A-1 Curtiss Model E (Triad) seaplane Renumbered as AH-1. Believed no longer on charge by the time that the second alphanumeric series was instigated. A-2 Curtiss pusher landplane Renumbered as E-1. Contemporary paperwork (dated 27/3/1914) refers to this a/c being renumbered to AH-2, but this is contradicted by all other sources! A-3/4 Curtiss pusher seaplane Renumbered as AH-3 and AH-2. Believed delivered during 1912. A-3 tossed into Anacostia River Jul 31, 1912 when a crosswind caught the plane halfway along the catapult. Pilot uninjured. B-1/3 Wright Model CH seaplane Renumbered as AH-4 to AH-6. Believed that, although number AH-4 was allocated, B-1 was no longer on charge by the time that the second alphanumeric series was instigated. B-2 caused first fatality in US naval aviation when Ens W. D. Billingsley was thrown from pilot seat in turbulent air over Annapolis, MD Jun 20, 1913. Passenger stayed with the plane, sustaining injuries when the plane hit the water. C-1/5 Curtiss F-boat Renumbered as AB-1 to AB-5 Mar 25, 1914. C-2 flew at Hammondsport under complete control of Sperry gyroscopic automatic pilot Aug 30, 2013. There is a photo of AB-3 taken May 12, 1916 of this plane departing the catapult of the armored cruiser USS North Carolina. D-1 Burgess K Renumbered as AB-6, although it is possible that this aircraft was by then no longer on charge. D-2 Burgess H Renumbered as AB-7. E-1 Curtiss OWL Renumbered from A-2 after conversion to amphibian (known as the OWL: Over Water and Land). Later renumbered to AX-1.