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  • #16
    Originally posted by elaw View Post
    2) This will probably make it obvious I'm not a mathematician, but I'll take a crack at it...

    To go down 600 ft. in 60 seconds, obviously you need to average 10 ft/sec during the descent. To get the smoothest descent, you will want to increase descent rate steadily during the first 30 seconds, then decrease it steadily during the following 30 seconds. And I think if you do that, the average descent rate will be half of the peak rate achieved at the 30-second point. Therefore the peak must be double the needed average, or 20 FPS (well technically -20 FPS).

    Following the steady increase/decrease formula, that means you need a downward acceleration of (20 FPS / 30 seconds) or 0.6667 Ft/Sec^2 during the first 30 seconds, then an upward acceleration of the same magnitude during the second 30 seconds. Both of those numbers get added to the 1G gravitational force experienced by the aircraft during straight & level flight.

    0.6667 Ft/Sec^2 equates to about 0.0207 G. Factoring in the normal effect of gravity, that means that the aircraft (and of course the pax) would experience a vertical acceleration of (1 - 0.0207) = 0.9793 G during the first 30 seconds, and (1 + 0.0207) = 1.0207 G during the second 30 seconds.


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