Segmented Circle

[Joe Pires]

I am studying for the sport pilot test. For the life of me I can not understand the explanation given for the segmented circle.

What I have been able to determine is that the wind cone is a wind sock so in the example above the wind is from the north west. What I can not fathom is what the L or 7 shaped lines are trying to tell me. It seems to indicate they are giving me information on which way the pattern runs but It just is not clicking with me. Any patient bored people around who might help?

 

[iconnary]

Joe, you are correct in that they indicate the direction of the traffic pattern for each runway. Think of each right angle indicating the direction you would make your crosswind turn if you were departing in that direction.

With the wind given in the example you would use either the west runway and make right traffic, or use the north runway and make left traffic.

 

[Gary_in_Orygun]

This situation could have a pilot departing or landing on the N/S runway (36) (with 45 degree crosswind from the left) in which he should use a left-turn traffic pattern.

If a pilot took off or is landing from/on the E/W runway (27) (with a 45 degree crosswind from the right) he should use a right-turn traffic pattern.

 

[Joe Pires]

Thanks to both of you, for some reason this did not click before. I get it now.

 

[Harry_S.]

I am studying for the sport pilot test. For the life of me I can not understand the explanation given for the segmented circle.

What I have been able to determine is that the wind cone is a wind sock so in the example above the wind is from the north west. What I can not fathom is what the L or 7 shaped lines are trying to tell me. It seems to indicate they are giving me information on which way the pattern runs but It just is not clicking with me. Any patient bored people around who might help?

I would take that *windcone* as a tetrahedron indicating wind from the southeast.

If that is the case...I would use for T/O either 18 or Niner. If I used 18 it signifies R/H traffic. If I used Niner, it signifies L/H traffic.


Cheers

 

[iconnary]

Harry I think you're correct. At a glance I took it to be a windsock.

 

[Joe Pires]

The text indicated wind cone was another name for windsock and I also found the following.

Noun 1. wind cone - a truncated cloth cone mounted on a mast; used (e.g., at airports) to show the direction of the wind
air sock, wind sleeve, windsock, drogue, sock
visual signal - a signal that involves visual communication

 

[Harry_S.]

The text indicated wind cone was another name for windsock and I also found the following.

Noun 1. wind cone - a truncated cloth cone mounted on a mast; used (e.g., at airports) to show the direction of the wind
air sock, wind sleeve, windsock, drogue, sock
visual signal - a signal that involves visual communication

Well you have to go along with what that educated AH put in the question.

Back when common sense was in vogue...field wind indicators were either a *windsock* or a *tetrahedron.* In the example above, the symbol used and the printed word were in conflict IMHO.

I've not seen a windsock shown with a pointed tail.


Cheers

 

[scottessex]

That is one of those questions that you have to pick the "most correct" answer.

 

[GyroChuck]

Wind tee or wind sock I can't tell. The purpose of the traffic pattern is to have aircraft avoid houses or town to the southeast. Most likely for noise avoidance.

 

[PW_Plack]

Harry,

A tetrahedron, like a windsock, indicates landing direction like an arrowhead, pointing with its small end. In the diagram, a tetrahedron would also be indicating a NW wind.

Some tetrahedrons are moved by the wind like a weathervane, but some can be turned by an electric motor under remote control to indicate a specific runway. For this reason, a tetrahedron is not a reliable indication of wind direction. (Although in the diagram above, the indicator obviously isn't being positioned arbitrarily, since it's not aligned with one of the runways.)

 

[Harry_S.]

Harry,

A tetrahedron, like a windsock, indicates landing direction like an arrowhead, pointing with its small end. In the diagram, a tetrahedron would also be indicating a NW wind.

Paul,

I had to reread the above several times till I finally got what you intended.

I've still got a problem of taking that *arrowhead* as a symbol for a windsock. I've not seen it before. I took it as indicating a tetrahedron and a SE wind.

Most all segmented circles I've seen in past years had a tetrahedron in the center of the circle and a windsock somewhere *outside* the circle, to indicate wind direction and approximate "windspeed."

Most oldtime tet's were in the form of a TEE with a vertcal fin at the the tail of the long leg.

Now, I see a lot of 'em made to resemble an AC cabin with a pointed nose and twin verticals. At my airport, we have L/H traffic, a tetrahedron off the runway intersection and THREE windsocks. Hardly ever do two of the socks have the same indication.


Cheers

 

[Rotornut]

Got my Windsock, just wish Richard would put it up! MJ

 

[PW_Plack]

Harry, I think we saw the same thing in our heads, just said it differently. A tee indicator with a fin on the long leg also points its crossbar (wide end) into the oncoming wind, like a tet or sock.

MJ, isn't a wind sock something you keep at chapter meetings, so when someone gets long-winded, you can tell him to stuff a sock in it?

 

[Rotornut]

LOL @ Paul. MJ

 

[JRB549]

By the way Wauchula finally got it's mid-field new wind sock!

 

[Harry_S.]

Harry, I think we saw the same thing in our heads, just said it differently. A tee indicator with a fin on the long leg also points its crossbar (wide end) into the oncoming wind, like a tet or sock.

That's right Paul and the old instructor would tell the student pilot...the tet down there is like a model airplane that is landing into the wind and that crossbar at the front of the tet, is the wings on *your* airplane and that indicates the appropriate runway you will use to *attempt* your landing.


Cheers

 

[Rotornut]

Thanks for telling us JR it's about time. Glad they got it up. MJ