chipsoars wrote:
On Mar 4, 4:37 pm, "Peter" wrote:
What is the maximum altitude (about) when the mobile phone becomes
useless? PeterK

It varies enormously in the USA. My experience is the closer I get to a
big city, the lower I have to be to get a signal, maybe 3000' agl. In
the country, I've used it at 15,000' agl during wave flights. My
explanation is the smaller cells and lower powers used in areas with a
lot of people just don't reach upwards very high.

I've had it ring at 2500'agl at which point I told whoever (my wife
and curtly too) that I was busy flying and then shut it off (I forgot
to shut it off prior to launch). If many consider it unsafe to
drive and talk,

Driving requires constant attention because obstacles are so close to
you, like oncoming traffic and the ditch beside the road. This isn't
true for most glider flying. So, it's easier to do safely.

why do it in the air?

I usually do it because I can't reach my crew on the radio; e.g., my
radio or theirs has failed, I am too far away, or there's a mountain in
the way. Recently, our local ASOS was off the air but it still reported
over it's phone number - most pilots dialed it up when they were inbound
for a landing.

I don't suggest using it to chit-chat, or when you need to concentrate
on flying the glider, but if it will significantly improve your safety,
it seems like a good use of the phone.

--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly
* "Transponders in Sailplanes" http://tinyurl.com/y739x4
* "A Guide to Self-launching Sailplane Operation" at www.motorglider.org