ok i think i might have got some people a bit confused here. I do mean using the rocket engines as propulsion not to actually fire off, that would be a stupid thing to do.

Also its not something i was planning or anything, it just cropped up in a conversation and i wondered if anyone else had tried anything like this.

Sorry if it kind of upset some people

oh and yes i would expect the plane not to survive and i would be using it in a VERY large clear area. I just thought it would be a fun thing to try out, kind of like adding an afterburner onto a model plane jet turbine, just one of those interesting things

Ideally i would like to mount a small hobby rocket motor thing in the back of my new power slope soarer. It would be good to use it to get up real high and fly around for a while considering i dont have many slopes around where i live.

7) I will not operate models with pyrotechnics (any device that explodes, burns, or propels a projectile of any kind) including, but not limited to, rockets, explosive bombs dropped from models, smoke bombs, all explosive gases (such as hydrogen filled balloons), ground mounted devices launching a projectile. The only exceptions permitted are rockets flown in accordance with the National Model Rocketry Safety Code or those permanently attached (as per JATO use); also those items authorized for Air Show Team use as defined by AST Advisory Committee (document available from AMA HQ). In any case, models using rocket motors as a primary means of propulsion are limited to a maximum weight of 3.3 pounds and a G series motor. Note: A model aircraft is defined as an aircraft with or without engine, not able to carry a human being.

so a fixed system (JATO) is ok by AMA.

fist off. dont put them on the wing tips. WHEN one ignites before the other it will send the plane into a spiral.

mount them on the back of the fuse. start with real small rockets to get the thrust angle right so you dont have it pitch up/down on you.

I do know that someone did this with a ZAGI foam wing with pretty good results... just take your time, dont do a "hack" job and it should work out for you.


oh.. and you can get model rocket engines without the chute charge in them. (estes rocket have a red and blue labels for them)

Unstable- good, informed response. I was about to type the very same things.

No need to talk about terrorism and what can't be done. JATO can be done, has been done, and will contine to be done. Just do as Unstable suggests with respect to placing rockets on centerline, not wingtips.

- George

phayad: If the Wright brothers had known exactly what they were getting into they wouldn't be considered pioneers.

As to the rest, I say go for it, but like everyone else has mentioned, do it away from everything.

I would definately NOT mount them to the wingtips. I would recommend building an apparatus similar to a model rockets business end and mount that in the tail. Or else mount the engine underneath the fuse, forward of the CG, so that if it affects your flight path at all, it will put you in a climb, not a dive. This will also let you aim the blast AWAY from your plane.

Be careful and take film!!

Frank

I've seen it done, though with one engine mounted under the belly of the plane. Rocket engines don't produce a ton of thrust anyway (A D engine will propel my 11oz rocket to about 100 ft) so I doubt you are going to rip the wings off or send your plane into an uncontrollable death dive. Keep the power reasonable for your first attempts (such as A motors) so you can get a feel of what your plane will do, then slowly increase the power.

Before youtry this in the air, rig everything up with igniters and make sure they will fire relatively close together. I don't think the ejection charge will adversly affect the performance, but you'll have to experiment.

"It is not because things are difficult that we do not dare; it is because we do not dare, that they are difficult."
-Anonymous

Didn't TF make an estes powered glider at one time? Used an estes rocket motor to launch it? Might have been someone else. Seems to me there was one selling though. A long time ago we though about loading a plane so we could fly it into a cliff at the lake and have it blow up and do a bunch of different angles with video. Would have been fun but judgement got he better of us and we didn't do it. 20 years ago, I wouldn't have thought twice. One of the bad parts of getting older, you think about the consequences.

the AMA states that a rocket cant be fired from a aircraft, but i suppose that it can be fired while attached to a plane and fired up. it would be neat to see, but please be safe and do experinets first like find out thrust, and what kind of effects it would have on the plane.

Always seems to be a newbie with a trainer asking this question. That's not good. you need to have quite a bit more experience with these things before you start doing stuff like this. Eveidence: You suggested the wing tips for mounting, the worst place possible to mount 'em.

Hey, I'm all for you trying to learn - and do this at some point. I'm just saying you have a whole lot more to learn. Get back to us in about 5 years.

