As quoted from Squadron/Signal Publications: "In Action books, despite the title of the genre, are books that trace the development of a single type of aircraft, armored vehicle, or ship from the prototype to the final production variant. Experimental or "one-off" variants can also be included. Our first In Action book was printed in 1971."
In the mid to late thirty's the U.S. Navy was looking for a new high speed, high altitude fighter. Chance Vought brought their design to the competition, the XF4U-1. The Navy was impressed with the design and Vought started on the prototype. During one of the flight tests the XF4U-1 reached a speed of 405 mph and this impressed the Navy enough to order it into production and thus was the beginning for one of the most famous fighter aircraft to come out of WWII.