Medium Transport
Confusion; Situational Awareness
ATC Issue All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Issued Advisory / Alert; Air Traffic Control Issued New Clearance; Flight Crew Executed Go Around / Missed Approach
Human Factors
We had been on RWY 23 for the majority of my shift; I thought we were still on 23. I vectored the aircraft to 23 and the pilot never questioned it although he had the current ATIS which stated runway five. The pilot never descended below the MVA and then was vectored to RWY 5.
While enroute; we checked the ATIS and the broadcast said that 'ILS Runway 5' was in use. So we prepared for the ILS 5 and briefed the approach. Upon reaching the airport vicinity and being handed off to approach; the Charleston Approach Controller told us that the ILS Runway 23 was now in use; which was basically straight in from our present track. We prepared for the ILS 23 and briefed the approach. We were cleared to join the localizer and cleared for the ILS 23. I could hear a faint Morse code identifier when I identified the localizer. The flight director and autopilot captured the course. Approach told us to contact Charleston Tower. The Tower cleared us to land on Runway 23. The flight director and autopilot then captured the Glideslope. We noticed that the autopilot seemed to start to have problems tracking the flight director. Then both of us noticed that we started to get erratic indications from the flight director and our instruments (which we did not get until that point - up until then; the course needle and glideslope were centered and captured); so we performed the missed approach SOP. We told the Tower we had gone missed and he had us fly the runway heading and contact Charleston Approach again. Charleston Approach then told us that that they had been using Runway 23 earlier in the day and had switched to Runway 5 and that he had forgotten that they were now set up for the ILS 5. He told us that the Localizer and Glideslope for Runway 23 were not turned on and apparently; we were tracking 'false signals' from the ILS 5 Localizer and Glideslope antennas. It appears that the ILS approaches for Runways 5 and 23 use the same Localizer antennas. We asked him to repeat that he had cleared us for the ILS 23 when the Antenna was configured for the ILS 5 and he said yes. He then told us that he could give us vectors for the ILS Runway 5. So we set up our instruments for the ILS 5 and briefed it. We flew the ILS 5 approach and landed without any further problems.
Two Air Carrier pilots and the Approach Controller involved describe being vectored for the ILS 23 at CRW while Runway 5 is the active runway and ILS. The autopilot captures a false signal initially; that quickly becomes erratic and a go- around is initiated and the mistake is discovered.