Approach Timing

On 9/7/04 4:02 PM, Brien K. Meehan wrote the following:

Mitty wrote:

Doesn't seem like the MAP is that important.


On an instrument approach, it's the most important thing in the world.


So what if you are a bit
early or late when you decide you can't see where you're going?


You'd better study this a bit, because if you manage to get through
your IFR checkride without busting it a bit, this attitude may soon
make you dead a bit.


I don't want to turn this into a flame war, but I'll take the bait he

How (calculator, flight computer, mentally, etc.) and how precisely,
during an approach, do you calculate your time to the MAP based on your
ground speed crossing the FAF? Finally, to you, what is an acceptable
"bit?"

My checkride went fine, thanks.