Dick: I may be misled, but I know the full scale pilots I hang with agree with Thornburg. The thermals(bubble/column of warmer/wetter air from the generator - dark wet field) break loose and go up in altitude to the due point, (higher alltitude lower pressure and lower temp) at which point a cloud appears. The clouds form a "cloud STREET!" A straight line of alternating "cloud, clear air, cloud," etc - thus it looks like a STREET of clouds. Assuming a constant wind vector. The alternating clear air and cloud is cause by the loss of energy from the generator as it heats up the present column of air - after a while the generator has stored enough energy to once again heat a sizable column of air. I was told like drops from a spigot "only falling up." jim ealy
Dick Williamson wrote: > John, > > Full-scale soaring pilots describe a phenomenon called "cloud > streaks" or something similar. The observation is that lines of > cumulus clouds will sometimes form into streaks with clear air > between the cloud streaks. The streaks generally run parallel to the > wind. The pilots have observed that there is good lift underneath > the cloud streaks and sink in the clear air between the streaks. A > cloud streak indicates a long sustained corridor of lift. The > situation is very different from Thornburg's "river of air" in which > one envisions separated thermals drifting downwind with the > prevailing wind. > > Dick > > ======================== > > >Hello All! > > > >Wednesday I took a really long lunch to go flying with > >another RCSE member who was in town. Every time I get > >to fly with someone I get to learn new things and see > >some neat flying to boot. > > > >For the new things, this fellow worked with me to > >learn more about triming out planes, and when we were > >done, my little 15oz HLG lost some weight and floated > >far better than previously. It was once a really fast > >bullet, and now it looks a whole lot "floatier" and I > >found it easier to keep up. > > > >Now for the subject - River of lift. There were good > >thermals, especially at the altitudes he launched his > >open class plane. Many times he skyed out, but his > >last flight was quite memorable for me. It started out > >after the highstart launch with him finding a little > >bubble of lift that he kept riding, without gaining > >much altitude, for quite a ways down wind. Then all of > >a sudden that little bubble zoomed! He started > >climbing at a very rapid rate until he was specked out > >a long ways up and a long ways down wind. Then, to my > >surprise, he started working his way back upwind, > >thermal turning the whole way and maintaining > >altitude. After a while he was as far upwind, at speck > >altitude, as he had been downwind. > > > >I asked how he did that and he said he had found a > >"river of lift" that he rode upwind. I didn't mention > >it, but I noticed that over the lift where he had > >flown there was a distinct stream-shaped cloud > >formation. I was wondering afterwards if seeing > >another stream of clouds like that would be a place to > >find another river of lift. Something to try someday > >when I step up to a big glider. > > > >There is so much joy is seeing our planes stay up on > >nothing but heat energy. > > > >John Gossett. > > > >===== > >John Gossett, Austin Texas > >RC Soaring Site: > >http://www.geocities.com/johntestsgo/index.html > > > >__________________________________________________ > >Do You Yahoo!? > >Yahoo! Greetings - Send FREE e-cards for every occasion! > >http://greetings.yahoo.com > >RCSE-List facilities provided by Model Airplane News. Send > >"subscribe" and "unsubscribe" requests to [EMAIL PROTECTED] > > -- > - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - > Dr. Richard C. Williamson Phone: 781-981-7857 > Room C-317 FAX: 781-981-0122 > Lincoln Laboratory Email: [EMAIL PROTECTED] > Massachusetts Institute of Technology > 244 Wood Street > Lexington, MA 02420-9108 > - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - > RCSE-List facilities provided by Model Airplane News. Send "subscribe" and >"unsubscribe" requests to [EMAIL PROTECTED] RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]
