The production version of the XA-1, with a tail gun and several other improvements added.
About this creation
The Zephyrian A-1, which would come to be nicknamed the "Falcon", was Zephyros' first dedicated divebomber, developed at the start of the war with Esthen, and ended up being a very innovative aircraft. It was rushed to pre-production and thus suffered many teething problems; namely, aside from the notoriously unreliable early-model R2 Radial that powered the aircraft, the A-1 was also designed without a tailwheel--both forcing a detachable dolly to be used for actual strike missions, as it turned out that the MB1 bomb, which had been designed for the A-1, required greater ground clearance--and causing severe damage to the tail during landing.
Field modifications began to attach materials to the bottom of the tail to provide sufficient clearance, and the YA-1s in testing service had a conversion kit to attach a small metal ridge to the end of the tail--along with ballast to rebalance the aircraft--and both these and the initial production order, which had this adjustment built into them, were designated A-1A.
Shortly after the fielding of the A-1A, development of an improved variant began: The A-1B. The A-1B was designed to fix the many problems of the YA-1 and A-1A.
The A-1B replaced the metal ridge with a proper tailwheel, akin to that mounted on the then-contemporary P-4 Hawk, and added proper "spats", or "pants", to the main landing gear wheels, making the A-1B more aerodynamic.
The A-1B's most notable feature was that its landing flaps were perforated, to double as dive brakes; this allowed the A-1B to dive faster at steeper angles, and was lacking on even the more-modern Misawa FB. 1 and FB. 2. This was what earned the A-1 its "falcon" moniker, after the peregrine falcon, due to its then-unprecedented diving abilities.
A notable development of the Falcon was the SBN, sometimes nicknamed the "Sea Falcon", originally designated SBX ("Scout Bomber eXperimental") prior to the privatization of Zephyros' aircraft manufacture. The SBN was instrumental in pushing Esthen back, as it was Zephyros' first carrier-capable divebomber, and thus the first major thorn in the Esthen Navy's side. Due to the teething problems with early-model A-1s, the SBN was developed directly from the A-1B.
Unlike the A-1B, the SBN-1 had a three-bladed propeller installed, slightly improving on its performance.
The SBN's major innovation was that it was itself the first aircraft of its era with a deployable arrestor hook--when released, a series of latches would close after the arrestor hook fell via gravity; a far cry from the pressure-based systems often used in fully-retractable arrestor hooks, this design had to be manually folded in by deck crews after the SBN landed.
See Also Aircraft of comparable role, configuration, and era