On Tue, 18 Sep 2007 19:15:28 -0400, john
wrote:



There are a number of other things to consider when it comes to aviation
and metric. Flight levels... in feet. Runway distances and aircraft
performance figures in the US are all in feet. All the aircraft
instruments are in feet, inches or lbs/sq. in. When you have a working
system you stay with it unless there is a vast improvment with a new
system.

Remember the Gimli Glider

It's the same as some countries using 50 cycle ac power when
60 cycles is a lot better.

John
Gerry :-)}
London, Canada