Spoilers are hinged plates on the top surface of a wing, hinged along their leading edges and able to reach a maximum deployment of 50 degrees. When raised, they interfere with the smooth flow of air and thereby decrease lift while simultaneously adding drag. During flight, the increased drag and decreased lift are utilized for braking, speed reduction, and a steeper descent. On touchdown, the panels dump lift and act as airbrakes, bringing weight onto the wheels and shortening the landing run. Select units can be deflected differentially to assist ailerons in roll control, so the assembly serves both as a flight maneuver device and a ground stopping aid.
Expert behind this article
Jim Goodrich
Jim Goodrich is a pilot, aviation expert and founder of Tsunami Air.
What are aircraft spoilers?
Aircraft spoilers are the large panels along the top or upper surface of each wing. They counteract the lift that the wings are still generating the moment the wheels touch the ground. Flight spoilers are routinely referred to as "speed brakes" on transport aircraft by pilots and manufacturers.
Spoilers are flat panels on the upper surface of an airplane wing, installed flush and approximately parallel to the lateral axis. These hinged plates, located forward of the flaps, raise up like an upside-down split-flap and are standard equipment on gliders.
A spoiler is a multifunctional flight control surface that increases drag and decreases lift of an airfoil in a controlled way. It spoils streamline flow so that lift decreases and the aircraft descends without gaining excessive speed. Because loss of lift results in higher stall speed, pilots use them judiciously while still achieving precise flight-path control.
On transport aircraft, the same panels are called speed brakes, and they can be deployed manually by the pilot or extend automatically under certain circumstances. During final approach to touchdown they help manage energy, and after landing they act as lift dumpers, pressing the airplane firmly onto the runway for maximum braking effectiveness.
A spoiler on an airplane is an upward-moving panel mounted on the wing. Its main purpose is to interrupt the even airflow over the wing to decrease lift and add drag. I see this control surface's part in disrupting the streamlined airflow useful, for it gives the aviator better control over the aircraft. Spoilers give important aid, particularly on bigger aircraft, during the stages of descent and touchdown.
Jim GoodrichPilot, Airplane Broker and Founder of Tsunami Air
What is the purpose of airplane spoilers?
Spoilers are secondary flight-control surfaces whose chief duty is to dump lift and add drag. Outboard or mid-section panels work with, or even replace, ailerons: when the flight deck commands a roll, the spoiler on the descending wing rises, disrupts flow over that wing section, destroys some lift and generates form drag, while the opposite wing retains its lift; the imbalance rolls the aircraft. Inboard panels act symmetrically as speedbrakes; by spoiling lift and increasing form drag they let the aircraft descend steeply without accelerating, giving the pilot glide-path control on final approach.
On the ground the same panels re-label themselves as ground spoilers. The instant the wheels touch, automatic extension spoils most of the wing's remaining lift, forcing the full weight of the aircraft onto the landing gear. With lift eliminated, tyre friction rises and the wheel brakes work at maximum efficiency, shortening the landing roll and preventing the airplane from bouncing.
Airplane spoilers blocking seam the airflow over airfoils. This interruption lessens lift and lets the aircraft go down quickly. After touchdown, spoilers expand to hinder lift fully, so the plane no longer floats and the burden moves onto wheels. With lift discarded, the plane trusts harder on reverse propulsion and wheel brakes, shortening the landing roll and keeping good velocity control on the airstrip.
How do airplane spoilers work?
Spoilers work by disrupting airflow and reducing lift. Spoilers are panels on the wing with each panel hinged and mounted on the upper surface. Spoilers are commanded by flight control computers that extend the panels upward into the airflow. When spoilers rise upward into the airflow they deliberately spoil the smooth passage of air so that lift is decreased and the reduction in lift makes aircraft descend at faster rate. At takeoff roll spoilers droop then go inline with flaps and wings, giving extra camber for lift. After touchdown the same panels re-extend so that speedbrakes are used after landing.
Airplane spoilers work by deliberately ruining the lift that keeps the aircraft aloft. When aviators command these surfaces, they interrupt the fine airflow over the airfoil, so the jet can descend or roll. Deployment is synchronized with ailerons and other control surfaces, assuring the aircraft stays steady during pivotal stages of flight.
