The Transportation Security Administration’s PreCheck program, which offers expedited screening to pre-approved passengers, is continuing to expand. JetBlue will likely become a participating airline by the end of this year, according to a post last Friday on the TSA blog. US Airways, United Airlines and Alaska Airlines already were slated to join the program in the coming months. Currently, select frequent flyers on American Airlines and Delta Air Lines have been tapped to participate. Details about the program and its expansion are available at http://www.tsa.gov/what_we_do/escreening.shtm.