N2S Yellow PerilBoeing N2S Stearman Yellow Peril airplane model. The famed Stearman Model 75 has its roots in the earlier Model 70, which was chosen in 1934 as the U. S. Navy's primary trainer. At a time when biplanes were becoming a thing of the past, the Model 70 offered the fledgling pilot a steady and sturdy steed. Designed and built in only 60 days, the prototype Model 70 could withstand load factors much higher than were expected to occur in normal flight