US Airways will begin service to London’s Heathrow Airport from Philadelphia on March 29, 2008. This will be the first ever US Airways service to Heathrow. Tickets are currently available for sale as of Dec. 1, so it’s a good time to check for award seats. The daily nonstop flights increase US Airways’ European destinations from Philadelphia to 20. US Airways has also reported that it plans to add approximately three to four new international markets per year between 2009 and 2011.