Alaska Airlines said Aug. 30 Singapore Airlines will be its newest global partner. Members of Alaska Airlines’ Mileage Plan and Singapore Airlines’ KrisFlyer loyalty programs will begin earning miles on each other’s flights beginning Sept. 27. Mileage Plan members will be able to redeem miles for travel awards on Singapore Airlines-operated flights at a later date. In addition, the two carriers will enact a codeshare partnership, pending government approval. Virgin America …