Grumman FF/SF And G-23 Delfin/Goblin and Prototypes

The Grumman FF-1 and its derivatives, namely the SF-1 and G-23, represent a paradox in naval aircraft design. On one hand, it represented the end of the line for two-seat US Navy fighters in the biplane era. On the other hand, it incorporated relatively new technologies that when brought together, gave the FF-1 a significant performance margin over existing U.S. Navy fighters. Indeed, design choices such as retractable landing gear, enclosed cockpits and all-aluminum construction existed previously, but the FF-1 incorporated all these technologies into a single airframe. In the Navy's own words, "The design of the XFF-1 marked a considerable advance in the reduction of weight and drag for this class of airplane and resulted in correspondingly high performance." 

The origins of the FF-1 can be traced back to early 1930, just months after the Grumman Aircraft Engineering Corporation filed articles of incorporation. During discussions with the Navy’s Bureau of Aeronautics regarding their “A” Float, the Navy became intrigued by Grumman’s approach to retractable landing gear, the Navy asked Grumman about the feasibility of adapting their patented landing gear system to existing Navy fighters, such as the Boeing F4B and the Curtiss F8C. Grumman advised against this approach stating that adding retractable landing gear to these existing aircraft would force a complete redesign. Furthermore, being an aircraft manufacturing company, Grumman desired to design and build its own aircraft. Grumman’s Design G-5, was submitted to the Navy, and in March 1931, a contract was awarded to Grumman for the XFF-1. 

Naval Fighter Series NF121 is an in-depth study of the design and development of the FF-1 and its derivatives. The first half of the book describes the XFF-1, FF-1, XSF-1, SF-1, XSF-2, GG-1 and XSBF-1 in detail with photographs and drawings, while the second half of this book covers operational use. While U.S. Navy service was limited to two fleet squadrons, the FF-1 and SF-1 enjoyed long careers in Navy and Marine Corps Reserve squadrons until mid-1942.

Perhaps the most interesting aspect of this series was the G-23, a license-built derivative manufactured by Canadian Car & Foundry in Fort William, Ontario, Canada. A total of 52 G-23s were built, with 34 finding their way into combat use by Republican forces during the Spanish Civil War. The Spanish “Delfin”, as it was known saw extended service after the war, with the last one being retired in early 1954, nearly 22 years after the first flight of the XFF-1. 15 G-23s were accepted by the Royal Canadian Air Force in 1940 as the “Goblin”, and their service is also included in this book.

132 pages (128 B&W, plus 4 color Pages), 363 photos and drawings