Depending on the type of aircraft ailerons may or may not be required to perform a snap roll, but elevator and rudder are the primary controls for this maneuver. Think of a snap roll as a spin occuring along the flight path of the aircraft. Because pattern and F3A aerobatic models tend to have long tail moment arms they are not very good at performing snap rolls compared to short coupled aircraft such as CAPs, Sukhois and Extras. In order to get pattern and F3A aircraft aircraft to perform snap rolls it was found that the use of ailerons was beneficial.

In the official IAC and IMAC judging guide one can read the following:

"In full-scale and IMAC aerobatics the judge must see two things to determine that a snap roll has occurred. The nose must depart the flight path in the correct directions and autorotation must be initiated. If the judge does not observe both events, the figure must be given a zero (0)..."

"For a positive snap roll, the nose must move away from the wheels. This puts the aircraft’s wings near the critical angle-of-attack. Either very shortly after the nose moves, or simultaneously with the nose movement, the aircraft must be seen to yaw around its vertical axis, thus initiating a stall of one wing and subsequent autorotation. If any movement about the longitudinal (roll) axis is observed before the nose departs the line of flight, the figure is downgraded..."

"Snap rolls must be observed very carefully to ensure that the competitor is not “aileroning” the aircraft around its longitudinal axis. Aerobatic aircraft with very high rates of roll can occasionally fool a judge in the execution of snap rolls. The movement of the aircraft’s nose departing the flight path prior to autorotation is a good clue to the proper execution of snap rolls."