Narrative:

During descent into dca, approach cleared for to 5000 ft and captain (PF) went down to approximately 4600 ft prior to correction back to assigned altitude. Copilot missed 1000 ft above callout due to head down identing ILS and outer compass locator -- no excuse sirs, bad situational awareness on my part. Copilot asked approach if there was a problem/conflict and approach said 'no problems.' there was no one around us that late at night -- luckily. Approach cleared us to 2500 ft and then for a visual after copilot called field and wilson bridge in sight for the captain. Captain then accidentally went below recommended 1600 ft altitude outside 5.6 DME while aligning aircraft with the river. The rest of approach and landing was uneventful. I have 'relearned' many lessons from this event. Unfortunately lapses in attention can cause incidents, but fortunately escapes and reflection will permit me the opportunity to rededicate my efforts to concentrate even more when late night, routine arrs to familiar fields can lull anyone into complacency. Supplemental information from acn 479734: I was in a hurry to descend. I ignored the 5000 ft clearance. The autoplt was engaged, but with the descent rate which I had set up, we descended to 4500 ft. It was early morning and it had been a long 3 days. I was confused because I was very fatigued.

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Original NASA ASRS Text

Title: A LATE NIGHT ARR AT DCA IS PLAGUED BY SEVERAL LAPSES IN OPERATING PROCS BY A FATIGUED AND COMPLACENT CREW.

Narrative: DURING DSCNT INTO DCA, APCH CLRED FOR TO 5000 FT AND CAPT (PF) WENT DOWN TO APPROX 4600 FT PRIOR TO CORRECTION BACK TO ASSIGNED ALT. COPLT MISSED 1000 FT ABOVE CALLOUT DUE TO HEAD DOWN IDENTING ILS AND OUTER COMPASS LOCATOR -- NO EXCUSE SIRS, BAD SITUATIONAL AWARENESS ON MY PART. COPLT ASKED APCH IF THERE WAS A PROB/CONFLICT AND APCH SAID 'NO PROBS.' THERE WAS NO ONE AROUND US THAT LATE AT NIGHT -- LUCKILY. APCH CLRED US TO 2500 FT AND THEN FOR A VISUAL AFTER COPLT CALLED FIELD AND WILSON BRIDGE IN SIGHT FOR THE CAPT. CAPT THEN ACCIDENTALLY WENT BELOW RECOMMENDED 1600 FT ALT OUTSIDE 5.6 DME WHILE ALIGNING ACFT WITH THE RIVER. THE REST OF APCH AND LNDG WAS UNEVENTFUL. I HAVE 'RELEARNED' MANY LESSONS FROM THIS EVENT. UNFORTUNATELY LAPSES IN ATTN CAN CAUSE INCIDENTS, BUT FORTUNATELY ESCAPES AND REFLECTION WILL PERMIT ME THE OPPORTUNITY TO REDEDICATE MY EFFORTS TO CONCENTRATE EVEN MORE WHEN LATE NIGHT, ROUTINE ARRS TO FAMILIAR FIELDS CAN LULL ANYONE INTO COMPLACENCY. SUPPLEMENTAL INFO FROM ACN 479734: I WAS IN A HURRY TO DSND. I IGNORED THE 5000 FT CLRNC. THE AUTOPLT WAS ENGAGED, BUT WITH THE DSCNT RATE WHICH I HAD SET UP, WE DSNDED TO 4500 FT. IT WAS EARLY MORNING AND IT HAD BEEN A LONG 3 DAYS. I WAS CONFUSED BECAUSE I WAS VERY FATIGUED.

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.