Definition
An air traffic control procedure permitting takeoffs and landings to occur at the same time on two runways that physically cross or converge, using prescribed separation criteria to keep aircraft clear of the intersection or one another. SOIR requires specific weather minimums, defined hold-short points, and pilot acknowledgment of any 'land and hold short' (LAHSO) instructions.
Plain English
It is a way for the tower to use two crossing runways at the same time. One aircraft may need to land and stop before the crossing point, or take off in a sequence timed so the paths don't conflict.
Context Anchor
Seen in FAA acronym lists, airport operating procedures, and control tower discussions about how busy airports use crossing runways.
Why Pilots Care
Requires precise timing and communication to prevent conflicts or runway incursions when runways intersect.
Grounding Statement
Picture two runways forming an X; SOIR is the tower-controlled use of both without letting aircraft arrive at the crossing area together.
Intuition Check
Do not assume SOIR means the runways are independent just because both are active. It means special procedures are being used because the runways, or the paths from them, can conflict.
Example Sentence 1
Tower advised SOIR was in effect and asked if we could accept a land and hold short clearance for runway 27.
Example Sentence 2
Pilots review SOIR procedures before operating at airports where runways cross.