"Grumman-581" wrote in message
...
On Thu, 16 Nov 2006 20:13:14 -0700, Newps wrote:
As long as you clear them it doesn't matter how high. Safety depends on
the weather. I have skimmed over and thru the mountains at 50-100 agl
on nice calm days.

I prefer a bit more air underneath me than that considering the anemic
climb rate of my aircraft at altitude... When I flew to the Grand Canyon a
few years back, I encountered 2000 fpm updrafts... That was *great*... I
talked with some of the charter pilots around there about it and soon
learned that you can also encounter 2000 fpm downdrafts... That would
*not* be great...



I have indeed encountered both updrafts and downdrafts at rates greater than
2000 fpm and at altitudes over 10,000 feet msl. Most GA piston aircraft do
not have a great deal of reserve at those altitudes. As a result you can
not "brute force" your way through the mountains, particularly in Colorado.
I remember many years ago now, a Convair with a football team aboard flew
into a canyon west of Denver. As soon as my buddy saw them fly into the
canyon he called out the rescue squad and we started up the canyon to pick
them up. At the altitude they entered the canyon there was no way they
could continue to outclimb the canyon floor and it was not wide enough for
that airplane to execute a 180 degree turn. Sure enough, the canyon climbed
up and caught them.

Flying in the mountains requires a lot of knowledge about terrain, weather,
winds, and your airplane. It is a skill similiar to flying cross country in
a sailplane. I had an engine quit on me one time west of Denver in a
Taylorcraft L2. I caught a wave and flew for almost an hour with the prop
stopped! With no electrical system and a wooden prop on a fresh overhaul I
dove at Vne and couldn't get it to windmill! No restart likely. Landed
finally at Columbine Airport in Englewood.

Highflyer
Highflight Aviation Services
Pinckneyville Airport ( PJY )