Narrative:

After takeoff to the north from dca, at a point about 5 mi up the river, dca departure control notified us that it appeared that our aft airstairs were down (or came down?) at takeoff rotation. After short consideration, we declared an emergency and landed, overweight by about 4000#, on the takeoff runway west/O control problem or incident. The value of this report, I believe, will be in treating the chain of events which could have allowed this to have happened. The aircraft in question first came into dca with a log book write-up re: an aft airstair door annunciator light in flight. There have been numerous previous log book entries re: this. In addition, the first officer mentioned that he had previously had the same aircraft with the pesky light problem. Maintenance investigated the write-up, and wrote it off as a microswitch that we found loose and was set and tightened with the oral comment that if it comes on again it may need further adjustment in bos (our destination), and that the aft airstairs were indeed up and secure. It was with this understanding of it being a micro-switch problem that I, the captain, made a bad call. At times, on pushback from the gate, that same light for a moment was flickering, and knowing the aforedescribed background accepted that during the checklist. I should have returned to the gate, for as it turned out, later maintenance investigation revealed a more extensive aft airstair rigging (?) problem.

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Original NASA ASRS Text

Title: ACR LGT RECEIVES REPORT FROM DEP CTL THAT AFT STAIRS WERE OBSERVED BY TWR CTLR TO PARTIALLY DEPLOY UPON ACFT'S ROTATION DURING TKOF.

Narrative: AFTER TKOF TO THE N FROM DCA, AT A POINT ABOUT 5 MI UP THE RIVER, DCA DEP CTL NOTIFIED US THAT IT APPEARED THAT OUR AFT AIRSTAIRS WERE DOWN (OR CAME DOWN?) AT TKOF ROTATION. AFTER SHORT CONSIDERATION, WE DECLARED AN EMER AND LANDED, OVERWT BY ABOUT 4000#, ON THE TKOF RWY W/O CTL PROB OR INCIDENT. THE VALUE OF THIS RPT, I BELIEVE, WILL BE IN TREATING THE CHAIN OF EVENTS WHICH COULD HAVE ALLOWED THIS TO HAVE HAPPENED. THE ACFT IN QUESTION FIRST CAME INTO DCA WITH A LOG BOOK WRITE-UP RE: AN AFT AIRSTAIR DOOR ANNUNCIATOR LIGHT IN FLT. THERE HAVE BEEN NUMEROUS PREVIOUS LOG BOOK ENTRIES RE: THIS. IN ADDITION, THE F/O MENTIONED THAT HE HAD PREVIOUSLY HAD THE SAME ACFT WITH THE PESKY LIGHT PROB. MAINT INVESTIGATED THE WRITE-UP, AND WROTE IT OFF AS A MICROSWITCH THAT WE FOUND LOOSE AND WAS SET AND TIGHTENED WITH THE ORAL COMMENT THAT IF IT COMES ON AGAIN IT MAY NEED FURTHER ADJUSTMENT IN BOS (OUR DEST), AND THAT THE AFT AIRSTAIRS WERE INDEED UP AND SECURE. IT WAS WITH THIS UNDERSTANDING OF IT BEING A MICRO-SWITCH PROB THAT I, THE CAPT, MADE A BAD CALL. AT TIMES, ON PUSHBACK FROM THE GATE, THAT SAME LIGHT FOR A MOMENT WAS FLICKERING, AND KNOWING THE AFOREDESCRIBED BACKGROUND ACCEPTED THAT DURING THE CHKLIST. I SHOULD HAVE RETURNED TO THE GATE, FOR AS IT TURNED OUT, LATER MAINT INVESTIGATION REVEALED A MORE EXTENSIVE AFT AIRSTAIR RIGGING (?) PROB.

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.