For rocket team last spring we used the calculations from this site - http://www.rocketmime.com/rockets/descent.htmlCookiePie1 wrote: ↑January 21st, 2020, 7:34 pmSorry, but how did you calculate this? and, theory tends to be quite different than practice in build events, especially one as complicated as parachutes.Airco2020 wrote: ↑January 21st, 2020, 7:00 pmbuilderguy135 wrote: ↑January 20th, 2020, 2:56 pm

lmao this was only a month ago. aren't people getting just under double that already?

If you scroll down on that page you can use the red calculation for velocity: v = sqrt( (8 m g) / (p r Cd D2) )

Where

D is the chute diameter in meters

m is the rocket mass in kilograms

g is the acceleration of gravity = 9.8 m/s2

p is 3.14159265359

r is the density of air = 1.22 kg/m3

Cd is the drag coefficient of the chute, which is 0.75 for a parasheet (flat sheet used for a parachute, like Estes rockets), or 1.5 for a parachute (true dome-shaped chute).

v is the speed we want at impact with the ground (3 m/s or less)

You just need to multiply the v which is in meters/sec by 3.281 to get Feet per second. If the claims are true you need .5 ft/sec in this calculation.

I know there are some people flying outside - and who knows what that means for times. And some of the gyms I've been in feel like a tornado - so maybe you can catch an updraft. It's also a bit hard to estimate height in the gym or exactly how high the rocket went on a launch, so there might be some error in reported numbers because of that. But to get .5 on this calculation you need to be around 2 meters and 5 grams unless you can build a super light dome shape (real) parachute and then you still need 1.5M.