NY -- Standard&Poor's CreditWire 9/30/98 – Standard&Poor's today assigned its single-'A'-plus underlying rating (SPUR) to San Francisco Airport Commission, Calif.'s $260.78 million second series revenue bonds (issue 20 refunding bonds) and $89.23 million second series revenue bonds (issue 21 bonds), dated Oct. 1, 1998 due May 1, 2029. The bonds are scheduled to sell Oct. 1, 1998, and are expected to receive a triple-'A' rating based on bond insurance. The rating reflects the following strengths: -- Greater certainty associated with completion of Near Term Master Plan (NTMP) project budgets, -- Demonstrated and expected solid economic underpinnings and positive traffic trends that slowed in fiscal 1998, and -- Strong financial performance and debt service coverage. Offsetting credit