Working exclusively on the aircraft and closely with Lindbergh, the staff completed the Spirit of St. Louis 60 days after Lindbergh arrived in San Diego. Powered by a Wright Whirlwind J-5C 223-hp radial engine, it had a 14 m (46-foot) wingspan, 3 m (10 ft) longer than the M-1, to accommodate the heavy load of 1,610 L (425 gal) of fuel. In his 1927 book We, Lindbergh acknowledged the builders' achievement with a photograph captioned "The Men Who Made the Plane", identifying: "B. Franklin Mahoney, president, Ryan Airlines", Bowlus, Hall and Edwards standing with the aviator in front of the completed aircraft.[4]