8 - No CoM shift regardless of full or empty tanks, maintaining permanent VTOL balance [✓]

Goal #9 - Stock conversion come 0.25 [ ]

DOWNLOAD HERE

Controls:

1 - Toggle NERVA

2 - Toggle Dual RemJets

3 - Toggle Basic VTOL Jet

4 - Toggle Rockomax 48-7S (to be used to fine tune VTOL landings)

8 - Cut parachutes

9 - Deploy parachutes

0 - Extend antennae

Here are the craft dimensions.

Size comparison to the old VTOLSSTO. It is now lighter and more efficient.

Marin Interplanetary ring compatability.

Duna landing safety chutes (notice final landing speed, chutes slow down horizontal speed while Rockomax 48-7S slow down descent and allows for gentle horizontal landings.)

JX-42 Vector escorting the Marin VTOLSSTO to the alternate KSP airbase.

Future variants in testing:

Edited September 15, 2014 by Levelord

[Rune]

I will admit to having reverse-engineered this to stock, it's that awesome:

Now the question: is there some oxidizer I'm not seeing, or the likelihood of taking off to orbit again after touching down on Duna depends on using the VTOL engines very, VERY sparingly? Like, I only get 1,590m/s on nuke with the liquid fuel out, and a stable Duna orbit takes at least 1,5km/s. Or is it meant to be refueled before takeoff?

Rune. Only slightly worse looking.

Edited September 11, 2014 by Rune

[O-Doc]

Now the question: is there some oxidizer I'm not seeing, or the likelihood of taking off to orbit again after touching down on Duna depends on using the VTOL engines very, VERY sparingly? Like, I only get 1,590m/s on nuke with the liquid fuel, and a stable Duna orbit takes at least 1,5km/s. Or is it meant to be refueled before takeoff?

Rune. Only slightly worse looking.

I think you'll find there's a nuke tucked into an FL-T400 as the primary powerplant.

Levelord, love the Duna landing solution. My latest heavy lifter is currently doing through Duna trials and takes a similar approach using chutes and retros.

[Levelord]

I will admit to having reverse-engineered this to stock, it's that awesome:

http://i.imgur.com/MBKqACZ.png

Now the question: is there some oxidizer I'm not seeing, or the likelihood of taking off to orbit again after touching down on Duna depends on using the VTOL engines very, VERY sparingly? Like, I only get 1,590m/s on nuke with the liquid fuel, and a stable Duna orbit takes at least 1,5km/s. Or is it meant to be refueled before takeoff?

Rune. Only slightly worse looking.

It's meant to be re-fueled in orbit before going anywhere, which is also why I made some compatibilities with the interplanetary ring. I removed some oxidizer on the side tanks because they serve no purpose for Kerbin SSTO (where liquid fuel gets used more). Once in orbit, you can re-fuel it or link it up to an interplanetary drive and go anywhere.

It's not really necessary to reverse engineer it as you can obtain the basic bodywork by simply removing the wings, the original architecture is still intact. Then you can add wings as you desire and it will still maintain CoM stability. It will save more work on your end

From my initial testing, I typically glide down to Duna with full tanks and make a landing using minimal fuel. Once I'm ready to take off I make for an 80km orbit. There should be enough fuel for that

P.S. I'd love to fly your stock replica!

[Rune]

I think you'll find there's a nuke tucked into an FL-T400 as the primary powerplant.

Levelord, love the Duna landing solution. My latest heavy lifter is currently doing through Duna trials and takes a similar approach using chutes and retros.

Er... that was kind of a given. Hence:

I only get 1,590m/s on nuke

There is a typo, but that's an "out" after liquid fuel that I accidentally erased or something (or didn't write in the first place).

Edit: while posting this, Levelord kind of answered.

Rune. So my question stands, hidden tanks, propellant-less landing, or refuel before takeoff to make Duna SSTO?

Edited September 11, 2014 by Rune

[Rune]

It's meant to be re-fueled in orbit before going anywhere, which is also why I made some compatibilities with the interplanetary ring. I removed some oxidizer on the side tanks because they serve no purpose for Kerbin SSTO (where liquid fuel gets used more). Once in orbit, you can re-fuel it or link it up to an interplanetary drive and go anywhere.

