A-1 Curtiss Model E (Triad) seaplane Renumbered AH-1. Believed no longer on charge by the time that the second alphanumeric series was instigated. A-2 Curtiss pusher landplane Renumbered E-1. Contemporary paperwork (dated 27/3/14) refers to this a/c being renumbered AH-2, but this is contradicted by all other sources! A-3 to A-4 Curtiss pusher seaplanes Renumbered AH-3 and AH-2. Believed delivered during 1912. A-3 tossed into Anacostia River Jul 31, 1912 when a crosswind caught the planne halfway along the catapult. Pilot uninjured. B-1 to B-3 Wright Model CH seaplanes Renumbered 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 avation 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 to C-5 Curtiss F-boats Renumbered AB-1 to AB-5. 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 AB-6, although it is possible that this aircraft was by then no longer on charge. D-2 Burgess H Renumbered AB-7. E-1; A-2 Renumbered after conversion to amphibian (known as the OWL - Over Water and Land)(renumbered AX-1).