Airfield Tetrahedron Design Information Request

[ProfromDover]

I remember discussing our prior tet with my dad while installing it. He was former USAAC/Airlines retiring with over 35K hours! He asked if it had a chain on the front for the tiedowns. I said what are those for? Its a wind indicator.

He said not so much. The tet and tee's are actually considered landing indicators and not wind indicators. I asked what's the difference? He said back in the day, based on the wind, the airfield folks would "set" the pattern by chaining the nose of the indicator to the favorable wind runway.

Again, remember that radio use was less common hence the gigormous size of the tets to be seen afar. Hence their extinction to the company of dodo birds and such.

In todays world we typically use the tets and such as a big honkin windsock. I have found the tet to be extremely sensitive and able to weathervane with even the slightest breath of a wind. And I have a fantastic recipe for dodo birds...

[Cvairwerks]

Bill: I can measure the one at Northwest Regional on Wednesday if you want. Glen mentioned today that they might be selling that one. Shape appears to be a 30-60-90 triangle with the hypotenuse parallel to the ground. He reminded me that if you build one, make sure you use a long enough counterbalance pole that you can adjust the balance as necessary.

[Obergrafeter]

Years and years ago while landing at Hondo, I checked the Tet and landed accordingly. I was all over the runway wondering what happened!! I looked at the windsock and it was a 180 degrees out with the Tet. A local told me the Tet had been rusted in that same position for years! I learned about flying from that for sure.