It's not really necessary to reverse engineer it as you can obtain the basic bodywork by simply removing the wings, the original architecture is still intact. Then you can add wings as you desire and it will still maintain CoM stability. It will save more work on your end

From my initial testing, I typically glide down to Duna with full tanks and make a landing using minimal fuel. Once I'm ready to take off I make for an 80km orbit. There should be enough fuel for that

P.S. I'd love to fly your stock replica!

Yeah, but building it from scratch was far more FUN!! And of course I assumed you start in low Duna orbit with full tanks, I just haven't gone there enough to have very firm Delta-V figure for ground to orbit. The 1,590m/s I get with full LFO tanks and empty liquid fuel tank seemed a bit tight if you use some of it to soft land first, when the wiki says 1,500m/s-2,000m/s are required to make it. Then again, me and the wiki could very likely be overestimating Duna's gravity well. What's your practical figure for ground to orbit on reasonable T/W?

Rune. Oh, and I'll upload the file and send it to you if you want, or put it here, it's no trouble at all, so your choice.

Edited September 11, 2014 by Rune

[Levelord]

Rune. So my question stands, hidden tanks, propellant-less landing, or refuel before takeoff to make Duna SSTO?

Hm... I'm not sure what you mean by that, it doesn't need to re-fuel to SSTO from Duna's surface, and I can assure you there's only 3 tanks. No hidden tanks to be found! XD

My landing on Duna uses the parachutes and short bursts of the Rockomax 48-7S to level the plane out.

Perhaps it's the ascent profile? I point the aircraft nose straight up until I reach about 30-50Km before turning horizontal when I want to get back to orbit. I'll probably try to do a video during the weekend of it O_o

[Rune]

Hm... I'm not sure what you mean by that, it doesn't need to re-fuel to SSTO from Duna's surface, and I can assure you there's only 3 tanks. No hidden tanks to be found! XD

My landing on Duna uses the parachutes and short bursts of the Rockomax 48-7S to level the plane out.

Perhaps it's the ascent profile? I point the aircraft nose straight up until I reach about 30-50Km before turning horizontal when I want to get back to orbit. I'll probably try to do a video during the weekend of it O_o

No, then it is just that I overestimate a Duna liftoff, and probably also what it would take to slow down for landing. I for sure haven't tested myself! Which is kind of understandable, since my lack of serious timewarp use (still day 30 in my main save from 0.23) means all that interplanetary stuff is almost terra incongita for me. I do it mostly because there is always something else to launch while my ships are on the way, but it also means by the time 1.0 arrives, there will still be places I haven't gone to to explore. But in the meantime, I healthily overestimate any delta-v outside the familiar ones for the kerbin system where I test most stuff.

Rune. I'm in this for the long run!

[Levelord]

Here's the latest testing results from Duna's surface. I hyperedited the craft into a 80km Duna orbit. Used the NERVA to de-orbit and landed. Then took off again into a 80km orbit. It had about 125 units of liquid fuel in orbit, which is not bad!

I hope this helps!

P.S. Oh, and also post your craft here so I can try it out!

Edited September 11, 2014 by Levelord

[Rune]

One stock replica, coming right up!

http://www./download/9b324j9a4q2wo3m/SSTO+MK+XXXVIII.craft

I fiddled a bit further and added a standard-size shielded port instead of a redundant intake (attaching the engine with surface attachment saves me a fuel line and a structural piece, plus freeing a node on top of the aircraft's CoM and making the VTOL engine visible from the underside), so if the port looks a bit weirded out upon loading, cycle it so it snaps back into place. Also, I worked out the action groups and tested aerodynamic handling, landing on the VAB, on the pad, and on water prior to an unpowered gliding landing with full tanks and conventional takeoff. Superb on all of them (notice I didn't have the chutes on yet, the brakes on, the position and alignment I ended at, and the "autosaving" in the screenie from having just landed after an extended flight).

