We used to put ZFW in it - It then gave max alt etc along with climb/descent speeds (and assumed temp for T/O too...)
The thing is, we all used to ignore the descent speed, figures below 250 were common on a light aircraft with a tailwind!
And yes, speeds around .72 to .73 were common.
Ed to add - It also did cruise speed (as above) with a headwind/tailwind feed from the nav box (if it worked! ;-) )
Last edited by Cough; 10th Jun 2014 at 15:03.