When American pilots first encountered the Zero, they were stunned. The Zero had nearly complete initial dominance. This dominance is sometimes attributed to the A6M’s high speed. In reality, however, the Zero was rather modest in straight-line speed, with a maximum speed for the A6M2 Model 21 of about 317 mph to 332 mph at the critical altitude of about 16,000 feet. In addition, the Zero was not very good in dives and had severe maneuverability limitations at speeds above about 180 mph. The Zero’s great strengths were really its maneuverability at moderate speed, its incredible combat range, (arguably) its cannon armament, and, at the start of the war with the United States, its combat-experienced pilots.
Rated Speeds in General
For aircraft, the “top speed” is measured at the aircraft’s “critical altitude”—the altitude at which level speed is maximum at full military...