Passage: The United States Navy (USN) hoped to use the V-1710 in its rigid airships USS Akron (ZRS-4) and USS Macon (ZRS-5), but both were equipped with German-built Maybach VL-2 engines as the V-1710 was still in testing when the Macon was lost in February 1935 (the Akron having been lost in April 1933). The USAAC purchased its first V-1710 in December 1932. The Great Depression slowed development, and it was not until December 14, 1936 that the engine next flew in the Consolidated XA-11A testbed. The V-1710-C6 successfully completed the USAAC 150 hour Type certificate on April 23, 1937 at , the first engine of any type to do so. The engine was then offered to aircraft manufacturers where it powered the prototype Curtiss XP-37s. All entrants in the new pursuit competition were designed around it, powering the Lockheed P-38, Bell P-39 and Curtiss P-40. When war British Purchasing Commission asked North American Aviation to build the P-40 under license, NAA instead proposed their own improved aircraft design, using the V-1710 in their North American P-51 Mustang.
How many airships did the United States Navy (USN) hope to use the V-1710 in? How many months after being flown in the testbed did the V-1710-C6 successfully completed the USAAC 150 hour Type certificate? How many months after the USAAC purchased its first V-1710 was the Akron lost? How many types of aircraft was the engine used in? How many years after acquiring the V-1710 was the engine next flown in the Consolidated XA-11A testbed? How many years after the Akron was lost was the Macon lost? Which airship was lost later, the Akron or the Macon? Which was lost first, the Macon or the Akron?