Narrative:

On ILS to runway 1L at iad. WX 1200 ft broken visibility 8 NM. Crowded ILS pattern. Approach control very busy. After visually acquiring the runway, I saw what appeared to be a regional jet on the runway. I remarked to my first officer that the jet was probably in position for takeoff. Tower issued us landing clearance. Passing 500 ft AGL, we realized that the jet had actually landed prior to us and was still on the runway. It appeared the jet had touched down 'on the numbers' and rolled out leisurely on the runway. I said to my first officer, 'get ready for a go around' because he hadn't yet cleared runway 1L. Tower controller apparently did not notice what was transpiring. At 50-75 ft AGL, tower said 'air carrier X, go around.' I said to the first officer, 'that isn't us.' I noticed the jet clearing at taxiway Y4 while at 50 ft AGL in the landing flare, so I landed, exiting the runway at taxiway Y2. On rollout we heard air carrier X (the one who had been given the go around) state that he was, in fact, holding short for takeoff. I believe that the controller, upon seeing the conflict, issued the miss to us but used the wrong call sign. I do not know if a loss of separation occurred. A contributing confusion factor may have been that we were using a radio call sign of air carrier Z instead of the usual air carrier Y.

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Original NASA ASRS Text

Title: B777 RPTS POSSIBLE CONFLICT AT DIA WITH 2 ARR ACFT.

Narrative: ON ILS TO RWY 1L AT IAD. WX 1200 FT BROKEN VISIBILITY 8 NM. CROWDED ILS PATTERN. APCH CTL VERY BUSY. AFTER VISUALLY ACQUIRING THE RWY, I SAW WHAT APPEARED TO BE A REGIONAL JET ON THE RWY. I REMARKED TO MY FO THAT THE JET WAS PROBABLY IN POS FOR TKOF. TWR ISSUED US LNDG CLRNC. PASSING 500 FT AGL, WE REALIZED THAT THE JET HAD ACTUALLY LANDED PRIOR TO US AND WAS STILL ON THE RWY. IT APPEARED THE JET HAD TOUCHED DOWN 'ON THE NUMBERS' AND ROLLED OUT LEISURELY ON THE RWY. I SAID TO MY FO, 'GET READY FOR A GAR' BECAUSE HE HADN'T YET CLRED RWY 1L. TWR CTLR APPARENTLY DID NOT NOTICE WHAT WAS TRANSPIRING. AT 50-75 FT AGL, TWR SAID 'ACR X, GO AROUND.' I SAID TO THE FO, 'THAT ISN'T US.' I NOTICED THE JET CLRING AT TXWY Y4 WHILE AT 50 FT AGL IN THE LNDG FLARE, SO I LANDED, EXITING THE RWY AT TXWY Y2. ON ROLLOUT WE HEARD ACR X (THE ONE WHO HAD BEEN GIVEN THE GAR) STATE THAT HE WAS, IN FACT, HOLDING SHORT FOR TKOF. I BELIEVE THAT THE CTLR, UPON SEEING THE CONFLICT, ISSUED THE MISS TO US BUT USED THE WRONG CALL SIGN. I DO NOT KNOW IF A LOSS OF SEPARATION OCCURRED. A CONTRIBUTING CONFUSION FACTOR MAY HAVE BEEN THAT WE WERE USING A RADIO CALL SIGN OF ACR Z INSTEAD OF THE USUAL ACR Y.

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.