| |
August 18, 2004. Cessna 172,Mountain flying
I take a lesson with Deane on mountain flying. First
thing he asks is: "Did you bring some extra clothes?". Here's
what I learned.
- Put your warm jacket over the back of your seat
so that it will be easy to put on should you be disabled in a crash.
- Tune the radio to the enroute airtraffic control
for the region you are flying in. When you are in the mountains you
may not be able to talk directly to the controllers but there are likely
to be jets overhead which will relay urgent messages.
- Think about the winds:
- Don't fly into the mountains when it is windy.
More than 15 knots at Boeing field, strong winds aloft, or large
pressure difference east and west of the mountains all indicate
strong mountain winds. Morning and evening are more likely to be
calm. Sunny afternoons are likely to be windy.
- Wind sinks on the windward side of a vally
and rises on the lewward side. In an east-west valley a north wind
will drop down the north side of the valley. Thus on one side you
will tend to sink and on the other rise.
- You can't really know what the wind will
be doing until you get there. Valley winds could be dominated by
winds aloft or up-down valley flow.
- Fly on one side of the valley so you have
space to turn around. There are several things to consider.
- Winds. Deane likes to fly on the sinking
wind side so that turns will be made into rising wind. Other people
like to fly on the rising wind side.
- Lighting. Deane likes to be in position such
that a 180 degree turn will be made toward well lit terrain.
- Terrain.
- Slow the airplane down to 75 or 80 and use 10-20
deg of flaps.
- A 180 degree turn can be executed in a tight
radius by applying power and making a steep turn. Slowing the airplane,
full flaps, and full power will make an even tighter turn.
- Approach ridge crossings at 45 degrees. This
will make it easier to turn away from the ridge should you decide to
not cross it.
- Be very cautious about flying into rising terrain.
Be sure that you have an escape - some way you can turn to open terrain
and safe flying.
As for landings:
- Valleys are often to narrow for standard patterns.
Figure out the best approach.
- Fly over runways to inspect landing area and
scare off wild life. Consider doing this as a low pass practice for
landing.
- Know what your go-around options are. Some strips
have rising terrain in one direction which makes a go-around impossible.
- Abort any landing that does not feel right.
- Be very alert for wind sheer and turbulance as
you approach the trees.
<<Prev
| Next>>
|