Setting altimeters with no radio

agreed
"Neil Gould" wrote in message
m...
| Recently, Mxsmanic posted:
|
| "Jim Macklin"
writes:
|
| GPS, even a $100 hikers model will solve the problem.
But I
| just say, look at the ground, you can judge 1,000 feet
| pretty well and you only need to apply the hemisphere
rule
| above 3,000 AGL.
|
| GPS is far less accurate than an altimeter, and I don't
think the
| regulations say "if you have no radio, use GPS."
|
| I'm not sure why you think that "GPS is far less accurate
than an
| altimiter...", as an altimeter only need be accurate to
75' to be legal.
| GPS can do much better than that, and are unaffected by
barometric
| pressure; the result is a potential source of problems
that require pilots
| to fly by the altimeter, not the GPS. None of this has
anything to do
| with regulations, of course.
|
| To answer your original question, the prudent pilot will
take the
| barometric pressure of their destination into
consideration during
| preflight planning, and adjust the altimeter accordingly.
Most of the
| time, the pressure won't change all that drastically at
the destination in
| the time it takes to fly 100 miles, and non-radio VFR
pilots aren't likely
| to fly in weather where the pressure is changing too
rapidly.
|
| Neil
|
|
|