TetraDirect Wind Drift Indicators Presents the "TETRAHEDRON" The Tetrahedron is a four sided polygon, ...or a highly sensitive wind indicator. The Tetrahedron TetraDirect proudly presents a new way for skydivers and pilots to see the wind direction while landing. The Tetrahedron. The Tetrahedron is a highly visible wind indicator. Observable from as high as 3000', it is an invaluable aid to landing for both skydivers and pilots. Knowing the wind direction is key to a safe landing. Early detection is what the Tetrahedron affords. Already in use on many dropzones and airports, this device has proven effective in all landing conditions. Please check out these pages for information on how it works and how to get one.