You can identify them by first purchasing a radio frequency scanner
specifically designed to cover common VHF frequencies, such as at
Sporty's Pilot Shop:
http://www.sportys.com/acb/showdetl.cfm?DID=19&Product_ID=6679&CATID=165
Find some terminal area and en route navigational charts which list
the local frequencies in your specific air space sector, and program
those frequencies into your scanner. In the US, I'd listen to either
Approach Control for a specific airport, or ARTCC (call sign "cityxx
Center") for aircraft just passing through. I'm sure the situation
would be similar in Ireland - Dublin Approach Control, etc.
Basically, listen for planes checking in and out with the air traffic
controllers covering your air space which will generally be in the
format of "AIR TRAFFIC CONTROLLER CALL SIGN, THIS IS (Airline) FLT #,
ALTITUDE" plus maybe other info such as destination, direction,
requests etc.
Try to do this when planes are flying over head, and note their
general direction and approximate altitude to see if you can
positively correlate a particular aircraft with the transmission you
are hearing. A plane heading "One-eight-zero" i.e. 180 or south, would
not correlate with a plane obviously heading eastbound, but one
heading "zero-eight-zero" would. Also, a strong "loud-and-clear"
transmission when there is an airliner directly over head would be a
good indicator that the pilot you hear talking is flying the aircraft
you can see. Keep in mind, pilots can go many minutes without talking
on the radios, so you won't always hear a transmission just because
you can see the aircraft.
Once you have picked up an aircraft's call sign (usually the airline
and flight number, example "United 227") it's relatively easy to
figure out it's origin and destination. Go to the airline's web page
and look for the Check Flight Status tool, and enter the flight
number. Make sure the flight number you find correlates to the date
and time you picked up the transmission, and see if it jives with the
aircraft being 20 miles outside of Dublin per the flight plan.
I'm assuming you're not a Terrorist or anything, and would use the
information for curiosity rather than malevolent purposes, which if
that's the case diregard everything I've told you. |