The A-10 is one of the most popular aircraft in the US inventory. This is especially true among infantry and other ground forces, where it has achieved rock-star status due to its ability to provide Close Air Support (CAS) during intense fighting. However, the A-10 is not without its critics, as many top-level Air Force officials feel that the CAS mission can be absorbed by the F-35 and MQ-9 Reaper Unmanned Aerial Systems (UAS).