Cunning,
27.5 minutes, because one has to "catch the cabin" at 200ft so that the machine doesn't land pressurised. 130nm is a tad too far away, but that's what you have to do for 300ft/min. We "use" 500ft/min (as you know??!!) so we descend closer in than 130nm. Descent points being too close? Don't get me started!
Itchy,
It may be OK for for ex-RAAFees, but Joe Public wouldn't know what the valsalva manoeuvre was (and neither, possibly, do the "experienced" chooks in the back) so the first thing they know is they have sore ears or worse.
Besides, pax in pistons were probavbly so terrified of what might happen generally they didn't worry about their ears!
737 Drivers,
What does happen to your cabin rate of descent if you descend late? Does it/can it exceed 500fpm or this simply not possible because of descent path/drag issues?