The Windward Performance Perlan 2 is an American mid-wing, two-seats-in-tandem, pressurized, experimental research glider that was designed by Greg Cole and built by Windward Performance for the Perla
Perlan 2 on display with an Airbus A350 XWB for scale in background
Perlan II in the air
Lee Waves
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In meteorology, lee waves are atmospheric stationary waves. The most common form is mountain waves, which are atmospheric internal gravity waves. These were discovered in 1933 by two German glider pil
A Moazagotl lenticular cloud
A fluid dynamics lab experiment illustrates flow past a mountain-shaped obstacle. Downstream wave crests radiate upwards with their group velocity pointing about 45° from horizontal. A downslope jet can be seen in the lee of the mountain, an area of lower pressure, enhanced turbulence, and periodic vertical displacement of fluid parcels. Vertical dye lines indicate effects are also felt upstream of the mountain, an area of higher pressure.
A wave window over the Bald Eagle Valley of central Pennsylvania as seen from a glider looking north. The wind flow is from upper left to lower right. The Allegheny Front is under the left edge of the window, the rising air is at the right edge, and the distance between them is 3–4 km.
Hydrostatic wave (schematic drawing)