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Regarding comments by @Alan15578 and @tjkopena
On my part, ignorance can be bliss, as I have never flown single stage HPR and certainly not multi-stage. I do consider myself (FWIW, probably not much) one of the more experienced rocketeers in long gap staging rockets with black powder staging and no electronics.
My main experience WATCHING High Power was NSL 2019, and while I did watch one HPR rocket do a complete (and quite frightening) 360 degree vertical loop (or at least close to 360, fortunately it straightened out with a net trajectory at least 45 degrees vertical and away from the spectators), it seemed to me like HPR rockets seem to have less of a problem with weathercocking than LPR. That may be simply because I haven't seen as many HPR launches, or it may be because HPR builders take velocity off the rail more seriously than LPR builders (and unfortunately LPR Kit designers), and HPR builders have the range of motors to get adequate speed off the rail, LPR far more limited.
For all practical purposes, all model rockets are fin stabilized, no gimballed motors like the real space rockets. With the exception of @Daddyisabar , most staged rockets have their motors in their tails, so they require more finnage or more nose weight to achieve stability. The combination of more weight and more surface area makes getting the stack "up to speed" off the rod or rail challenging for both HPR and LPR, but HPR has (I think) a lot more flexibility in motor choices to do it right. For LPR on the Estes side all we have is A10-0 (not bad), A8-0 (pretty bad), B6-0 (okay for very light loads), C6-0 (mediocre at best), and 24 mm C11-0 (never used it so can't say much), and D12-0, which I really like and is my go-to for anything remotely complicated. For those kits which Estes designs with 18mm booster mounts (LoadStar and MIRV come to mind), weathercocking is a MAJOR issue.
I absolutely agree with you guys that an appropriately delayed booster to sustainer ignition is far more efficient in many cases than immediately igniting sustainer at booster burn out. I am not sure about most efficient way of getting more altitude in HPR, maybe staging makes more sense than just sticking a bigger motor in the a single stage bird, and DELAYED staging in combination with electronic safety lockouts is da bomb (well, maybe that's not the best word choice, but anyway it's cool AND efficient), but I feel pretty confident that for a LPR L-0 like myself, if I really want more altitude, I am better off going with a bigger motor than with staging, in large part because of the weathercocking tendency. At least for LPR, this is increased for two reasons. First, a lot more finnage on the tail to get blown sideways. Second, with our limited motor choices, adding more fins adds more drag, and adding more nose weight likewise is going to drop my speed off the rail. So whereas for HPR, you just say, add more fins or add more nose weight, the HPR guys and gals have the motors to handle it and (hopefully) the electronics to do it safely. And for pure black powder staging with no electronics, again IMO adding ANY delay is just begging for trouble, since we have no altitude or tilt lockouts. So staging Low Power is mainly just for the fun and cool factor, not so much about altitude.
In a way, Low Power Black Powder non-electronic staging is kind of like the old fuse type model rocket ignitions. This type of ignition was appropriately disallowed by the safety code for at least one good reason (there may be others.) Between the time you light the fuse and the time it lights the rocket, something bad may happen, like the wind knocks the launch pad over, or someone blunders into the launch area. With electronic ignition, you have the ability to abort pretty much right until lift off.
Black Powder staging is kind of the same way. Yeah, the stack on pad is straight and aimed (hopefully) in a good direction, but you really DON'T control the attitude and altitude of the rocket with certainty when it stages, but if you put it together right, it's GONNA stage regardless.
Please correct any errors in my reasoning above, particularly my comments about HPR, as much of that is me hypothesizing, I have no real experience with it, although I enjoy reading @JimJarvis50 stuff, it's really cool even though I am never going to do anything remotely that complex.
On my part, ignorance can be bliss, as I have never flown single stage HPR and certainly not multi-stage. I do consider myself (FWIW, probably not much) one of the more experienced rocketeers in long gap staging rockets with black powder staging and no electronics.
My main experience WATCHING High Power was NSL 2019, and while I did watch one HPR rocket do a complete (and quite frightening) 360 degree vertical loop (or at least close to 360, fortunately it straightened out with a net trajectory at least 45 degrees vertical and away from the spectators), it seemed to me like HPR rockets seem to have less of a problem with weathercocking than LPR. That may be simply because I haven't seen as many HPR launches, or it may be because HPR builders take velocity off the rail more seriously than LPR builders (and unfortunately LPR Kit designers), and HPR builders have the range of motors to get adequate speed off the rail, LPR far more limited.
For all practical purposes, all model rockets are fin stabilized, no gimballed motors like the real space rockets. With the exception of @Daddyisabar , most staged rockets have their motors in their tails, so they require more finnage or more nose weight to achieve stability. The combination of more weight and more surface area makes getting the stack "up to speed" off the rod or rail challenging for both HPR and LPR, but HPR has (I think) a lot more flexibility in motor choices to do it right. For LPR on the Estes side all we have is A10-0 (not bad), A8-0 (pretty bad), B6-0 (okay for very light loads), C6-0 (mediocre at best), and 24 mm C11-0 (never used it so can't say much), and D12-0, which I really like and is my go-to for anything remotely complicated. For those kits which Estes designs with 18mm booster mounts (LoadStar and MIRV come to mind), weathercocking is a MAJOR issue.
I absolutely agree with you guys that an appropriately delayed booster to sustainer ignition is far more efficient in many cases than immediately igniting sustainer at booster burn out. I am not sure about most efficient way of getting more altitude in HPR, maybe staging makes more sense than just sticking a bigger motor in the a single stage bird, and DELAYED staging in combination with electronic safety lockouts is da bomb (well, maybe that's not the best word choice, but anyway it's cool AND efficient), but I feel pretty confident that for a LPR L-0 like myself, if I really want more altitude, I am better off going with a bigger motor than with staging, in large part because of the weathercocking tendency. At least for LPR, this is increased for two reasons. First, a lot more finnage on the tail to get blown sideways. Second, with our limited motor choices, adding more fins adds more drag, and adding more nose weight likewise is going to drop my speed off the rail. So whereas for HPR, you just say, add more fins or add more nose weight, the HPR guys and gals have the motors to handle it and (hopefully) the electronics to do it safely. And for pure black powder staging with no electronics, again IMO adding ANY delay is just begging for trouble, since we have no altitude or tilt lockouts. So staging Low Power is mainly just for the fun and cool factor, not so much about altitude.
In a way, Low Power Black Powder non-electronic staging is kind of like the old fuse type model rocket ignitions. This type of ignition was appropriately disallowed by the safety code for at least one good reason (there may be others.) Between the time you light the fuse and the time it lights the rocket, something bad may happen, like the wind knocks the launch pad over, or someone blunders into the launch area. With electronic ignition, you have the ability to abort pretty much right until lift off.
Black Powder staging is kind of the same way. Yeah, the stack on pad is straight and aimed (hopefully) in a good direction, but you really DON'T control the attitude and altitude of the rocket with certainty when it stages, but if you put it together right, it's GONNA stage regardless.
Please correct any errors in my reasoning above, particularly my comments about HPR, as much of that is me hypothesizing, I have no real experience with it, although I enjoy reading @JimJarvis50 stuff, it's really cool even though I am never going to do anything remotely that complex.
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