AboutDave Landgraf Expertise I will be happy to take on questions about low-power rocketry in general, including rocket design, operating characteristics of blackpowder motors, low-power motor selection, rocket construction, aerodynamics, parachute and streamer duration competition, boost glide (and a little rocket glide), egg loft, altitude competition, and scale competition. I can help you with Barrowman stability calculations, but I am not a rocksim user. I know the basics of mid-power rocketry and small composite motors but I don't fly them much (I'd rather stretch my money by sticking with low-power). I believe I can explain many concepts in a way that just about anyone can follow (and maybe even over-explain?). I absolutely do not mind "newbie" questions one bit; the only bad question is the one you don't ask!
Experience I have flown model rockets for some 40 years, including a few early years of NAR competition. I have been active at the local club level as well as in the NAR. I enjoy designing and developing unconventional designs (the kind of thing you look at and say "it won't fly!").
Organizations National Association of Rocketry
Publications Model Rocketry (magazine)
Education/Credentials I am an aerospace engineer who has worked professionally in the field for over 30 years. I have worked often with local school, church, and scout groups to lead introductory build-n-fly sessions.
Question Hi Dave I'm trying to build a sequential launch controller where I would only have to push one button and the controller would launch four to six rockets in sequence and I was wondering if you had any ideas. Thanks, Brian
Answer Hello Brian,
I will say right up front that I am not great at circuit design, and there is probably only a 50/50 chance that anything I might sketch out would work as intended. I apologize if this sounds like a run-around but I strongly encourage you to check in at The Rocketry Forum (http://www.rocketryforum.com/) with this question. It is completely free to view and to post, and I know there are several guys there who can get you the proper help. If you don't like TRF, some other great places for questions like this would be at YORF (http://forums.rocketshoppe.com/), or at ROL (http://www.rocketryonline.com/modules.php?name=Forums). These other websites are also completely free.
I do know enough to point out one safety issue (you may have also thought of it) with a launch system such as yours; you will need a great big "kill" button to immediately cease the operation of the launch system and hold back any remaining model rockets. The reason? Do you remember the safety code, and the prohibition about not launching into airspace occupied by aircraft? If your automatic system is started just before a low-flying aircraft appears, you will certainly need a way to cancel the ignition signals to any rockets still on the pad.
Or, if a gust of wind blows over the launcher in mid sequence, and it is pointed at YOU (or anyone else, for that matter), I think you will want it to stop launching rockets.
So you can probably understand if I urge you to include a kill switch?
I hope you can find some better help at the places I suggested.
