Narrative:

Shortly after switching to washington's final approach controller, an aircraft began broadcasting on the frequency with a stuck microphone. The aircrew maintained a steady stream of conversation not pertinent to their flying duties and effectively jamming the frequency while we were awaiting further vectors for sequencing into washington national during the afternoon rush. Fortunately, the alert controller managed to announce an alternate frequency and regained control of the situation. Although nothing happened, the conditions were getting good for an airspace conflict. If a crew is operating in a TCA below 10000' (which I presumed, since they were sharing our control frequency), it would seem to be an unsafe practice to be discussing anything other than pertinent flight information during such a critical phase. Inadvertently jamming a frequency with a stuck microphone is understandable but such cockpit discipline in a busy TCA is dangerous! Maybe that is why the sterile cockpit rule was written.

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Original NASA ASRS Text

Title: A FLT IN DCA AREA ON TRACON FREQ HAD A STUCK MIKE ALLOWING COCKPIT CONVERSATION TO BE BROADCAST AND BLOCKING THE FREQ. APCH CTLR MANAGED TO SWITCH EVERYONE TO AN ALTERNATE FREQ.

Narrative: SHORTLY AFTER SWITCHING TO WASHINGTON'S FINAL APCH CTLR, AN ACFT BEGAN BROADCASTING ON THE FREQ WITH A STUCK MIC. THE AIRCREW MAINTAINED A STEADY STREAM OF CONVERSATION NOT PERTINENT TO THEIR FLYING DUTIES AND EFFECTIVELY JAMMING THE FREQ WHILE WE WERE AWAITING FURTHER VECTORS FOR SEQUENCING INTO WASHINGTON NATIONAL DURING THE AFTERNOON RUSH. FORTUNATELY, THE ALERT CTLR MANAGED TO ANNOUNCE AN ALTERNATE FREQ AND REGAINED CTL OF THE SITUATION. ALTHOUGH NOTHING HAPPENED, THE CONDITIONS WERE GETTING GOOD FOR AN AIRSPACE CONFLICT. IF A CREW IS OPERATING IN A TCA BELOW 10000' (WHICH I PRESUMED, SINCE THEY WERE SHARING OUR CTL FREQ), IT WOULD SEEM TO BE AN UNSAFE PRACTICE TO BE DISCUSSING ANYTHING OTHER THAN PERTINENT FLT INFO DURING SUCH A CRITICAL PHASE. INADVERTENTLY JAMMING A FREQ WITH A STUCK MIC IS UNDERSTANDABLE BUT SUCH COCKPIT DISCIPLINE IN A BUSY TCA IS DANGEROUS! MAYBE THAT IS WHY THE STERILE COCKPIT RULE WAS WRITTEN.

Data retrieved from NASA's ASRS site as of July 2007 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.