Now we use engine-bleed air-thrusters on the wings for roll control.

In fact, few early aircraft had sufficiently precise roll control to have performed this maneuver properly.

In production models after 1981 the ailerons were replaced with spoilers for roll control.

The 1923 model was demonstrated at speeds up to 40 mph with poor roll control.

On modern aircraft, which have the benefit of automation, they can be used in combination with the ailerons to provide roll control.

This results in a large speed range and good handling characteristics in turbulence, without heavy roll control.

The wings were of unequal span, and employed wing-warping for roll control.

Winglets had been added to the aircraft that improved roll control at all speeds, especially in the stall.

Single seat model with ailerons used for roll control, a shorter wing and flaps.

Part span flaps are provided at the trailing edge of the wings for roll control.