Narrative:

A C750 [was] en route at FL470. The C750 keyed up on frequency with a request during a period of frequency congestion. I answered 1 or 2 other aircraft and then responded to the C750. The C750 calmly requested a descent to FL430 and did not indicate any distress. After being cleared to descend to FL430; the aircraft was handed off and shipped to the next sector. The aircraft's beacon code was indicating an emergency a couple of minutes later and was unresponsive to transmitters from my frequency and descending rapidly. It was determined after the aircraft's safe landing along with rapid depressurization; the aircraft had deteriorated transmission capability. The tower reported having difficulty hearing the aircraft while it was in the pattern. A timely report from pilots regarding equipment malfunctions.

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Original NASA ASRS Text

Title: Enroute Controller noted the rapid descent of an aircraft squawking emergency. The reporter noted pilots should be more forth coming with information to ATC as to their status.

Narrative: A C750 [was] en route at FL470. The C750 keyed up on frequency with a request during a period of frequency congestion. I answered 1 or 2 other aircraft and then responded to the C750. The C750 calmly requested a descent to FL430 and did not indicate any distress. After being cleared to descend to FL430; the aircraft was handed off and shipped to the next sector. The aircraft's beacon code was indicating an emergency a couple of minutes later and was unresponsive to transmitters from my frequency and descending rapidly. It was determined after the aircraft's safe landing along with rapid depressurization; the aircraft had deteriorated transmission capability. The Tower reported having difficulty hearing the aircraft while it was in the pattern. A timely report from pilots regarding equipment malfunctions.

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.