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Sobieski Tips |
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Sobieski Mountain, Skykomish WA Flying at Sobieski presents unique challenges for launching, flying and landing. To achieve any measure of consistent success you must maintain a heightened sense of awareness during all phases of your flight. We have had numerous incredible experiences at Sobieski. We have climbed to near 11,000 feet and flown deep into the Alpine Lakes Wilderness Area. The rewards can be spectacular. Landing at the airstrip can be accomplished successfully in a variety of conditions. We have found that the tall trees and the orientation of the strip sets up a classic wind shadow effect with a twist. Airspeed, airspeed and more airspeed are all key essentials to landing at Skykomish State Airport. A wind shadow is an extreme version of a wind gradient. During your descent into the narrow slot at Skykomish, the wind velocity found above the treetop level (i.e. 10-15) can drop to 0 at ground level. The twist mentioned above is a cruel tendency for the air to also dump into the slot from the south tree-line. As the evil twist meets the ground it can rise upward all along the length of the field. Zero headwind accompanied with the evil rising twist can make for an interesting landing. Note: The evil twist is a little more evil in a west wind. In a west, the twist can significantly yaw your glider on final. Successful landings in an east wind can be accomplished by gathering a ton of airspeed long before you descend to treetop level. Increase your speed to the prevailing wind velocity plus your normal approach speed (I try to add another 5 mph to account for the gust factor). If you think it's blowing 10-15 and your normal approach speed is 25 mph, you may want to turn final with 35-40 mph. With that scenario, if you enter at 40 and lose 15 due to the wind shadow effect you still have 25 to work with. Be prepared to have a long glide-out in ground effect in case the wind shadow is not as prevalent or in case the evil twist holds you up longer than expected. Successful landings in a west wind are even more interesting. Same scenario as described above except the wind shadow effect may not be as pronounced. The wind velocity seems to be a little more consistent as you near the ground; more of a wind gradient in my experience. The danger with the west wind conditions is that the velocities can be greater and the gust factor can be problematic for slow flying aircraft. My best suggestion for landing in a west wind would be to turn final well back in the field and well above the treetops. Carry as much airspeed as you dare down into the slot and be prepared to make immediate directional corrections all the way to the ground. Fortunately, Sobieski is primarily an east site so landing in a west wind is a less frequent occurrence (unless you're really brave and elect to fly the west facing side of Sobieski by launching off of the rock). As it happened last Saturday, it is not unheard of to have east winds at launch and west wind on the ground, so be aware. One important note concerning wind direction in the landing area. The existing windsock should not be trusted. That thing is so heavy that it takes a stiff breeze to swing it around. We always set up wind streamers to provide "light wind" indicators. Ref: wind shadow, wind gradient. Extreme caution should be exercised while flying at any mountain site. Unexpected wind effects, unexpected wind velocities and unexpected wind directions should be expected at any time. The Skykomish area is set in an area particularly vulnerable to the unexpected It is near the confluence of three significant river valleys. The Skykomish, Foss, and Beckler River valleys all meet in the immediate vicinity of the airstrip. I have heard of convergence conditions over that confluence that have made descent from altitude from difficult to near impossible. Given the increased attention to detail required, flying at Sobieski should be done only by pilots who possess advanced landing skills and previous mountain flying experience. The risk factor may be elevated slightly but the rewards can be great for those with the proper credentials. Are you interested in flying Sobieski Mystery Lift this fall? Airwreck.. |