Narrative:

Local and ground control combined. Runway 5 in use (approach end difficult to see because of poorly mounted ramp lights, darkness, rain and obstructions). Several mins after I assumed local control and ground control a DC9 called, 'ready.' I assumed the aircraft meant ready to taxi because on the position relief from the other controller nothing was mentioned about a DC9 taxiing, the aircraft identify was not written down on the scratch pad, and the flight progress strip was in the inactive bay. I responded 'air carrier X taxi runway 5.' aircraft responded 'air carrier X roger.' I did not have any ground traffic between DC9's ramp and runway. I looked toward the ramp and saw an aircraft which I assumed was the DC9, but was an aircraft parked nearby. I cleared the B737 to land (WX 400 ft overcast). The DC9 asked 'what runway were we using?' I responded runway 5. DC9 then asked where the B737 was. I responded a 1 1/2 mi final. The DC9 then informed me that he was on the runway. The B737 was on a short final at which time he was sent around. Causes: poor position relief by preceding controller. Assumption by DC9 pilot that 'taxi runway 5' meant that he could taxi into position. No readback by pilot. Lighting conditions. Assumption by myself that parked aircraft was the taxiing aircraft.

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Original NASA ASRS Text

Title: A DC9 AT THE BUF ARPT, HOLDING SHORT OF THE RWY, TAXIED INTO POS WHEN THE CTLR SAID, TAXI TO RWY 5. TFC ON SHORT FINAL WAS SENT AROUND.

Narrative: LCL AND GND CTL COMBINED. RWY 5 IN USE (APCH END DIFFICULT TO SEE BECAUSE OF POORLY MOUNTED RAMP LIGHTS, DARKNESS, RAIN AND OBSTRUCTIONS). SEVERAL MINS AFTER I ASSUMED LCL CTL AND GND CTL A DC9 CALLED, 'READY.' I ASSUMED THE ACFT MEANT READY TO TAXI BECAUSE ON THE POS RELIEF FROM THE OTHER CTLR NOTHING WAS MENTIONED ABOUT A DC9 TAXIING, THE ACFT IDENT WAS NOT WRITTEN DOWN ON THE SCRATCH PAD, AND THE FLT PROGRESS STRIP WAS IN THE INACTIVE BAY. I RESPONDED 'ACR X TAXI RWY 5.' ACFT RESPONDED 'ACR X ROGER.' I DID NOT HAVE ANY GND TFC BTWN DC9'S RAMP AND RWY. I LOOKED TOWARD THE RAMP AND SAW AN ACFT WHICH I ASSUMED WAS THE DC9, BUT WAS AN ACFT PARKED NEARBY. I CLRED THE B737 TO LAND (WX 400 FT OVCST). THE DC9 ASKED 'WHAT RWY WERE WE USING?' I RESPONDED RWY 5. DC9 THEN ASKED WHERE THE B737 WAS. I RESPONDED A 1 1/2 MI FINAL. THE DC9 THEN INFORMED ME THAT HE WAS ON THE RWY. THE B737 WAS ON A SHORT FINAL AT WHICH TIME HE WAS SENT AROUND. CAUSES: POOR POS RELIEF BY PRECEDING CTLR. ASSUMPTION BY DC9 PLT THAT 'TAXI RWY 5' MEANT THAT HE COULD TAXI INTO POS. NO READBACK BY PLT. LIGHTING CONDITIONS. ASSUMPTION BY MYSELF THAT PARKED ACFT WAS THE TAXIING ACFT.

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.