 |
Answer :
A snap roll is an autorotational roll, sort of a spin on a horizontal axis. If you think of an aileron roll where the airplane rotates 360 degrees along its longitudinal axis, a snap roll is a stalled aileron roll which rotates very quickly. In a snap roll there is a brisk rate of change in pitch and yaw, with abrubt control inputs giving it a high acceleration rate. This also means that in a snap roll there are more G forces than in a simple aileron roll.
To do a snap roll, it is important to establish a proper entry speed for your particular airplane so that you don't "over G" or "over stress" it. The pilot pulls the stick back to "break" the airplane into the stall while applying rudder in the direction of the snap roll. The airplane accelerates very quickly and while snap rolling, the pilot needs to relax back pressure slightly in order to help accelerate the roll. To recover the stall is "broken" by pushing the stick forward and neutralizing rudder. Sometimes in a series of multiple snap rolls the pilot must "help" the airplane stay in the snap roll by "loading and unloading" the control stick.
Other than a rhythmic rolling turn, I think the snap roll is the hardest maneuver to perfect for the competition pilot. They are often done on a vertical, descending or ascending line as well as on the horizontal and each attitude requires a slightly different technique to get the best snap roll. Also, each airplane - Decathalon, Extra, Sukhoi, etc. - requires slightly different control inputs to get the best snap roll.
The snap roll is a maneuver that the pilot can never practice enough or do well enough consistently!
Patty Wagstaff
Air Show Performer
Aerobatic Champion |
1001 Aviation Photos | Ask the Expert | This Day in Aviation | Airplane of the Month
Privacy Policy 