Complex sentence: In 1937, the K-2 was ordered from Goodyear as part of a contract that also bought the L-1 which was Goodyear's standard advertising and passenger blimp.
Split into simpler sentences: In 1937, the K-2 was ordered from Goodyear as part of a contract that also bought the L-1. The L-Class was Goodyear's standard advertising and passenger blimp.