The R-22 Spearhead starfighter, alternatively referred to as the Tammuz-an R-22 Spearhead fighter and commonly known as the "A-wing," represented a cutting-edge starfighter prototype. This advanced craft was engineered by the Tammuz-an species to serve as an escort fighter for their space navy. The design, drawing inspiration from the Aurek-class tactical strikefighter, was later replicated by Alliance Underground Engineering and Incom Corporation during the development of the RZ-1 A-wing interceptor. The RZ-1 A-wing interceptor is considered an evolved form of both the R-22 Spearhead and the Delta-7 Aethersprite-class light interceptor.
The R-22 Spearhead starfighter was a state-of-the-art, highly maneuverable craft. Its design was influenced by the Aurek-class tactical strikefighter, a starfighter model produced by Republic Fleet Systems that served as the Galactic Republic's standard "hyperspace snub" fighter for close to four millennia (years). Similar to the Aurek, the R-22's frame in space was said to resemble the letter A from the High Galactic alphabet, which led to its informal "A-wing" nickname. It gained popularity among pilots who enjoyed modifying their ships, often enhancing the R-22's flight capabilities and removing any non-essential components to further boost its speed and agility.
The Tammuz-an, a species of tall humanoids native to a planet of the same name, developed the R-22 Spearhead. Their space navy utilized it as an escort for the Tammuz-an shipping fleet.
Shortly before the Battle of Yavin, the R-22 Spearhead, known as the "A-wing," became an experimental platform for the Rebel Alliance. In one of its initial operational tests, the Rebels deployed a single R-22 to attack an undefended Imperial repair facility. The fighter performed exceptionally well, successfully destroying the facility before the Nebulon-B frigate Virulence could react. This mission was later adapted into a training simulation for new pilots.
Around that time, the Alliance Fleet began deploying a number of R-22s. Captain Juno Eclipse and PROXY utilized a two-seater R-22 to travel to Dac in order to assist Admiral Gial Ackbar and Senator Bail Organa in liberating the Mon Calamari and enlisting them into the Alliance. The fleet employed them in the Assault on Kamino against the Imperial TIE/sa bombers. Keyan Farlander piloted Spearheads in multiple missions during Operation Skyhook, and at least a pair of R-22s were involved in the Battle of Yavin, with one being flown by Jake Farrell.
"A-wing" became the informal name for the Spearhead among Rebel pilots. This name stuck when General Jan Dodonna and Walex Blissex modified the model following the Battle of Yavin, resulting in the Rebel Alliance's rapid RZ-1 A-wing interceptor.
Dodonna's decision to develop the RZ-1 was primarily motivated by the Alliance's need for a starfighter that could compete with the TIE/LN starfighter's inherent speed. Furthermore, the RZ-1 was recognized for its enhanced maneuverability compared to the Spearhead, suggesting that the engine design was the most significant difference between the two aircraft.
The weapons systems may have also undergone similar modifications, as early Spearheads utilized green laser ammunition, unlike the red/orange ammunition typically used by Alliance fighters.
While the majority of sources indicated that the Rebel Alliance introduced the A-wing after the Battle of Yavin, some Expanded Universe sources presented conflicting information, depicting A-wings in use before Yavin. Examples include Star Wars: Droids, Star Wars: X-Wing, Star Wars: Rebel Assault, Star Wars: Force Commander, and Star Wars: Empire at War. This discrepancy was ultimately reconciled in C-3PO: Tales of the Golden Droid, which introduced the R-22 Spearhead to account for the pre-Yavin appearances of A-wings.