NWA operates 30 B747's. Sixteen of these are 747-400 that are flown by 2 pilot crews augmented on long flights with additional pilots. NWA also operates 14 B747-200's. Twelve of these are freighters based in ANC and two are passenger aircraft dedicated to charters and are based in MSP. All of these 200 series require a 3 pilot crew (Captain, FO, and Flight Engineer). Because it is a three man crew they can fly up to 12 hour legs without extra crew. This why you saw an SO pay scale and it is in the new DAL contract.