My wife bought me a Wildman Sport for birthday and I launched it three times on Saturday at our club's model launch. Two launches were on F20-4W that I have had for a couple years. Then the third was on a G76. All three great flights and seemed a good shakedown prepping for high power launch next weekend.
But... the two flights on F20s were much lower then simulations would suggest. Thrustcurve comes up with 736 feet and OpenRocket puts it at 716. (One note is that OpenRockets indicates F20EJ not sure if it is the same.) Anyway, my actual altitude according to an Estes altimeter was 475 and 510 feet. Unfortunately I didn't get a reading on the last flight.
I really don't mind if the rocket is that much more draggy then the initial guess. But the Cd calculates out to over 2 as compared to initial estimates of .6 or .75 supplied by the programs. My only real concern is that I would like to get the delay as close as possible.
Anyway, would the age of the motors explain the difference in altitudes? I would gladly put another load in to test, but not sure if there is much point since the delay might still be off quite a bit and ejection at high speed could occur.
But... the two flights on F20s were much lower then simulations would suggest. Thrustcurve comes up with 736 feet and OpenRocket puts it at 716. (One note is that OpenRockets indicates F20EJ not sure if it is the same.) Anyway, my actual altitude according to an Estes altimeter was 475 and 510 feet. Unfortunately I didn't get a reading on the last flight.
I really don't mind if the rocket is that much more draggy then the initial guess. But the Cd calculates out to over 2 as compared to initial estimates of .6 or .75 supplied by the programs. My only real concern is that I would like to get the delay as close as possible.
Anyway, would the age of the motors explain the difference in altitudes? I would gladly put another load in to test, but not sure if there is much point since the delay might still be off quite a bit and ejection at high speed could occur.