"Mxsmanic" wrote in message
...

snip
If I'm asked how long it will take to go 84 nm at 120 kts, I know that
it's
about 40 minutes, but if an exact answer is required I don't see how I
could
practically provide that without a calculator.

your kidding! 120 kts = 2 nm /min exactly 84 nm = 42 min exactly

and even if it wasnt a nice round number , didnt you ever learn long
devision in primary school?

Personally I do most of my flight planning in Excel. but if I havent got a
computer with me, I always have a calculator in my flight bag.
For doing calculations in the copckpit , I do it all mentally. In all my
flying ( 200 hrs) I have never used a calculator or whizwheel in the air.
If say I have to do a diversion , I estimate distance off the map using the
old rule of thumb and I know my TAS in nm/min. I might use a protractor to
measure the
track, if I am not particularly busy, but normally I can estimate the track
with 10 degrees off the map which is usually accurate enough, when you have
adequate landmarks. I carry a GPS with me but only for "just in case"
terry