During my one in-air emergency (partial engine failure in a 172), I did
squawk 7700 as I called a radar facility, and it helped. The controller
then gave me a squawk code. There wasn't going to be any handoff, and I
think changing codes stopped alarms at his position and many others.

David

Mitty wrote:
On 2/23/2007 6:21 PM, Roy Smith wrote the following:

If you've already told the controller you have an emergency, squawking
7700 doesn't add anything to the situation. The 7700 stuff is for
when you're out of radio contact.

Au contraire. With a 7700 squawk then if the emergency situation wasn't
mentioned in the handoff (which it possibly wasn't) then the next
controller would still have known something was seriously wrong.

(Now possibly if AA had squawked 7700 he would have been asked to switch
off that code at some point, but we don't even know from the video
whether he tried it.)