"C Kingsbury" wrote in message
link.net...

"Steven P. McNicoll" wrote in message
news:ze1ad.13857

Being off by 50' in cruise wouldn't be noticed.


OK, to be precise, 100'+/- is OK, and encoders click over at 51', right?
So
you'd have to be 151' off for it to show as outside tolerance. Fly over
some
building cumulus in a 172 sometime- that can left your skirts 100' before
you know it. Better have that altitude nailed or you've violated your
clearance.

Hell, I remember vertical deviations of a lot more than that, with the VSI
being dam near pegged on the climb/descend scale in some sizeable twins,
during some turbulence.

I was on an Embrarer 55 out of Houston and heard the warning horn going off
in the cockpit during turbulence that I think got us zero gravity at a
couple of points.