Plain English Meaning

The most common type of precision approach. The pilot can descend through cloud or low visibility to 200 feet above the runway before having to see the runway environment. If the runway isn't in sight by then, the pilot must go around.

Full Definition

A class of precision instrument approach that provides vertical and lateral guidance allowing descent to a decision height (DH) no lower than 200 feet above the touchdown zone, with a runway visual range (RVR) generally no less than 1,800 feet (with appropriate lighting, otherwise 2,400 feet). Category I (CAT I) approaches can be flown using , and with the ), suitably equipped receivers can also fly approaches to CAT I via .