How long does the average tandem skydive last from door to floor?

There is a formula that works quite well. The first 1000ft takes 10seconds. This is because the initial velocity with respect to the ground is zero so therefore the average velocity to this point is half terminal. Thereafter, it takes 5 seconds for every 1000ft.

Therefore a jump from 12000ft will give you 7000ft of free fall with a deployment at 5000ft. That is 10 sec to 11000ft, then 6 times 5 seconds to 5000ft, a free fall period of 40 seconds.

Keep in mind a heavier Tandem passenger will have a bit less time, and a small Asian woman or a child will have a bit more.

More bang for your buck, call Jenny Craig. Check out the Tandem Instructors and go for the smallest. That will give you a bit more FF.

Because of the lower air pressure at higher altitude, this formula is not quite so good for 16000ft or 20000ft Tandems.