Under the upkeep maintenance category what is special?
This inspection is a scheduled inspection with a prescribed interval other than daily or phase. The intervals are specified in the applicable PMS publication and are based on elapsed calendar time, flight hours, operating hours, or number of cycles or events, for example, 7, 28 days; 50, 100, 200 hours; 10, 100 arrestments; or 5,000 rounds fired. In some cases, aircraft special inspections contain within them engine inspection requirements. They are referred to as combined airframe and engine special inspections.