When in doubt, spell it out. The NTSB hopes to make it easier for pilots flying into Seattle-Tacoma International Airport to land in the right spot by urging the FAA to clearly mark a taxiway that has been accidentally used as a runway several times in the last few years. In the most recent incident on Jan. 19 an Air Canada Jazz Dash-8 landed on Taxiway Tango at Sea-Tac on a VFR approach to Runway 16R. It was about the fifth such incident in recent years. The NTSB hopes to put an end to it with some old-fashioned signage. Recognizing that such markings are not currently "nonstandard," the NTSB wants the FAA to paint, in large letters, the word TAXIWAY at intervals running the length of the asphalt. In between the lettering, the centerline is to be overpainted with a continuous serpentine line. The NTSB also wants the FAA to research and establish marking standards for airports that have recurring problems with taxiway landings.