The guy that flies the rocket boosted X-1 that's dropped from mac Hodges' B-29 has plenty of experience, I'm sure:

vtol-guy,

I dont know how much room you need to try this experiment, but assemble the rockets to the trainer as planned, then turn on your plane and radio (engine off), ignite the rockets and see if you can control the plane with rudder and elevator on the ground. If you can, then you'll have an idea of what to expect in the air, at least thrust wise.?!

Wish I could be there...too bad your not closer to my field, you could try it here.

this has been done at www.traderc.com check it out!!

ok thanx for everyones responses. I think what i'm going to do is probaly get a rocket starter kit just to get more used to rockets ect. After that i'll buy a small rocket motor thing and attach it to the back of my power slope soarer to help take it off. Depending if it works well or not i may then go on furthur to experiment putting them on other planes

johng

I may be young but dont doubt my experience. I'm a competant flyer and have designed some very impressive aircraft. My VTOL plane flew just yesterday and its first test flight is great. Others i know who have divulged into these type of planes have been modelling for at least 20 years. I may only have a few years expeience but i'm modelling every night of my life. Don't be prejudice against young modellers because its people like you who put other youngsters off the hobby, i should know!

Anyway dont forget the main rule of thumb to this hobby

"your never stop learning"

So how about you learn to treat younger modellers with more respect, and not tag them with the title of "newbie" and i'll carry on learning/experimenting with mounting rockets on model aircraft

I'm 15 and i've seen young kids about 11 who can fly with much better than me and other modellers who are older.

Sorry to other people about this very defensive post but I have very strong opinions on the subject of some few older modellers prejudice of young modellers.

Oh and one last thing, i have a GCSE's A grades in propulsion, aircraft handling, airmanship, princleples of flight aircraft navigation and aircraft communications.

Yeah, you got me there. :devious:

Six years spent organizing and conducting the Aerodesign intercollegiate competition - and continuing to volunteer in the 4 years since, or the handfull of teenagers I've tought to fly over the years, or the high-schooler I'm currently mentoring thru trainer construction as a school project have me thinking it's you who is prejudiced in this case.

Now, maybe you could tell us all what else you know about me. Like how "old" you think I am. That should entertain.

AS for respect, that is something that is earned. Although I didn't say anything insulting or inaccurate in my previous statement, it is obvious that you do need more experience. That has nothing to do with your age and everything to do with the know-it-all attitude and over-sensitivity expressed in your last post. You didn't earn any respect from me with that.

Now, post some of your designs - make sure you show us that VTOL - and you'll get going down a more productive track.

oh and yes i would expect the plane not to survive

quote by me, post no. 27 incase you want to look it up

i dont think that shows anything to do with know-it-all attitude, i call it experimenting, i would try it, if it dont work then try and correct. If the wright brothers didnt experiment with many different airfoil designs ect, their kittyhawk may never have flown, therefore they would never have made the first controlled, powered aircraft flight.

also respect probaly was the wrong word to use, how about curtousy. Show curtousy to them and they'll repsect you.

As i have said a couple of times i know that i dont know much about hobby rockets, as said in my first post its something that came up in a conversation and i was wondering about it. To do this i would research and i would learn about hobby rockets. And also my reason for saying possibly the wingtips in the first place was because i thought it would be a pretty good place. Under the fuse is a possible fire risk, i hadn't thought things through propely with it before i posted, i wanted to get feedback from other people about rocket powered rc planes which a lot of people have given me very useful info.

just so you know too the following things i found insulting:

to be a newbie with a trainer asking this question
i'm just saying you have a whole lot more to learn
Get back to us in about 5 years.

I know the wings would not have been stonrg enough on there own too, i would have strengthened them.

I do have many designs for many different planes but i do not own a scanner unfortunatly and i dont want to spend god knows how long putting them on the computer by copying them just so they can be critisized for every single tiny problem.

Many plane designs have faults in them which get corrected along construction.

Also i dont think i know it all either, if every single bit of knowledge on rc planes was a 1000 page book for example, i dont think i've even made it past page 2, its a vast, vast world of rc knowledge out there, i dont even think any one person has 'read' over, lets say 100 pages for example, different people know different things.

Prehaps it want clear to you in my posts that i would intend to research it thoroughly before modifying any of my planes, for that i apologize.

