Dozens of flights were delayed and diverted when the runway at Gatwick was closed due to a suspected oil spillage.
A spokesman for the West Sussex airport said the runway was shut shortly after 10.15am and did not reopen until 11.38am.
According to Gatwick's website at least 19 incoming flights were diverted to other airports, and a number of departing services were delayed.
An airport spokesman said: "Arriving and departing flights recommenced from Gatwick at 11.38am.
"The runway closure has caused some flights to be diverted to other airports in the area and there will be delays to some departing flights.
"Friends and family waiting for passengers should contact the relevant airline for the latest information."