Parallel Precision: What Is A Simultaneous Offset Instrument Approach?

Simultaneous approaches to parallel runways were the topic of a recent article that discussed the PRM approach. The precision runway monitoring system allows approach operations to runways as close as 2500 feet apart (as measured by the distance from one runway's centerline to the other). This criterion gets the job done at most airports, but there are a few places where operational needs dictate having approaches to runways that are even closer. For this, the SOIA approach was developed.