--"gwengler" wrote in message
om...

I am just repeating from what I read in the FLYING Magazine (Richard
Collins). He said basically that datalink capability in the airplane
ON THE GROUND is pretty much irrelevant since you get all the weather
you want 2 minutes before engine start in the FBO or on your internet
laptop. Makes sence to me...

That plan does not work if you are departing from a small airport without a
weather computer.

That plan also does not consider that many airports do not pay for the
5-minute WSI weather feed and instead have 20-30 minute old weather in their
flight planning room. Assume the FBO weather is 20 minutes old and it takes
10 minutes to startup and another 10 minutes to taxi and another 10 minutes
to receive in-flight Bendix/King weather and all of a sudden the pilot is
working with almost 1-hour-old weather data and maybe now has to call ATC to
ask for a weather deviation. Imagine how much easier it is to get
5-minute-old weather data anytime during taxi and climb out.

Also that plan ignores the time at low altitude when the weather data is
unavailable; in some regions of the country the Bendix/King system is
unavailable below 5,000 feet, and lots of IFR planes spend considerable time
below 5,000 feet when weather decisions are important.

Perhaps most important of all, the unavailability of the data on the ground
means the pilot loses the ability to use the weather datalink system as a
ground-based learning tool to correlate the picture out the window with the
weather depiction by that particular digital signal processing system.


Richard Kaplan, CFII

www.flyimc.com