On the subject of being asked by ATC to squawk 7700:
Originally Posted by
gearlever
Really?
Who is in charge of the airplane?
I'm getting old....
ATC controllers often work from filtered screens, meaning that certain aircraft not in their sector, (e.g, above or below), will be invisible to them.
By squawking 7700, the system causes an aircraft to become visible on all screens, including filtered ones, so that all controllers will see an aircraft that might be vectoring in an unusual or non standard direction, and possibly about to come back into their sector. This improves controller situational awareness, and alerts Approach, Tower and Ground controllers etc, to see the affected aircraft and make allowances for its routing and probable return to land.
I can thoroughly recommend that pilots visit ATC on one of their TRUCE days. It is a fascinating and really worthwhile day out.
