First helicopter landing on Mt Everest

Did you see the video shot from the A-Star's belly? If this is genuine (and
I have no reason to think it's faked), the pilot made a more or less
horizontal approach to the peak -- he did not descend from a ridge-lift
situation. The summit was a blunt arrowhead of hard, windblasted snow --
the rotor wash didn't move the surface snow around at all. There was no
level ground, no way to get both skids onto the snow at once. No ground
effect there because of the way the terrain falls off in all directions.
The machine hovered for two minutes, repeatedly pressing one skid into the
hard snow and leaving an impression. Then the collective came back, the
machine rose a foot or two, torqued around and dove for the valley.

I call it a landing. It was close enough that a ballsy climber could have
flopped into the machine for a ride home.

Seth
Comanche N8100R

"Skywise" wrote in message
...
Chris Colohan wrote in
:

"Peter Duniho" writes:

I'm surprised there hasn't been any mention of this yet. IMHO, this
isn't getting nearly enough attention (here or in the media in
general).

http://www.mounteverest.net/story/Fr...persUtopiasumm
it-VIDEOMay272005.shtml

Did it land, or didn't it? Apparently there is some controversy:

http://www.kantipuronline.com/kolnews.php?&nid=41844

Chris

Unless I misread the article, it seems that the issue is if
they had permission to land on the summit. Since they weren't
explicetly given permission to land on the summit, the attempt
doesn't count towards the record.

Kinda reminds me of the flap over the world land speed record.
Who broke mach 1 first? ThrustSST in 1997 or the Budweiser
rocket car in 1979? It's controversial to this day.

Well, I'm still damned impressed anyway, on both events.

Brian
--
http://www.skywise711.com - Lasers, Seismology, Astronomy, Skepticism

Home of the Seismic FAQ
http://www.skywise711.com/SeismicFAQ/SeismicFAQ.html

Sed quis custodiet ipsos Custodes?

"Mike Rapoport" wrote in message
k.net...
I don't think that wave lift is described as orthographic.

That's "orographic".

Wave is a gravity/compression phenomonon and ridge lift is just wind being
forced up hill.

Wave only happens as a result of orographic lifting. IMHO, the fact that
some of it occurs downwind of the hill is irrelevant to the fact that it's
part and parcel of the whole effect of the hill. The ridge lift is simply
the first bump in the whole wave.

Another distinction is that wave lift at mountaintop level is several
miles downwind of the mountain and ridge lift is upwind and immediately
adjacent to the lifting surface.

The wave lift downstream of the hill is just a single component of an entire
phenomenon. It's just an updraft portion of a complete wave system, a
system that starts upwind of the hill.

Pete

In article ,
"Peter Duniho" wrote:


The wave lift downstream of the hill is just a single component of an entire
phenomenon. It's just an updraft portion of a complete wave system, a
system that starts upwind of the hill.

Pete

Is this to say that in this wave system the air motion, at least at
certain altitude levels, has vertical velocity components that oscillate
between positive and negative values with increasing downwind distance?
-- maybe with something like a highly damped sinusoidal variation if
plotted vs downwind distance?

Even with my feeble to nonexistent knowledge of fluid mechanics and
aerodynamics I can picture that.

If so, what's the approximate horizontal period of the oscillation?
Would it happen also with a thin vertical wall?

"Peter Duniho" wrote in message
...
"Mike Rapoport" wrote in message
k.net...
Wave is a gravity/compression phenomonon and ridge lift is just wind
being forced up hill.

Wave only happens as a result of orographic lifting. IMHO, the fact that
some of it occurs downwind of the hill is irrelevant to the fact that it's
part and parcel of the whole effect of the hill. The ridge lift is simply
the first bump in the whole wave.

Another distinction is that wave lift at mountaintop level is several
miles downwind of the mountain and ridge lift is upwind and immediately
adjacent to the lifting surface.

The wave lift downstream of the hill is just a single component of an
entire phenomenon. It's just an updraft portion of a complete wave
system, a system that starts upwind of the hill.

Pete


I don't want to beat this to death but no glider pilot in the world would
equate ridge lift with a mountain wave system. Ridge lift occurs any time
that wind blows over rising terrain and it does not extend much obove the
ridge top. A mountain wave system is a function of numerous variables
including increasing wind speed with alititude, angle between the direction
of the wind and the ridge. It requires stable air. The correct term is
actually gravity lee wave and it all starts *after* the obstacle.

So yes, you need wind blowing up hill to produce a gravity wave but the wave
itself is down wind of the ridge.


Mike
MU-2