The Mega Airport London Heathrow Xtended Addon for Flight Simulator X is an expansion pack published by Aerosoft in 2004. This simulation game is designed for PC and is compatible with Microsoft Flight Simulator X. The add-on includes additional features and enhances the gaming experience by adding a more realistic and detailed representation of London Heathrow Airport. With a 3+ age rating, this expansion pack offers a comprehensive and immersive simulation of air travel at one of the world's busiest airports.