Aero-Terms are designed to be a daily reminder of the terms,
names, acronyms and explanations of the unique language that
populates the aviation world. Aerospace, sport aviation, fixed
wing, helo, you name it... it's all fair game.
Aero-Terms should serve as a quick but intriguing reminder of
the terms you may use every day, or an introduction to an aspects
of the Aero-World you may not yet be familiar with. ANN also
encourages readers to go beyond the FMI link, and further research
any intriguing terms.
A device normally located on uncontrolled airports and used as a
landing direction indicator. The small end of a tetrahedron points
in the direction of landing. At controlled airports, the
tetrahedron, if installed, should be disregarded because tower
instructions supersede the indicator.