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Old 05-08-2009, 08:04 PM
jgonza jgonza is offline
Junior Rocketeer
Join Date: May 2009
Location: missouri
Posts: 9
Default altitude predictor

I use mark sullivans altitude predictor to figure the flight characteristics for my rockets. The problem is the delay that is given is often a second or more too long. I build my rockets with aerodynamics in mind. no sloppy fillets and smooth paint why would the delay be so wrong. ex. 47mm body, 457.2 mm chute 353g liftoff weight with a f39-9 motor. the site i use gives 8.1 seconds from ignition to turnover, motor burns for 1.3 sec. so adelay of 6.8 should be appropriate, yet it falls for 1.1 seconds when i use a 7 sec delay, is the predictor innacurate or am i missing something?
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