SAN FRANCISCO (CBS SF) – Forty-two flights coming into or heading out of San Francisco International Airport have been canceled Wednesday, as air traffic is operating on only three of the airport’s four runways while the investigation into Saturday’s deadly plane crash on Runway 28L continues.

Airport Duty Manager Linda Perry said that as of mid-morning, there were delays of 30 minutes to an hour for arriving flights. She said that 20 departing flights and 22 arriving flights had been canceled.

“There are less delays right now than yesterday, but it is still early in the day,” Perry warned.

Travelers were advised to contact their airline carriers for real-time delay and cancellation information, Perry said.

The wreckage from Asiana Airlines Flight 214 can be seen by passengers landing at and leaving SFO. There is no estimate yet as to when the runway will be cleared and in operation, Perry said.

Flight 214 crashed around 11:30 a.m. Saturday, resulting in the deaths of two passengers and injuring more than 180 people. National Transportation Safety Board investigators are continuing to probe the crash.

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