Plain English Meaning
Two or more aircraft flying instrument approaches to side-by-side runways at the same airport at the same time, under specific rules that keep them safely separated.
Full Definition
Instrument approaches conducted at the same time to parallel runways at the same airport. Depending on runway spacing and the procedures in use, simultaneous approaches may be independent (each aircraft tracked by its own controller and monitored to ensure separation from the parallel approach) or dependent (aircraft on adjacent finals must remain staggered by a specified distance). Simultaneous approaches require specific ATC authorization, published procedures, and pilot acknowledgment.
Context Anchor
Seen in instrument flying when airports use parallel runways and allow aircraft to those runways at the same time.