Eggtimer Rocketry Eggtimer User Manual page 38

You can clearly see that the rocket hits peak altitude at about 10 seconds, and maximum velocity at
about 3 seconds. Note that the velocity graph is jaggedy compared to the altitude graph; this is due
to the aforementioned issues with deriving velocity from barometric pressure. The important thing
is that you can see clearly where the velocity peaks then drops sharply; this is where the motor
burned out and aero drag immediately started to slow the rocket. You can also see where the drogue
ejection charge fired about a second after apogee and the rocket starts to slow. The CHA (main)
channel fired at about 44 seconds (44000 ms) at about 200'. If you look at the velocity graph, you
will see disturbances where the ejection charges fire; this is because the jerk of the parachute coming
out causes a short pressure "bounce".
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