Changing Heads?

[TD&H]

Putting aside visions of Wurzle Gummidge...

The other day on a transponder check the ATC said he couldn't see my squawk, but then he said he would change his head and lo and behold I could be seen.

What did he do, what are the implications for my transponder, my aeroplane being seen on radar?

I am waiting to get an avionics guy look at my unit, but in the meantime I would appreciate your comments and explanation of what is meant by changing heads.

Thanks H

[benedictus]

He will have changed the source radar on his display, thereby getting a picture from a different radar head, hence "changing heads"

[Cuddles]

He probably had to change which radar source he was using, as you weren't within the coverage of the one he was using at the time.

As they got you identified, I'm fairly sure you're equipment wasn't at fault.

Cheers

[TD&H]

Thanks for the replies.

Regarding the coverage of the radar source he was using, at a similar position in the business jet I fly (albeit at a greater height 4000-5000 against 2500-3000 and with mode s)we get picked up immeadiately. Thats why I chose that particular ATC unit and location for the test.

Also I had given my actual location and height (no mode C), so wouldn't it have been natural for the controller to use the appropriate head? :confused: :ok:

[AlanM]

Was it on 132.7 - were you NE of Brentwood??! (at 3.4A)

If that was you, then I had to change from the H23 (Heathrow 23cm radar at Heathrow of course) to the Debden (North of Stansted)

I had just swapped to the H23 as I was given a RIS to intermittent traffic at OCK going west lowish. The radar gets affected by the weather (high pressure over the Uk at the time of 1032mb)

Some controllers do have two faces though.....! :)

[Jerricho]

And one eye........ain't that right Al :p

[AlanM]

Not totally sure of what theat means.... but yes, I s'pose!