This operation comprises one ILS and one LDA with glide slope. The ILS is aligned with its runway, but the LDA serving the second runway is offset (between 2.5° and 3°) from a parallel track. This offset permits simultaneous instrument approach operations to parallel runways spaced less than 3,000 feet apart, but no less than 750 feet. Because of the offset, this operation is also known as an SOIA.
