In article
,
a wrote:

I would have expected the burble that causes the waves had to be
within a couple of thousand feet of the ridge altitude, but you got
rides to much higher than the mountains in WV -- ridge altitude plus
what -- 5 or 6000 feet? Neat stuff. You get to play in what we could
call 'fly through/over' conditions. I guess wave height has also a
lot to do with the ridge to valley distance on the upwind side.

Wave height is mainly related to the atmospheric temperature and wind
profile. I won't claim to understand how it works, but there's not a big
relationship between the mountain height and the wave height. Basically,
when wave is good, each layer of the atmosphere ends up perturbing the
layer above it in the same fashion, causing the wave to just go up and
up. I was up at 10,000ft this past June in wave, and that was about as
high as I was able to take it, but I could see obvious wave clouds at
what looked like 20-30,000ft. I know people who have been to well over
20,000ft in this area, including this fascinating and somewhat
frightening story that I was lucky enough to first hear in person from
that pilot:

http://wave99.info/info/article:the_price_of_a_jewel

The previous world altitude record in gliders was set in northwestern
Nevada, and achieved, I think, 49,000ft. The current record is 50,699ft,
set in the Andes. The Perlan Project (http://www.perlanproject.com/) is
currently constructing a pressurized glider that they hope will take
them to 90,000ft in Andes wave, and they believe that it goes higher
still.

My phone's navigational ability is limited to indicate "this way is
down" or at least "the local acceleration vector is pointing this
way". A ring tone that sounds like the middle marker might be fun:
"Answer or I'll announce the miss!" An ex marine I'm friendly with
somehow has programmed his cell phone to use a voice to announce a
call, but I think at Fort Bragg and elsewhere having a phone say
"Incoming!" would not be a good idea.

I have an iPhone, which has a built-in GPS. A couple of days before the
flight I decided that it would be good to be able to use it in flight,
so I wrote a little web app (which can be stored to the phone, since
there's usually no cell signal in flight) which takes the GPS output and
dumps it to the screen, plus some useful derived information like
distance and bearing to my home field.

Once I tested it in flight I discovered two bugs where I had screwed up
the unit conversions, causing my altitude readout to be off by about a
factor of 10 (showed 800ft when we were at 8,000ft) and my groundspeed
readout to be off by a factor of 4, but it was still handy, particularly
the "distance to home field" which I used quite a bit (with sanity
checks against the chart and local terrain... I don't trust my own
programming that much, especially after seeing those other errors) to
decide whether to press on deeper into the system.

--
Mike Ash
Radio Free Earth
Broadcasting from our climate-controlled studios deep inside the Moon