http://biz.yahoo.com/ap/060310/northwest_subsidiary.html?.v=3
Northwest Airlines Corp. said it has bought the operating certificate of bankrupt FLYi Inc., a key move toward starting a new subsidiary for regional flying.
Northwest will pay $2 million for the certificate, FLYi disclosed in a bankruptcy court filing. The Federal Aviation Administration requires airlines to have operating certificates, and buying someone else's is considered easier than completing the paperwork to start one from scratch.