On Sunday, May 11, 2014 3:01:30 AM UTC+12, wrote:
I went through the spread sheet and I found everything correct except for the calculation of the "enhanced sink rate". The sink rate is not just the unbanked rate multiplied by the load factor!

Ahh . yes .. you are correct. That's right for the descent angle, but then you need to adjust that by the ratio of the airspeeds to get the descent rate.


Some manufactures include a circling polar. Using the circling polar of an asw-24 with a total weight of 750 lbs, the speed and sink a

at 30 deg: 45 kt, 150 ft/min
at 45 deg: 50 kt, 205 ft/min
at 60 deg: 59 kt, 345 ft/min

With the correction of multiplying the sink rate by "speed needed"/"min sink speed" my spreadsheet gets the above numbers (and same turn times and height loss) for a glider with a min sink of 122 fpm at 42 knots.