Scope Clause - Wikipedia⁠↗

The scope clause’s goal is to protect the union pilots’ jobs at the major airline from being outsourced by limiting the regional airlines’ passenger capacity.1(https://en.wikipedia.org/wiki/Scope_clause#cite_note-1) These clauses exist primarily in the United States, Canada, and Mexico.

Scope clauses have a major influence on manufacturers of regional aircraft. Manufacturers will create airplanes specifically tuned to the scope clauses of most airlines. For this reason and others, regional aircraft tend to be manufactured in families, and competing regional aircraft will often have identical seating capacity.

United is seeking to fly more aircraft in the 76-seat category, given that no manufacturers currently produce 50-seaters.