London, Apr 5 (IANS): Heathrow airport unveiled a new temporary terminal to cater to athletes and officials involved with London Olympics 2012.

The terminal has been built solely for "Games Family" departures, and will be used for the three days after the closing ceremony Aug 12.

Construction of the terminal - which is roughly the size of three Olympic swimming pools - began in February in an area currently used for staff car parking on the south side of the airport, Xinhua reported.

No flights will leave from the terminal, so athletes will be bussed to departure lounges.

With 31 check-in desks and seven security lanes, athletes will take just 30 minutes to pass through the facility, according to BAA director for London 2012 Andy Garner.

Many will also be able to check in their luggage at the Olympic Village, ahead of arriving at the airport.

Heathrow says June 27 to Oct 1 will be its critical period - allowing time either side of the start of the Olympics and the end of the later Paralympic Games.

On its busiest expected days - July 26 and Aug 13 - it predicted passenger levels would increase from an estimated 95,000 on a usual day by 45 percent to 138,000.

Heathrow is expecting a 35 percent increase in baggage July 26 and Aug 13, with around 15 percent of the 200,000 items expected on those days likely to be oversized luggage such as sporting equipment.