Cone of confusion

saracelica

saracelica

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saracelica
Flying a VOR approach and at some point I asked "Why is the VOR doing that?" the CFII said "Ah you are in the *cone of confusion*" He meant to talk about it during debrief but we were both short on time. Anyone help me out?
 
When you get sufficiently close to the station your receiver can't really tell what radial you are on, hence the confusion. If you are passing over (close) the station you will know you have station passage by the To/From flag flipping.
 
Yeah just like a radar antenna, there's a spot directly above it where you're not being "painted." I was giving a little Skipper FF once when he flew over the radar "main bang" and changed his course. When he popped back up on radar he was pointed right at a Bonanza. One of the few times I had to use "traffic alert!"
 
What they said. That's why you turn over the VOR to a heading you think will keep the needle centered. In a couple of seconds, you see that you're lose to tracking he radial outbound. So fly the heading and be patient.
 
The cone of confusion is what happens when you try to fly into midway in a slow plane during the morning rush. Everything after "cross kankakee at..." is very confusing. As a gamble you can speak with a southern drawl, it may get you slower instructions or it may get you sent on a tour of lake michigan.
 
cone_of_silence12.jpg
 
Jaybird180 said:
Ron- What is the depiction?
Click to expand...

Well it's actually the Cone of Silence (from Get Smart).
The real cone of silence (rather than zone of confusion with VOR) comes from flying over an old AN station.

f0169-03.gif
 
saracelica said:
Flying a VOR approach and at some point I asked "Why is the VOR doing that?" the CFII said "Ah you are in the *cone of confusion*" He meant to talk about it during debrief but we were both short on time. Anyone help me out?
Click to expand...
The NAV receiver derives azimuth information from detecting the phase angle between two signals, one of which is transmitted at different phase angles in the horizontal plane. If you are directly above the station, the receiver cannot adequately determine the phase relationship between the isotropic and anisotropic signals.

TACAN generally has a bigger cone of confusion, which is why station passage is determined by using the DME switch and not the "CDI flip."
 
just for fun....When I used to teach..I would suddenly act all confused crossing a VOR station and insist we were lost..as soon as the VOR came back I would drop the act just as fast.

the "old school" method (which is a little long from my observation) is 1/2 your altitude is where you can expect this unreliability/hyper-sensitivity...ie 5000 is 2.5 total cone circumference ...makes some VOR approaches a PITA, you will learn to love GPS
 
Not for nuthin Sara, but how did you not learn about that during your private?
 
For another data point... turn on the Nav audio when directly over the top of the VOR and the "cone of confusion" will become much clearer... 'cause you'll often actually hear the crappy signal being received right at that point in space. :)

(Crap, I just realized there's a whole generation growing up right now who've never heard static through any of their "radio" devices.)
 
Captain said:
Not for nuthin Sara, but how did you not learn about that during your private?
Click to expand...

I probably *did* know it but it came up and I figured others may wonder what it was as well.
 
saracelica said:
I probably *did* know it but it came up and I figured others may wonder what it was as well.
Click to expand...


A common problem I run into is pilots who think 'if I can just memorize enough stuff I'l be a great pilot!'

But that's not how it works. It's not facts and data that make a great pilot...it's understanding. You can sit there and memorize that there is a 'zone of confusion' over a VOR or any directional antenna like RADAR...but to zen into the moment you should look at how the VOR works.

Look at how it transmits. Look at the Lobes sent out. Notice those lobes don't go straight up and realize if the lobe doesn't go straight up then there must be an area above the thing where I won't receive it. Dig further and realize it's got a name. The 'cone of confusion'. It's obvious really if you think about it. Something that should stick if explained right...

So...going forward, if you don't get something do what you did. Post here or find out another way. I'm not lecturing you. I think you did good here. Now I just want to talk to you primary CFI.

(J/K)
 
flyingron said:
Well it's actually the Cone of Silence (from Get Smart).
The real cone of silence (rather than zone of confusion with VOR) comes from flying over an old AN station.

f0169-03.gif
Click to expand...
Ron is correct about this one.
 
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