Wirelessly posted (Opera/9.80 (BREW; Opera Mini/6.0.3/27.2354; U; en) Presto/2.8.119 320X240 LG VN530)
IIRC, at least one of the helo's is dual-marked. On one side it says Phoenix Police Department, and on the other side it says Phoenix Fire Department.
When on Phoenix PD talkgroups, they ID as "Air nn", where nn is the time it goes off duty. (Air 12 goes off duty at 1200 hours. Air 24 goes off duty at midnight. Etc) When talking to Phoenix FD or any other agency, they ID as Firebird, and the number is based on the tail number.
You should add 123.025 and 123.550 to your scanner. 123.025 is used by all helos to announce their movement to all other helo traffic. 123.550 is the Phoenix PD "company" channel. Phoenix PD pilots use it for extended conversations so as to not tie up 123.025 when there are 2 helos up at the same time.
I've also recently heard 2 pilots take a conversation to A-12, one of their encrypted talkgroups.