Originally Posted by iPilot

Exactly. If a DCI carrier strikes Delta already set it up so most markets are served by multiple regionals and their mainline jets. Though other regionals can't pick up extra flying they can still serve a good portion of their customers through a strike and just operate on a limited basis.

Spirit, on the other hand, was completely and utterly crippled by their strike. They had no regional partners to rely on and couldn't set up charter contracts to fly struck work. Had they had contract lift already going they could in theory rely on them since it wouldn't be struck work but still get at least a portion of their passengers on their way.

Regionals by definition get around the union's ability to raise wages by taking away the one thing the union had which was a monopoly on labor.