Narrative:

When approaching dca, we were cleared down to 8000' MSL. We were talking with dulles en route (controller was busy). As we were about to level off at 8000', dulles en route came over the frequency and called for an immediate right turn--traffic was 12 O'clock passing at 7000'. He then quickly told us to switch over to washington approach. As I was switching frequency and the captain watching out for the traffic and making the immediate right turn, we both heard the altitude alert go off. By the time the captain reacted, the aircraft had lost a total of 500'. He quickly regained the lost altitude. I feel that factors contributing to the excess altitude loss were the controller's tone of voice in expressing the immediate right turn, and traffic passing underneath, causing captain to divert his attention outside the aircraft at a critical stage of flight (leveling off from an assigned altitude). Another factor was the frequency change, diverting my attention to the radio for the frequency change, which was made urgent by dulles en route. I guess this shows that the PF should fly the plane and the PNF should accomplish all other tasks.

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Original NASA ASRS Text

Title: ARRIVING, DESCENDING ACFT LOSES 500' IN EXPEDITED TURN. FLT CREW GIVEN TRAFFIC ADVISORY AND ASSUMED THAT THE SITUATION WAS URGENT. NOT KNOWN WHY TRACON APCH CTLR SEEMED URGENT IN HIS ISSUANCE OF TURN, WHEN OPPOSITE DIRECTION TRAFFIC WAS 1000' BELOW INITIALLY. POSSIBLE LOSS OF SEPARATION AND LESS THAN STANDARD SEPARATION.

Narrative: WHEN APCHING DCA, WE WERE CLRED DOWN TO 8000' MSL. WE WERE TALKING WITH DULLES ENRTE (CTLR WAS BUSY). AS WE WERE ABOUT TO LEVEL OFF AT 8000', DULLES ENRTE CAME OVER THE FREQ AND CALLED FOR AN IMMEDIATE RIGHT TURN--TFC WAS 12 O'CLOCK PASSING AT 7000'. HE THEN QUICKLY TOLD US TO SWITCH OVER TO WASHINGTON APCH. AS I WAS SWITCHING FREQ AND THE CAPT WATCHING OUT FOR THE TFC AND MAKING THE IMMEDIATE RIGHT TURN, WE BOTH HEARD THE ALT ALERT GO OFF. BY THE TIME THE CAPT REACTED, THE ACFT HAD LOST A TOTAL OF 500'. HE QUICKLY REGAINED THE LOST ALT. I FEEL THAT FACTORS CONTRIBUTING TO THE EXCESS ALT LOSS WERE THE CTLR'S TONE OF VOICE IN EXPRESSING THE IMMEDIATE RIGHT TURN, AND TFC PASSING UNDERNEATH, CAUSING CAPT TO DIVERT HIS ATTN OUTSIDE THE ACFT AT A CRITICAL STAGE OF FLT (LEVELING OFF FROM AN ASSIGNED ALT). ANOTHER FACTOR WAS THE FREQ CHANGE, DIVERTING MY ATTN TO THE RADIO FOR THE FREQ CHANGE, WHICH WAS MADE URGENT BY DULLES ENRTE. I GUESS THIS SHOWS THAT THE PF SHOULD FLY THE PLANE AND THE PNF SHOULD ACCOMPLISH ALL OTHER TASKS.

Data retrieved from NASA's ASRS site as of August 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.