Elsewhere

    In October 1928, contracts for the construction of two 6.5 million cubic feet, rigid airships (ZRS-4 Akron and ZRS-5 Macon) were issued by the Navy to the Goodyear Zeppelin Corporation of Akron, Ohio. With these design approvals for an airship 785 feet long with a range of over 9,000 miles, the Navy entered into another realm of flight - the use of dirigibles as airborne versions of aircraft carriers that could launch, recover and hangar five aircraft while airborne by means of a retractable trapeze extending below the airship to which they could hook up. Of three aircraft designs submitted for consideration, only the Curtiss XF9C-1 was small enough to fit through the airship's arbitrarily designed hangar door. Following conventional testing, it was fitted with a sky hook and made its first hook-on to an experimental trapeze on the USS Los Angeles in October 1931.
    Following major design changes, six production models of the XF9C-2 prototype were ordered and designated as F9C-2 "Sparrowhawks". All six were delivered in September 1932 and began operating as scouts from the Akron which was lost a year later with no F9C-2s on board. Flying continued from the Macon until she too was lost along with four Sparrowhawks. In the course of flying trials, landing gear were removed once the aircraft were aboard the airship, depending thereafter upon their sky hooks for launch and recovery. Landing gear were reinstalled before aircraft left the airship to return to their home base.  After the loss of the Macon, the two surviving F9C-2s and the XF9C-2 remained in service for a year or two as utility aircraft, and were ultimately cannibalized to create the only F9C-2 Sparrowhawk in existence today (BuNo 9056). It is on loan from the National Air and Space Museum.