So im building a rocket-plane...

[SlimeCrusher]

Yep, you heard right, a rocket plane, im using 3 cardboard tubes pasted together with glue and alot of paper (Because it becomes really strong when dry), i used 1 tube to make the cockpit, its not quite fancy but it has a retractable hatch in order to put a plasticine victim Kerbal in it. The 2nd tube is a part of the retractable hatch, i also plan to put a chute or something in it. The 3rd tube is the most important, it has room for the engine, its currently empty though, and that's the reason of this post:

A: Do i make a removable SRB-like engine to put inside of the 3rd tube, that i can remove, refuel and then re-install it on the plane

or B: Do i simply reinforce the insides of the 3rd tube with lots of aluminium foil and stuff, so i can simply pour the fuel inside of it without any removal.

Yes yes, i can use those rocket motors you buy in stores and all that, but in my country, as far as i know there are NONE of those stores anywhere. Im planning on using rocket candy fuel for this.

I could also make the plane RC controlled, but after seeing on how difficult it is to buy and set up everything, i better stay away from that... Im currently using all my understandings on aerodynamics that KSP and FAR teached me, it should be enough to keep a stable-ish flight... I just don't want to open the hatch and notice my plasticine kerbal is all crushed and with its head missing

[Sky_walker]

Im currently using all my understandings on aerodynamics that KSP and FAR teached me, it should be enough to keep a stable-ish flight...

I laughed.

Anyway: good luck and show us some pictures

[Wanderfound]

I thoroughly approve the spirit of this, but my boring-old-man status forces me to say: are you sure you know what you're doing?

Home-made rocket motors have a nasty habit of exploding at undesirable times, even when they're made out of sugar.

(assuming that you do know what you're doing, though, make sure you post plenty of photos here afterwards...)

[xenomorph555]

Words of advice:

Test engines many times so the results aren't random, this could save your plane and your life.

Fly the thing in countryside or equivalent to where your live.

Your have two choices of engine, powder or candy, powder is much easier and safer but will need more testing and resources (red iron, etc), personally I went down this road and it worked okay. Search for very finely done potassium nitrate possibly from a guy called Nick if you can find him. Oh and also icing sugar.

If you choose candy then don't worry of the level of fineness, BUT be careful making candy, most accidents happen here.

Personally I have never had an explosion, but always be prepared, build a containment wall around test place, have a water hose, etc.

DON'T GET CAUGHT, KEEP ATTENTION AWAY FROM YOURSELF!

Have fun and good luck!

[dharak1]

I made a plane form an airhogs titan that used two c6-5 engines. I have pictures if you want to see them and even a video but I'd have to edit it.

[K^2]

Home-made rocket motors have a nasty habit of exploding at undesirable times, even when they're made out of sugar.

Absolutely. When building a home-made rocket, your assumption should be that it will explode. And that it can happen at any time. Do not use metal parts. They generate shrapnel. Do not be anywhere near the launch pad or intended flight trajectory. Make sure you can take shelter if it deviates from intended trajectory. Make sure that anyone within range knows to do the same. Property damage and fire hazard should also be kept in mind.

Most importantly, if you don't have a lot of rocketry experience, I suggest finding someone who can help you at every stage, at least with some advice.

[SlimeCrusher]

Thanks for the tips guys!

Because i don't have a phone in wich i can take pictures and upload them to the interet, i will post a quick drawing on some blueprints to show what im doing. I don't think i will go for sugar yet, i preffer getting the whole thing finished and then start to find a suitable propulsion fuel.

Now the blueprints:

The things on the side of the wings aren't engine mounts, they're "struts" to keep the wing from moving as much, and yes, they're hollow, i know what "drag" is

Currently i have too much weight on the back so it wants to pull up, but i can fix that. I also made the wings slightly dihedral for better stability

[cantab]

I would make a separate engine that slots in. That way you can test your engine and plane separately before flying under power - engine on the bench, plane in a glide with an inert dummy engine for weight.

And yes, be careful with rocket fuel.

[linkxsc]

My first suggestion to you wihtout this info though, you say you might build it like an RC plane. Perhaps you might dump about 150-200 dollars (or whatever it would cost) for a cheap 4channel RC plane. There's lots of great ones out there, most are rather weak to breezes though.

As far as building the engine itself...

[SlimeCrusher]

My first suggestion to you wihtout this info though, you say you might build it like an RC plane. Perhaps you might dump about 150-200 dollars (or whatever it would cost) for a cheap 4channel RC plane. There's lots of great ones out there, most are rather weak to breezes though.

As far as building the engine itself...

I actually meant adding RC controls to the rocket plane itself, not making it an actual RC plane with propellers and that stuff.

I had an RC helicopter long ago, fun to fly, but it broke after 2 weeks after a crash I still have some parts i scavenged from it, 2 small lights, the landing gear and a random chip lol

[xenomorph555]

I wouldn't add rc controls, complex, expensive and could be dangerous (no sas).

[SlimeCrusher]

I wouldn't add rc controls, complex, expensive and could be dangerous (no sas).

Exactly what i was thinking, RC=Bad unless you're flying a low-ish speed aircraft

[TechnicalK3rbal]

Words of advice:

-snip-

DON'T GET CAUGHT, KEEP ATTENTION AWAY FROM YOURSELF!

Have fun and good luck!

You imply that they're illegal, are they?

(Homemade "candy rockets" for those of you who missed the rest of the thread.)

[mardlamock]

In most countries they arent illegal, this sounds hilariously fun dude, good luck!

[Wanderfound]

In most countries they arent illegal, this sounds hilariously fun dude, good luck!

OTOH, if you draw police attention with one of these then you're going to have an uncomfortable conversation whether you're technically legal or not. Folks are a bit edgy about home made explosives these days.

[linkxsc]

I actually meant adding RC controls to the rocket plane itself, not making it an actual RC plane with propellers and that stuff.

I had an RC helicopter long ago, fun to fly, but it broke after 2 weeks after a crash I still have some parts i scavenged from it, 2 small lights, the landing gear and a random chip lol

Well I was meaning if you were planning on doing a controllable rocket... but if thats not what you're going for.

Model rocket motors are great, and I've made them based off of this little guide before, and they worked kinda well.

http://balloons.space.edu/ndra/nickle.html

Musta shot off about 500 rockets of varying size based off that. But make sure that whenever you're doing anything with these rockets you keep a fire extinguisher handy, and safety is always the #1 priority. Worked great for little rockets, though we did some larger ones. Pay special attention to the "coring" part of the guide because if you don't get a fast burn... you just get a smokey flamey mess.

Couple other things, before trying your plane thing out, try for just some rockets. Get some papertowel tubes, or make rocket bodies with some craft paper.

We had done a couple "rocketplanes" a while ago that launched via 1 of these, but had full RC pitch and roll controls and you'd just kinda fly them on the way down, they worked great.

[linkxsc]

OTOH, if you draw police attention with one of these then you're going to have an uncomfortable conversation whether you're technically legal or not. Folks are a bit edgy about home made explosives these days.

Also, if you wanna draw police attention, get a few people together in a "public RC park" with control line fighters and do streamer fights with them. Cops start coming out of the woodwork when people start hearing the weedwackers from 1/2mi away, and then if you get a good 150v150mph head on collision while maneuvering, those little things sound like a car accident happened. Especially if you use metal spars for the wings.

[cantab]

In most countries they arent illegal, this sounds hilariously fun dude, good luck!

Illegal in Britain, for what it's worth. Making any sort of solid rocket motor yourself is regarded like making an explosive device and so heavily regulated it's out of amateur reach really. The ready-made motors are easy to get though.