An alternative to manual control is an automatic system that matches aileron deflection to bank angle. This can be done indirectly, and inexpensively, with a rate gyro that senses the yaw rate of the model. There are two basic types of gyroscopes. These are expensive and not commonly available for models. These are commonly available, and inexpensive.
Most gyros have only a single axis about which they are sensitive.
For instance, if the axis is mounted vertically, then it will be sensitive to yaw, but insensitive to pitch and roll. It is also possible to mount the gyro at an angle so that it has sensitivity in two airplane axes, at somewhat reduced amounts. Model gyros are placed in-line between the radio receiver and the servo to be controlled. The gyro input is roughly proportional to the rate at which the gyro is rotated. Some gyros also automatically adjust their gain according to the manual signal deflection.