For helicopters with clockwise rotor rotation, the oppo- site would be true.  contacts a fixed object while hovering sideward, or if the gear is stuck in ice, soft asphalt, or mud. Dynamic rollover may also occur if you do not use the proper landing or takeoff technique or while performing slope operations. Whatever the cause, if the gear or skid becomes a pivot point, dynamic rollover is possible if you do not use the proper corrective technique. Once started, dynamic rollover cannot be stopped by application of opposite cyclic control alone. For exam- ple, the right skid contacts an object and becomes the pivot point while the helicopter starts rolling to the right. Even with full left cyclic applied, the main rotor thrust vector and its moment follows the aircraft as it continues rolling to the right. Quickly applying down collective is the most effective way to stop dynamic rollover from developing. Dynamic rollover can occur in both skid and wheel equipped helicopters, and all types of rotor systems.  When maneuvering with one skid or wheel on the ground, care must be taken to keep the helicopter cyclic control properly trimmed. For example, if a slow take- off is attempted and the cyclic is not positioned and trimmed to account for translating tendency, the critical recovery angle may be exceeded in less than two sec- onds. Control can be maintained if you maintain proper cyclic position and trim, and not allow the helicopter’s roll and pitch rates to become too great. You should fly your helicopter into the air smoothly while keeping movements of pitch, roll, and yaw small, and not allow any untrimmed cyclic pressures. Dynamic rollover is possible even during normal take- offs and landings on relative level ground, if one wheel or skid is on the ground and thrust (lift) is approxi- mately equal to the weight of the helicopter. If the  takeoff or landing is not performed properly, a roll rate could develop around the wheel or skid that is on the ground. When taking off or landing, perform the maneuver smoothly and trim the cyclic so that no pitch or roll movement rates build up, especially the roll rate. If the bank angle starts to increase to an angle of approximately 5 to 8°, and full corrective cyclic does not reduce the angle, the collective should be reduced to diminish the unstable rolling condition. Certain conditions reduce the critical rollover angle, thus increasing the possibility for dynamic rollover and reducing the chance for recovery. The rate of rolling motion is also a consideration, because as the roll rate increases, the critical rollover angle at which recovery is still possible, is reduced. Other critical conditions include operating at high gross weights with thrust (lift) approximately equal to the weight.  Refer to figure 11-6. The following conditions are most critical for helicopters with counter-clockwise rotor rotation: During slope operations, excessive application of cyclic control into the slope, together with excessive collective pitch control, can result in the downslope skid rising  sufficiently to exceed lateral cyclic control limits, and an upslope rolling motion can occur. [Figure 11-7] 11-8 Figure 11-7. Upslope rolling motion.  Figure 11-6. Forces acting on a helicopter with right skid on the ground. SLOPE TAKEOFFS AND LANDINGS NORMAL TAKEOFFS AND LANDINGS CYCLIC TRIM CRITICAL CONDITIONS 4. left yaw inputs. 3. crosswinds from the left. 1. right side skid/wheel down, since translating ten- dency adds to the rollover force. 2. right lateral center of gravity. Pivot Point Bank Angle Weight T i p P a t h P l a n e N e u t r a l C y c l i c T i p P a t h P l a n e F u ll L e ft C y c li c Crosswind T a i l R o t o r T h r u s t MainGLYPH<.notdef> RotorGLYPH<.notdef> Thrust T a i l R o t o r T h r u s t S l o p e Horizontal A r e a o f C r i t i c a l$_{R}$ o l o v e r Full Opposite Cyclic Limit  to Prevent Rolling Motion