I'm with FireFlyBob on this one.
Even pressing clear (twice) on the transponder fitted to the A320 series aircraft won't actually clear the transponder code (although it does visually). Only when the new 4 digit code is entered will the actual code being squawked be replaced.
As buttons are used to enter the code, I think you'd have to try very hard to put in an emergency code. More relevant to the days of physically dialling it up I reckon.
My airline gives no guidance on this. I NEVER turn it to sby and so far, I've never been picked it for it by any trainer or picky line-captain either. Something else to consider too (my understanding anyway).... Based on the squawk the ATC guys have a number of other entries such as callsign, departure and arrival airport etc. If putting to standby (effectively stopping the transponder squawking anything) will this information 'tag' be lost? Perhaps some Air Traffickers would care to comment on the merits (or not) of this?
Personally, I think there's far more to get excited about. Like Kylie for example. She's worth getting excited about!
LOC
