From 1967 to 2011, three platforms were used at the LC-39 to support NASA's launch vehicles. Formerly called Mobile Launchers (ML), the mobile launcher platforms were constructed for transporting and launching the Saturn V rocket for the Apollo program lunar landing missions of the 1960s and 1970s. Each ML originally had a single exhaust vent for the Saturn V's engines. The Mobile Launchers also featured a Launch Umbilical Tower (LUT) with nine swing arms that permitted servicing of the vehicle on the launch pad, and swung away from it at launch.