If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
|
Thread Tools | Display Modes |
#11
|
|||
|
|||
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? |
#12
|
|||
|
|||
"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 |
#13
|
|||
|
|||
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? |
#14
|
|||
|
|||
"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 |
|
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Cuban Missle Crisis - Ron Knott | Greasy Rider© @invalid.com | Naval Aviation | 0 | June 2nd 05 09:14 PM |
Musings of a Commercial Helicopter Pilot | Badwater Bill | Home Built | 6 | February 27th 04 09:11 AM |
VW-1 C-121J landing with unlocked nose wheel | Mel Davidow LT USNR Ret | Military Aviation | 1 | January 19th 04 05:22 AM |
"I Want To FLY!"-(Youth) My store to raise funds for flying lessons | Curtl33 | General Aviation | 7 | January 9th 04 11:35 PM |
Off topic - Landing of a B-17 | Ghost | Home Built | 2 | October 28th 03 04:35 PM |