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Rocket carriers


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So, any moron can build a rocket with a plane around it. Baby stuff.

I want to build a plane with a rocket on the top. I\'ve attached my 'most working' design. By this I mean the design that doesn\'t immediately fall to pieces when you press launch.

It doesn\'t do too well. It goes careering off the runway (as most of my planes do for some odd reason) and if it manages to survive that and stay in one piece until it\'s airborne, the second it does get airborne it does backwards flips that don\'t look even physically impossible. Maybe my wings are in the wrong place or something ;/

Most of the time, either the decoupler breaks and the rocket falls on the plane, some part of the plane falls off, or some parts of the rocket fall off.

I do have a working design that is similar to this except that it works. But it can only carry a rocket with one fuel tank, and that isn\'t enough to get into orbit, sadly (at least with my lack of skills). Really I want 2, 2.5 or maybe 3 tanks.

I really wish the parts wouldn\'t just fall off that way when horizontal when they work perfectly bloody well vertical. Bah!

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Perhaps there are too many control surfaces? I notice you have both canards and elevators. I always assumed it was in most cases a one or the other type situation (can\'t think of any real aircraft that use both - not that I\'m an expert). I do know that the canards in KSP do enable some slightly hyper manoeuvrability which is very difficult to control, even in precision mode.

I\'ve even played around with leaving off ailerons - the command modules generate enough rotation to roll even fairly large planes, and I\'ve found it more controllable in a lot of cases.

I\'m just guessing here, really - I\'m away from my KSP enabled laptop, Anyway, someone who knows what they are talking about will be along shortly :)

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To address your first problem, it\'s not at all uncommon for planes to veer like yours. Mine do too. This isn\'t your fault at all. It\'s caused by the way the game handles collision. The parts all have their own collision meshes, and like colliding with each other, even if they\'re on the same craft. This can pose a problem by pushing the craft off course. On planes, where it\'s more pronounced due to atmosphere and the smallish wing parts, it\'s best handled by a good SAS (preferably ADV SAS) unit or trim. (For realism, I like blaming it on crosswind.)

The second has a little more to do with design. Look at IRL air launched craft like SpaceShipTwo / WhiteKnightTwo. They always carry the payload below the fuselage, in the case of the Pegasus micro launcher, or below the wing, as in the case of SpaceShipTwo. This is so that the craft can be dropped before lighting the rocket engines, so that it maximizes distance between carrier and payload, thus minimizing the chances of a collision. Example pics are attached.

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Your centre of lift might be too far forward, judging by the position of your wings. The centre of lift should be near your centre of gravity. Think of a side-view of your plane as a see-saw, and the wings/centre of lift are the point where it\'s balanced. Try moving the wings backwards if it\'s backflipping, and forwards if it\'s frontflipping. Keep the payload (the rocket) close to the CoL and CoG too.

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Thanks for the ideas.

Well I put the wings further back and made some other tweaks and it kind of flies okay... But won\'t go high enough/fast enough that the rocket is sufficiently out of the atmosphere to not be affected by drag and brought straight back down. Any attempt to add half tanks and aerospikes to make up for it, but then it\'s heavy and falls apart.

I think a big part of the problem is that currently when building horizontally there isn\'t enough strength in that orientation for everything to not just fall apart, which is pretty annoying. It makes it ridiculously frustrating to put something together that looks totally fine, but the wings fall off. Struts help this fine, but if the rocket falls off... Not much I can do about that. Hopefully that\'ll get fixed.

Of course I could make rocket powered but this, well, mostly defeats the purpose :/

I can\'t really put it underneath. Well I can, but t\'s a bit more complex to get takeoff right without smashing it up. I\'m also concerned that since I\'d no longer have control over the plane after separation, that well, it\'ll all go tits up with things going crashyboom.

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I don\'t think deploying from the bottom is practical at all because the diameter of the rockets vs. the height of the landing gear isn\'t quite how it is IRL. The fuselage of aircraft IRL is usually much bigger than the rocket itself. Take fighter-launched Anti-satellite missiles, for instance. If you deploy from the bottom, you also face the problem of the aircraft being uncontrollable. Most of the time it will pitch down into your now-accelerating rocket.

I found with my HADS - High Altitude Deployment System, which was a huge carrier that launched a Vanguard shuttle into orbit (I later discovered Vanguard no longer flies straight in 0.15 D:< ) I mounted the rocket over the wings and it worked out okay. That was a heavy launcher, and my launch strategy was to not climb too steep until I got to around 10km, then accelerated as fast as I could and did what\'s called a zoom-climb - if you don\'t know what that is, you speed up as much as possible then trade your speed for altitude even after your engines flame out. I think my final deployment altitude was around 17km, and initially your rocket burn should be straight up as if you were doing a standard ascent, to get you out of the thicker atmosphere. I made two successful deployments like this before I got bored of the treacle-handling bug with small craft decoupled from larger ones.

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Hmm. You don\'t have the craft file lying around do you? I wouldn\'t mind looking at a working example that doesn\'t fall to bits.

I prefer sort of minimalist designs but at this point I\'ll take anything really.

Assuming it\'s all stock parts anyway =P

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Uhhhhh... like this? 8)

If you were one of the people above saying how it was nearly impossible to do a rocket carrier or that 'I don\'t think deploying from the bottom is practical at all' person please test this out and slap your brains out thinking 'why didn\'t I think of that!?'. I managed to do this with STOCK PARTS!

(not picture look for it below)

HOW TO USE: since it is slightly off angle to the runway, do not activate ASAS when lifting off (would also not let you take off) then go at about 45 degrees. when you go horizontal, activate the two aerospikes and point up. when they become useless, deactivate the turbojets. then use it like an ordinary rocket/point up to get an apex above atmosphere and then burn horizontal. Capable of orbit.

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The spaceplane industry is way ahead of you. That isn\'t decoupling from the bottom, that\'s a twin fuselage with the rocket decoupling from the middle. I believe this was first demonstrated either by Stratolaunch or SpaceShipOne.

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GoodGuy, that is pretty damn nice.

Being overly huge and complex it\'s not really to my tastes though... But I would like to know how you build something that big without it just falling apart on the runway like everything I make seems to. I see that there\'s a lot of strutting going on, but whenever I try to strut things, it usually makes them worse, it seems like the struts are pulling things apart :(

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I only just noticed your engine-wing layout. Your aircraft is much heavier than it looks, because those jet fuel tanks with the wing-mounted engines are worth 2.4 Mass x2 for each wing. That\'s probably causing structural issues because you have 4.2 tonnes + the mass of the engines supported by the wing boards. Try using the much lighter structural fuselage.

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