The markings on a runway are there to help the pilot aim for the proper touchdown point. Shortly before the Asiana 214 crash, SFO moved the touchdown point for runway 28L several hundred feet down the runway. SFO was thus required to remove the old markings, and paint on new ones that matched the new touchdown point. The airport was not permitted to simply paint over the old markings with black paint. It was supposed to remove the old markings entirely. According to the FAA:
Pavement markings that are no longer needed are not to be painted over but instead are to be physically removed. Removal of markings is achieved by water blasting, shot blasting, sand blasting, chemical removal, or other acceptable means that do not harm the pavement. The FAA does not endorse painting over the old marking because this practice merely preserves the old marking, which is some cases have misled pilots . . .
Look at the photo at right from the New York Post. It is clear that SFO did exactly the wrong thing – when they moved the touchdown point, they painted over the old markings instead of removing them.
Was this yet another factor that the crew of Asiana Flight 214 had to deal with?
So far, the NTSB has not mentioned the improper runway markings. We’ll see if it comes up in today’s briefing.