I think the best thing now is to leave it as that as i didn't want this to turn into a big argument or anything. If you do want to carry it on then e-mail me or something and we'll try and settle things like that but i think it should be spared from the board.

To any moderators: If this topic carries on with arguments in it then please close it, its not the way i wanted things to go, thanks.

If East Yorkshire is in a different country than the USA (which I think it might be??) then what does the AMA, AMA safety code, or any other AMA issues have to do with it??

As someone has already stated, the Estes motors aren't THAT powerful. I've built a few 3 stage rockets in my rocketing days. They generally weigh MAYBE 100 grams when flight ready. That's an estimate, and probably a bit on the heavy side. No where NEAR the weight of a 40 size trainer. I usually used a fairly hefty "D" motor for the first stage and liftoff was usually relatively slow and graceful. The problem with putting thrust on the wingtips isn't one of wing strength (in this case), but one of aysemetrical thrust. You'll want all of your thrust to be along the centerline.

Also, the thrust from these motors only lasts a few short seconds, so dont expect to go blazing around the sky under rocket power.

Overall I'd love to see it done, but I think that just using one motor will be a bit underwhelming and basically "safe"

If you want to think big, the next step will be to put some stages in series to get a longer burn. Pick motors that have a longish delay to give you time to get yourself out of any trouble that you may have gotten yourself into, before the next motor kicks in.

Frank

Well, I agree on that point, no more arguments that is. I'm unsubscribing this thread.

Good luck, be safe

FLYBOY:
Estes and Aertech both produced some rocket gliders. I have the Estes Astro Blaster (canard design) but haven't flown it with a rocket engine yet because my field won't allow rocket engines. I have glided it down a hill and built a mount for a Cox Black Widow, but haven't flown that yet either. I'll try to fly it this summer.

ya never know till ya try, but that try might cost ya one, been there done that, Im 17 and built my own design thats still witing ti be test flown. so never stop trying idea, just onsider that maybe it might be better to leave it alone. but this rocket idea is neat, but im not willing to try it, all my planes are over powered allready, no need for more thrust, and the smoke, ill buy a smoke sysytem, but cant get the rocket noise, if ya do it, post some pics, i find it interesting.

vtol_guy - I think you'll be fine. People are just really paranoid right now. I do think it would be wise to first try this when no one is around, or at a private field just so you don't scare the sheepish people, or break any of the AMA laws of your regular field.

Now let's talk about why your plan might not work like it should. I really doubt that hobby rocket engines are made to strict enough standards that mounting them on the wing tips wouldn't cause an asymmetric thrust problem. However, I could be wrong since I've never tested any rocket engines on a test stand (well I once did when I was a young lad, but we won't talk about that ) So what I would do instead is get a small piece aluminum that's maybe 1/8" thick. This would be used to protect the belly of the plane. From there you could make a simple holster for the engines (I assume you want this to be "Cool" so two engines are a must )

This is just an idea that solves the heat issue, and asymmetric thrust issue. In any case, I would try to mount the engines as close to the fuselage as possible in case an engine fail to ignite.

Have fun, and be safe with your experiment. Don't let anyone tell you can't achieve something. Finally, the AMA laws are just for insurance purposes. You can break them all you want, but you won't be covered by their insurance. I get the feeling that a lot of people think the AMA is a government agency, and that you'll go to jail if your break their laws.

AMA rules are just to cover your butt when somthing goes wrong.
dont mount them in wing tips, figure out a way to d oit on the fus. that way there wont, if any, stress be on the wings.

vtol_guy,

I have missed the first three pages of responses here, and I haven't read them all. Sounds as though it got a bit heated. My feedback would be this: 1) this is not an outrageous idea 2) I would avoid mounting the rocket motors at the wingtips, for the reasons mentioned; get them on the thrustline 3) the typical model rocket motors are not so high in thrust that reinforcing your trainer would be necessary 4) if local rules allow, and common sense is employed, go for it, but kick the motors in at high altitude the first time, in case you get some pitch or yaw from them.

Good luck, and do post pictures, if they aren't incriminating.

banktoturn

now there was some advice--that is what you need to do.

What the AMA has to do with it???

If the guy is not in the USA, I guess I might start worrying about bobbies from Scotland Yard locking me up for driving on the right hand side of the road..

I don't think (wink wink) the AMA has a whole lot of say so in East Yorkshire...