Advice on 1st Boosted Glider Rocket

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BigMacDaddy

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I'd like to build a RC-controlled boosted glider rocket. I have looked at a bunch of the beautiful Dynasoar Rocketry models but would like to try to scratch build something but have some questions. Be gentle, new to this...

CP-CG: Where do you want CG in the glider for gliding phase post launch? I understand that just like most rockets, it helps to have CG as far in front of CP as possible during launch. However, it seems like you want CG to be just a little in front of CP when it is gliding. Is there a guideline for this? Stuff I have read for RC planes etc... talks about complex positioning of CG in relation to wings etc... Can this be simplified to a CG-CP relationship?

Manufacturing Materials: I know that most of the Dynasoar models use foam board for wings. I would like to make a slightly smaller model that launched on D or E engines. Can I build with 2mm basswood fins or is it really much easier to construct with foam wings?

RC Controls: I am assuming I would put two independent pitch controls on either of the "wings" that would allow positive pitch (i.e., range from flat to upwards pitch). Basically it seems that you pitch the glider upwards to get it gliding once it starts its decent and then can steer things by letting up on either of the pitch controls. Is this the simplest best control setup to start with?

Model: I am still trying to select a model to build. I assume that bigger wings are easier for the glider part. Would a Boeing Bomarc be a good model? I have one of those I built already and could maybe add the RC parts and flaps to wings or tail (although would need to remove some nose weight). I would like to make an X-15 but that has smaller wings. I also would like to make a Lockheed A-12 which would be another option or maybe some other supersonic jet.

1632677463568.jpeg

Anyway, any advice is appreciated - sorry about the long set of questions.
 
I hate to say it but you're making the classic mistakes of trying to design a rocket glider without having any RC airplane experience which you need to have also you're looking at things like a bomarc or an x-15 or an a12 which have narrow wingspans and typically high Wing loading instead of trying something that's simple that has a larger wing it's going to be more forgiving on boost and glide. You wouldn't learn how to fly a real airplane in a P-51 or a jet start out with a high Wing trainer same applies in RC rocket gliders. I would stay away from basswood as it's fairly heavy even at the thinner thicknesses. I'm not sure sure why you're specifying do your emotors without even having a design why pick the motor before you have an idea of the size and weight that you want it to be at?
 
My first plane was a P-51 Mustang. Made by Dynaflight. I liked the color Sky blue, so made it that. It lived 13 seconds. Listen to Frank.
 
I hate to say it but you're making the classic mistakes of trying to design a rocket glider without having any RC airplane experience which you need to have...

Ok so I should build an RC plane first and learn to fly it?

I also do not mind making the glider from foam just need to purchase it and have plenty of 2mm basswood so was wondering if it is possible...

I was setting the engine size since I do not necessarily care how large this boosted glider is and do not want to have to use composite engines. Prefer to stick to stock Estes for the engine if possible.
 
You don't have to build it, you can get a ready to fly plane but get something that will fly at a speed and have the same controls as you will build and get confident in it. It depends on how you build the model whether or not you care about the motor size, you have to worry about boost speed and strength, and where is the motor in the tail or on the CG or ahead of the CG? If in the tail you care a lot about the weight. Estes black powder motors have a non insignifican failure rate with a lot of fire and pressure which is not good for an RC machine you design and build and have a lot of $$ invested in. They also have very short burn times which means your trim has to be perfect and your reactions have to be quick, the advantage of using a long burn composite motor is you have nice long burn and easy boost speed and less stress on the airframe, that's why I design to those specifically. I have never had one fail in the 18mm and 24mm sizes, just this weekend in about 30 24mm estes E-12 and E-9 flights I saw about 5 catos.

There is a lot more to design and construction on top of this, I'd suggest get a plane or two and get comfortabe flying and landing deadstick with no motor power and judging your decent rate etc, then look at something that has worked very well and try to replicate that, and then get creative. There are a lof of ways to go wrong, if you look on you tube you will see a lot of idiots sticking bp motors on foam gliders and foamies etc, they get a lot of views because they fail and that's what people like to watch.

Frank


Ok so I should build an RC plane first and learn to fly it?

I also do not mind making the glider from foam just need to purchase it and have plenty of 2mm basswood so was wondering if it is possible...

I was setting the engine size since I do not necessarily care how large this boosted glider is and do not want to have to use composite engines. Prefer to stick to stock Estes for the engine if possible.
 
You are about 10 years too late, but look up the AeroTech Phoenix rocket glider. It has large wings and is designed to fly rather slow so that you can more easily control it. You would want something that can fly on either E6 or F10 motors. Low thrust long burn. Use this idea as a basis to start with. A Bomarc would be extremely difficult to fly...



1632759307587.png
 
I'm more a fan of performance over "looks cool" . . . Too bad that NCR no longer makes the North Hawk RC Boost Glider.

Of course, knowing that the glider has a 24" wingspan and is 22" long, would make cloning, via photograph scaling, a viable option.

The instructions are still available here . . . www.apogeerockets.com/downloads/PDFs/north-hawk-instructions.pdf

1632765114835.png


NCR-NorthHawk-RC-BG-RBG-glider.jpg

NORTH COAST - NCR - HAWK RC GLIDER - 1.jpg

NORTH COAST - NCR - HAWK RC GLIDER - 2.jpg
 
You are about 10 years too late, but look up the AeroTech Phoenix rocket glider. It has large wings and is designed to fly rather slow so that you can more easily control it. You would want something that can fly on either E6 or F10 motors. Low thrust long burn. Use this idea as a basis to start with. A Bomarc would be extremely difficult to fly...

That was not the motor the Phoenix was designed around, the G8 was developed... three? years ago now. I would definitely say that boost was underpowered, flying more like an airplane than a rocket. I had a bum E6 a few years ago that ended up being more like an E2. It had just barely enough thrust to keep the glider moving upward and that actually made it harder to fly.

The 32mm (yes, 32mm) RC G12, F13, F16, and F23 motors that the Phoenix was designed around definitely give it a heftier boost.

@BigMacDaddy, I like the Horizon Hobby ultramicro offerings for stick time. If you've got a reasonable backyard or park down the street, they work great. You can't beat stick time.
 
CP-CG: Where do you want CG in the glider for gliding phase post launch? I understand that just like most rockets, it helps to have CG as far in front of CP as possible during launch. However, it seems like you want CG to be just a little in front of CP when it is gliding. Is there a guideline for this? Stuff I have read for RC planes etc... talks about complex positioning of CG in relation to wings etc... Can this be simplified to a CG-CP relationship?
STABILITY.JPG
 
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