When the owner of Waggoner Aircraft, a major aircraft manufacturing company, dies in a midair collision, his stepson tries to run the company and fails. As the business flounders, a raider takes control and sends in a new management team. Ben Carson, the new boss, is met with hostility. In a 'step over the line' confrontation, he fires all the test pilots.
Sunny Merlin, company radio operator and highly qualified aviator, has been trying to crack the all-male club of test pilots. With the regulars gone, she seizes the opportunity and begins flying.
Bad luck plagues the company, and the innovative ideas of a yonng engineer are suspect in several accidents.
At an inopportune moment, Sunny participates in a long distance flight for charity. When the airplane breaks, only the extraordinary skill of Sunny Merlin can save the passengers and the crippled plane.