wing sweep increases, reducing drag. This change in the drag distribution creates a restoring moment. Control. A way to get yaw control is to use differential air braking to affect the drag directly. This technique is suited to Electronic flight controls, as on the Northrop Grumman B-2 flying wing. Combined longitudinal–directional stabilizers On some aircraft, horizontal and vertical stabilizers are combined in a pair of surfaces named V-tail. In this arrangement, two stabilizers (fins and rudders) are mounted at 90–120° to each other, giving a larger horizontal projected area than vertical one as in the majority of conventional tails. The moving control surfaces are then named ruddervators.A portmanteau of rudder & elevator The V-tail thus acts as both a yaw and a pitch stabilizer. Although it may seem that the V-tail configuration can result in a significant reduction of the tail wetted area, it suffers from an increase in control-actuation complexity, as well as complex and detrimental aerodynamic interaction between the two surfaces. This often results in an upsizing in the total area that reduces or negates the original benefit. The Beechcraft Bonanza light aircraft was originally designed with a V-tail. Others combined layouts exist. The General Atomics MQ-1 Predator unmanned aircraft has an inverted V-tail. The tail surfaces of the Lockheed XFV could be described as a V-tail with surfaces that extended through the fuselage to the opposite side. The LearAvia Lear Fan had a Y-tail''. All twin tail arrangements with a tail dihedral angle will provide a combination of longitudinal and directional stabilization. Notes References External links Aircraft-related terminology Aircraft controls