Question about Mode S Transponders.

[SkyWestCRJPilot]

I fly the 757/767 for Continental and we have been told in training that the air traffic controllers out of London can see what altitude we set in our MCP (Mode Control Panel for the autopilot and flight director) via the Mode S transponder. Is this correct or has someone at our company been fed false information? If there are specifically any London/UK air traffic controllers out there to answer this I'd be very grateful. Thanks.

 

[Piper877]

I know that's a feature of the NextGen ATC system in the U.S. I'm fairly certain it's simply a modification to the ATC computers that allow that sort of thing. It wouldn't surprise me if the U.K. already has it operating given how behind the U.S. is right now in Sat based stuff and such.

 

[ackattacker]

http://www.levelbust.com/articles/mode_s.htm

Enhanced Mode S enables the selective interrogation of aircraft plus the facility to down-link specific airborne parameters from the cockpit, such as Indicated Airspeed and Selected Altitude.

 

[patq1]

If your airplanes have enhanced mode S, these are the parameters that are downlinked:

Selected Altitude
Roll Angle
Track Angle Rate (or True Airspeed if Track Angle Rate is not available)
True Track Angle
Ground Speed
Magnetic Heading
Indicated Airspeed/Mach No.
Vertical Rate (Barometric rate of climb/descend or baro-inertial)

 

[Bumz_Rush]

and if you take sugar in your coffee

At least one of the London sectors/areas, has this facility.

It is not common yet, but soon they will see your alt preselect.

All to do with alt busts.

Very common in UK, with visitors from the other side.

bumz (a pilot)

 

[neflier]

It's part of 'Enhanced Surveillance', additional aircraft parameters that are broadcast over Mode-S. Here's a list of what is / can be transmitted:

Flight ID
Mag Heading
Ground Speed
Roll Angle
Track Angle Rate
True Track Angle
Mach No.
Indicated Airspeed
Vertical Rate
Selected Flight Level / Altitude

Pay special attention to the indicated airspeed. Now Big Brother will know when you exceed 250 below 10K. Can’t blame it on ‘instrument error’ or ‘tailwinds’ anymore.