Was Flying out of Niagara Falls(IAG) to JHW in a Navajo and overheard RPA3489 Request a return back to the airport. The controllers asked if they needed assistance and they replied per there checklist it instructed them to land at the nearest suitable field. After they were vectored around they declared an Emergency just outside the marker for the ILS 5. 70 on board(i think) 8500lbs of fuel. Apparently there FWD Cargo Fire Suppression test had failed and they wanted to be on the safe side by declaring an Emergency.
PermaLink on FA
http://flightaware.com/live/flight/RPA3489/history/20091009/2135Z/KBUF/KDCA
LiveATC.net Feed (about 2/3 through)
http://archive-server.liveatc.net/kbuf/KBUF-Oct-09-2009-2130Z.mp3
Zach