Heaven forbid but I have to agree a little bit with DerSchtick. The aviation hand held's I've used were pretty range limited (ground to air) unless they were hooked up to a boosted external antenna. They worked better from air to ground than they did from ground to air.
The next problem we encounter with a ground based hand held is what frequency are we going to dial in to? For ground to air comms we need to know what the aircraft will be broadcasting on. Will they be talking to Tower or Approach? Will they have left Tower frequency for a CTAF frequency? Might they have changed over to an air to air frequency? Do we monitor the emergency frequency? We certainly can't be broadcasting on that one unless there's an emergency. Then again, once out of radio required airspace the pilot just might turn down the volume to make for a nicer flying experience. So we need a scanner to determine who's broadcasting on what but we don't know who is doing the broadcasting. Unless we can see their tail number it doesn't really matter that a conversation is initiated with identifying information. That helicopter you see and want to talk to might well be tail number N1234ZV when you are hearing a conversation started by someone identified with N14773 that's well out of sight.
So unless we are operating in an area that ATC has been notified of and provided a contact frequency for ATC to distribute to aircraft as an advisory, or a NOTAM was issued that listed your contact frequency, which needs to be a frequency approved for ground to air comms, you'll be rolling dice when trying to maintain situational awareness with a hand held radio. If, in the U.S., you're working so close to an airport that your altitude might be in conflict with full scale you really need to have been in contact with ATC long before flying there, and have provided all the info needed to the area FSDO to issue a NOTAM describing your location, altitude, and operating times. The NOTAM will not in any way reduce your responsibility to see and avoid. Hand held's are nice to have, but think about buying one real hard first.