Narrative:

Aircraft X was in a descent to FL220 and turned 10 degrees right for departure traffic coming out the departure gate. I advised aircraft X that there would be a delay at FL220 for enroute traffic. While in the descent; aircraft X declared an emergency and requested lower. I advised aircraft X that I could not give a clearance for lower because of a king air. Position of the king air was approximately 2 to 3 miles southeast of aircraft X. I asked aircraft X to verify he had declared an emergency because the radios where not very clear. He affirmed; I then called traffic to aircraft X (the king air) and advise when leaving FL200; aircraft X relayed that they were already out of FL190.

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Original NASA ASRS Text

Title: Enroute Controller described a loss of separation event when a military aircraft with an emergency descended prior to receiving ATC clearance.

Narrative: Aircraft X was in a descent to FL220 and turned 10 degrees right for departure traffic coming out the departure gate. I advised aircraft X that there would be a delay at FL220 for enroute traffic. While in the descent; aircraft X declared an emergency and requested lower. I advised aircraft X that I could not give a clearance for lower because of a King Air. Position of the King Air was approximately 2 to 3 miles southeast of aircraft X. I asked aircraft X to verify he had declared an emergency because the radios where not very clear. He affirmed; I then called traffic to aircraft X (the King Air) and advise when leaving FL200; aircraft X relayed that they were already out of FL190.

Data retrieved from NASA's ASRS site as of July 2013 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.