And I might end up downloading yours and taking a KER delta-v readout myself. Just to check the weight of SP+ wings, I guess.

Important edit: Well now I get it. Your central tank is LFO! That would significantly change things, I see now. How dumb of me! Sigh... Redesign coming up...

Edit of the edit: Rebuilt. The new download has twice the LFO mix capacity, and is now a true replica including performance. Took far less time than I thought, this intake business of having to place all one by one may end up saving time in the end.

Rune. Kudos on a very good original idea!

Edited September 11, 2014 by Rune

[Levelord]

I've done some safety tests using the whack-a-Kerbal cheat to knock off some random flight surfaces from the vehicle. The Jx-42 proved to be remarkably stable despite this and was able to make a safe water landing without much trouble.

[Rune]

Did you get a chance to look at my thing? I'd be interested to hear how close to yours I got with just a few pictures and stock parts.

Rune. So you had hidden wings... my "cheat" was heavy use of Ed Extensions besides the liberal clipping.

[Levelord]

Did you get a chance to look at my thing? I'd be interested to hear how close to yours I got with just a few pictures and stock parts.

Rune. So you had hidden wings... my "cheat" was heavy use of Ed Extensions besides the liberal clipping.

I had a good look at your plane, and I'm surprised how well it flew. It had a better roll force than my plane! I haven't made it go to orbit yet, because I was having too much fun buzzing the SPH tower.

There's only a slightly small thing involving the action groups where the #4 action group would only enable the left Rockomax 48-7S, but that is easily fixed

[Levelord]

Made a quick and dirty video of the craft.

[The14th]

A very cool video for a very beautiful looking craft

[Rune]

I had a good look at your plane, and I'm surprised how well it flew. It had a better roll force than my plane! I haven't made it go to orbit yet, because I was having too much fun buzzing the SPH tower.

There's only a slightly small thing involving the action groups where the #4 action group would only enable the left Rockomax 48-7S, but that is easily fixed

Thanks! I take it I got it about right, and yeah, I did it rushed so it's no surprise I forgot about resetting action groups for the VTOL engines (pretty much the only thing besides tanks set with symmetry, hence the "bug"). It's one of the reasons I'll never be able to play without "reset to SPH", I ALWAYS forget something of the short, like action groups, staging, power generation, is it crewed and you want it so?... I should make a checklist, but that big green button always beckons a bit too much.

The video is awesome, BTW, and the antenna heatshield a very nice touch I had totally missed.

Rune. If only I had the broadband to do video in anywhere close to reasonable time... I'd probably suck at it. ^^'

[inigma]

awesome craft, as always. you inspired the formation of SSI, btw.

[speedboiae86]

Took this for a test flight today. My only qualm, no action group for shutting all the intakes at once. I also experienced an asymmetrical flame out when the intake air dropped below the jet engine's functioning threshold. But other than that, it's a great little ship!! She's quite peppy!!

100th post hype!!

Edited September 16, 2014 by speedboiae86
100th post hype!!

[Rune]

Took this for a test flight today. My only qualm, no action group for shutting all the intakes at once. I also experienced an asymmetrical flame out when the intake air dropped below the jet engine's functioning threshold. But other than that, it's a great little ship!! She's quite peppy!!

100th post hype!!

I also found that with the replica. It's the ship I started applying the intake air flow rules to, and I think now I get it. Long story short, keep at it, once you empty the intakes (0.1-0.0 intake air on the resources tab), the thrust will even out and you will regain balance until final flameout, at under 10% effective thrust. You will actually notice how the engines stop glowing and keep on thrusting... but yeah, you have to fight it for a second or two, thankfully it has a great SAS torque versus inertia momentum relation. It's cool that ability to prioritize air flow from each intake to different engines. If only you could do it without knowing so much SPH kung-fu .

Rune. I seriously should release something of my own to answer questions about...

[Levelord]

The conversion to stock in 0.25 has proven more tedious than anticipated. There has been several changes to some part weights and landing gears are no longer massless. This will take a while. ETA will probably be in the weekend and I'll be creating a new thread for it.