Vacuum Cleaner Effect?

Sandia Peak, just outside Albuquerque, New Mexico is one of my favorite places to fly. Here are some pictures I took of the paraglider launch at Sandia.

The top photo shows David Prentice carefully checking the windsock at Tower 2 Ridge yesterday evening. The middle photo shows the launch and the reason for David's concern. The wind had been occasionally cycling from the north (from the right as you look at the picture) which sets up the VCE in the canyon in front of launch. The canyon is 1.5 miles wide and the hazards include the tram cables and the complete lack of landable terrain. The north wind creates overwhelming sink and turbs in the canyon. It's entirely possible to be 1,000 feet over the Peak and be suddenly flushed down into the canyon by a north cycle. That's why we prefer southerly days.

Last night here were a few north cycles and Davey waited until almost 6:30 pm, when the wind at Tower 2 had died off to nothing before he dared to launch into the still quite strong wind on top. The last photo shows Davey hoisting his AVAX RSF; he was plucked so quickly that I couldn't get a shot of the actual launch.

I rode the tram down and D had a smooth and perfectly uneventful sunset flight.