Factbox-Flights, airports affected by U.S. FAA system outage

American Airlines planes are seen at the Tampa International Airport

LONDON (Reuters) -U.S. flights were slowly beginning to resume departures and a ground stop was lifted after the Federal Aviation Administration (FAA) scrambled to fix a system outage overnight that forced a halt to all U.S. departing flights.

Here's what we know so far:


* A total of 4,314 flights were delayed within, into or out of the United States as of 1411 GMT, flight tracking website FlightAware showed, without specifying the cause of the delays

* Another 758 flights within, into or out of the country were cancelled

* Some 21,464 flights are scheduled to depart airports in the United States on Wednesday with a carrying capacity of nearly 2.9 million passengers, data from Cirium shows

* American Airlines has the most departures from U.S. airports with 4,819 flights scheduled, followed by Delta Air Lines and Southwest Airlines, the Cirium data showed


* The operator of Paris' international airports - Paris Charles de Gaulle and Orly - said it expects delays to flights.

* Virgin Atlantic said some U.S. departures may be affected by the outage and asked customers due to travel on Wednesday to check their flight status.

* Air France, Lufthansa, British Airways and Iberia, which are both owned by IAG, continue to operate flights to and from the United States as normal for now.

* Iberia said it could operate with an alternative system, while the French airline said it was monitoring the situation.

* Scandinavian airline SAS said it is not affected. It has one flight due to land in the United States later on Wednesday.

(Reporting by Reuters; compiled by Josephine Mason; editing by Jason Neely and Conor Humphries)