Air Traffic Control Fully Certified
Other / Unknown; Situational Awareness
ATC Issue All Types
General None Reported / Taken
ATC Equipment / Nav Facility / Buildings; Procedure
I was working Local Control and Approach APREQed a VOR Runway 2 approach. I knew that this approach had had an issue several days earlier that Flight Check had checked and deemed to be within tolerance. I was watching the aircraft on the approach and at approximately a five mile final; the aircraft veered west of course and was no longer on the approach. I knew the aircraft was below the clouds doing this approach as practice IFR. I informed the pilot that he was west of course and he advised that he was correcting. I knew that the approach had been flight tested the day before and deemed appropriate but I still wanted to pay extra close attention to the approach. This approach; VOR Runway 2; into SGF has an issue. Aircraft veer west of course even though the approach should keep aircraft on the east side of the runway for the duration. This approach needs to be further investigated immediately! The approach has already locally been deemed unusable until further action is taken. I would recommend all controllers watch aircraft courses.
SGF Controller voiced concern regarding the accuracy of the VOR Runway 2 Approach Procedures; noting that even after a Flight Check aircraft appeared to veer West of the final approach course.