He was voiced by the late June Foray, and later by Tara Strong.
Rocky's personality was meant to be that of an upstanding, if slightly naive, all-American youth. As the brains of the "moose and squirrel" duo, Rocky often was shown as coming up with creative solutions to the various situations the duo found themselves in on their adventures. However, he is no less gullible toward Boris Badenov's and Natasha Fatale's disguises than Bullwinkle. The best he can do is to occasionally remark, "Those two look familiar!" or "That voice, where have I heard that voice?"
Powers and abilities
Rocky often made extensive use of his ability to fly, which was presented with, appropriate to his full name, a jet engine sound effect. The original opening title of Rocky and His Friends introduces Rocky as "that Jet Age aerial ace", complete with Rocky performing a solo air show for a crowd of spectators. His airborne abilities have been depicted inconsistently; some episodes, such as the first season's "Jet Fuel Formula" storyline, presented this ability as limited to gliding (similar to the abilities of a real flying squirrel). Other episodes presented Rocky's flight abilities as similar to those of Superman (hovering in mid-air, ascending in altitude, carrying objects, etc.); one example is Rocky flying from Minnesota to District of Columbia under his own power in the second season's "Greenpernt Oogle" storyline.
Occasionally, Rocky would rely on Bullwinkle's strength (via an acrobatic maneuver) to provide him with an extra boost in flight speed, as shown in his attempt to reach the hovering Mount Flatten in the second season's "Upsidaisium" storyline.
According to the series, Rocky learned his aerial skills at the Cedar Yorpantz Flying School (a play on the idiomatic expression "seat of your pants").