OH-58Ds and their pilots get the most flight time of any airframe both deployed and in garrison for a few reasons: cheap to operate (only single engine aircraft in the Army which leads to much lower cost per flight hour (fuel/mx), and there are no flight simulators for the aircraft (except for the 2 new ones at Fort Rucker), so you need real flight hours to meet semiannual minimum flight hour requirements.

Budget cuts are here. Once the wars are over, flight time will be way harder to come by, especially for the maintenance hogs (AH-64Ds and CH-47s).

Fun mission too...