What additional information is needed to know if this mocked up system will work?
Is this CHAD system safe?
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What additional information is needed to know if this mocked up system will work?
Is there a gap in there between the booster and the sustainer? Do you need vent holes?
Also in the second pic it looks like the booster motor is drooping down a bit. Is the coupler sufficiently robust?
Other than that I don't think there's all that much to CHAD staging. As long as the rocket is still stable (probably not a problem for your long skinnies) then go for it.
Also in the second pic it looks like the booster motor is drooping down a bit. Is the coupler sufficiently robust?
Other than that I don't think there's all that much to CHAD staging. As long as the rocket is still stable (probably not a problem for your long skinnies) then go for it.
No gap between the motors. Coupler is quite robust. Could drop down to a much lighter 18mm booster and lose the coupler. CG is about at the 36" mark. 24 square inches of fin area. Rocket with sustainer weighs 3 oz. With 18 mm booster it would be fairly close to 4 oz, hence the interest in the 24mm booster with another 2 oz headroom.
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Normally I would say not, but your rockets are very long and probably conservatively overstable, so you can probably get by with it.
one risk may be weathercocking (which may paradoxically be LESS with the CHAD stage, but if it does go off vertical at separation that’s a fresh new motor lighting at near Vmax velocity, ejection may occur far lateral from the launch point. may be a long walk, and your rockets have no waving parachute or streamer so may be a challenge to find on the ground, especially if it recovers outside your field.)
question: WHY?
are you staging for extra altitude?
HSR is EXCELLENT for boosters (as @lakeroadster recently demonstrated.). So you could build an HSR booster, it doesn’t need to be long, it’s gonna be unstable and will start tumbling than spinning almost from the get go. It will however be even MORE likely to weathercock than the CHAD version.
May be hard to find a lone casing. not sure what your launch site rules are on policing your motor casings (my former site in Tennessee didn’t care, the casing are biodegradable and much less noticeable than a lot of trash that gets left by careless park users.). I doooouuubt your field will be a problem if you ”lose” a single use paper motor casing, but may want to check with @BEC or others that use the park, I am finding the local parks in a Vancouver are not particularly rocket-friendly.
one risk may be weathercocking (which may paradoxically be LESS with the CHAD stage, but if it does go off vertical at separation that’s a fresh new motor lighting at near Vmax velocity, ejection may occur far lateral from the launch point. may be a long walk, and your rockets have no waving parachute or streamer so may be a challenge to find on the ground, especially if it recovers outside your field.)
question: WHY?
are you staging for extra altitude?
HSR is EXCELLENT for boosters (as @lakeroadster recently demonstrated.). So you could build an HSR booster, it doesn’t need to be long, it’s gonna be unstable and will start tumbling than spinning almost from the get go. It will however be even MORE likely to weathercock than the CHAD version.
May be hard to find a lone casing. not sure what your launch site rules are on policing your motor casings (my former site in Tennessee didn’t care, the casing are biodegradable and much less noticeable than a lot of trash that gets left by careless park users.). I doooouuubt your field will be a problem if you ”lose” a single use paper motor casing, but may want to check with @BEC or others that use the park, I am finding the local parks in a Vancouver are not particularly rocket-friendly.
I have been interested in bringing HSR to the larger tube sizes, BT-50 and up, mainly for the purpose of better visibility from the ground. When we get our BT-20 models up to 700' and higher, they become more difficult to observe the ejection event and generally keep track of. Yet the HSR models I've launched with BT-50 and BT-55 tubes have suffered a higher rate of fin damage upon landing. I am attributing this higher damage rate to the higher weight of the model and to the 24mm engine casing. Accordingly, I'm thinking I can get these larger models a bit lighter with 18mm motors and getting my altitude with the aid of a booster. Other factors that matter are getting tight spiral descents and improving fin design and construction - but these matters are best discussed elsewhere.
To continue with staging matters, the question arises of how much impulse is required for a given lift weight. Let's say I have a 3.2 oz upper stage. A B6-0 CHAD booster will add 0.55 oz weight and on paper will provide enough lift for the resulting 3.75 oz model. But the B6-0 is rated for only 4 oz of lift weight. Is that prudent? Would a C11-0 with 6 oz lift ability be the wiser choice?
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