Originally Posted by
Xeptu
"deliberately disabling the transponder"
It probably was deliberate but not intentionally deliberate. I had an emergency a few years back, which actually turned out to be two mutually exclusive events that came together at the same time which caused us "the entire crew" that we had a fuel leak. Without getting into the event, my first officer not only selected standby on the transponder prior to setting 7700 he didn't switch it back on either. I only noticed because the TCAS was off. A case of unintentional but deliberately disabled. How many of us in the heat of the moment would forget you dont need to select standby when changing codes.
No, it was not just put into standby. One of the reports mentioned that the mode it was put into was not a normal one, and would have taken some knowledge and several steps to achieve.