Information & Inspiration For
MG Electric Vehicle Enthusiasts
MG Electric Vehicle Enthusiasts
spoilers
In aeronautics, a spoiler (sometimes called a lift spoiler or lift dumper) is a device which increases the drag and decreases the lift of an airfoil in a controlled way. Most often, spoilers are hinged plates on the top surface of a wing that can be extended upward into the airflow to spoil the streamline flow. By so doing, the spoiler creates a controlled stall over the portion of the wing behind it, greatly reducing the lift of that wing section.
Spoilers differ from airbrakes in that airbrakes are designed to increase drag without disrupting the lift distribution across the wing span, while spoilers disrupt the lift distribution as well as increasing drag. However, flight spoilers are routinely referred to as "speed brakes" on transport aircraft by pilots and manufacturers, despite significantly reducing lift.
Spoilers fall into two categories: those that are deployed at controlled angles during flight to increase descent rate ("flight spoilers") or control roll ("spoilerons"), and those that are fully deployed immediately on landing to greatly reduce lift and increase drag ("ground spoilers"). In modern fly-by-wire aircraft, the same set of control surfaces can serve both functions ("multifunction spoilers").
Spoilers were used by most gliders (sailplanes) until the 1960s to control their rate of descent and thus achieve a controlled landing. Since then, spoilers on gliders have almost entirely been replaced by airbrakes, usually of the Schempp-Hirth type. Spoilers and airbrakes enable the glide angle to be altered during the approach while leaving the speed unchanged.
Airliners are commonly fitted with spoilers. Spoilers are used to increase descent rate without increasing speed. Spoilers may also be differentially operated for roll control as spoilerons in place of ailerons; Martin Aircraft was the first company to develop such spoilers in 1948. On landing the spoilers are usually fully deployed to help slow the aircraft: the increase in form drag created by the spoilers provides a braking effect. The spoilers also cause a significant loss of lift so that there is more weight acting on the landing gear, allowing more braking to be used without skidding.
In air-cooled piston engine aircraft, spoilers may be needed to avoid shock cooling the engines. In a descent without spoilers, air speed is increased and the engine will be at low power, producing less heat than normal. The engine may cool too rapidly, resulting in stuck valves, cracked cylinders or other problems. Spoilers alleviate the situation by allowing the aircraft to descend at a desired rate while letting the engine run at a power setting that keeps it from cooling too quickly (especially true for turbocharged piston engines, which generate higher temperatures than normally aspirated engines).
View More On Wikipedia.org
Spoilers differ from airbrakes in that airbrakes are designed to increase drag without disrupting the lift distribution across the wing span, while spoilers disrupt the lift distribution as well as increasing drag. However, flight spoilers are routinely referred to as "speed brakes" on transport aircraft by pilots and manufacturers, despite significantly reducing lift.
Spoilers fall into two categories: those that are deployed at controlled angles during flight to increase descent rate ("flight spoilers") or control roll ("spoilerons"), and those that are fully deployed immediately on landing to greatly reduce lift and increase drag ("ground spoilers"). In modern fly-by-wire aircraft, the same set of control surfaces can serve both functions ("multifunction spoilers").
Spoilers were used by most gliders (sailplanes) until the 1960s to control their rate of descent and thus achieve a controlled landing. Since then, spoilers on gliders have almost entirely been replaced by airbrakes, usually of the Schempp-Hirth type. Spoilers and airbrakes enable the glide angle to be altered during the approach while leaving the speed unchanged.
Airliners are commonly fitted with spoilers. Spoilers are used to increase descent rate without increasing speed. Spoilers may also be differentially operated for roll control as spoilerons in place of ailerons; Martin Aircraft was the first company to develop such spoilers in 1948. On landing the spoilers are usually fully deployed to help slow the aircraft: the increase in form drag created by the spoilers provides a braking effect. The spoilers also cause a significant loss of lift so that there is more weight acting on the landing gear, allowing more braking to be used without skidding.
In air-cooled piston engine aircraft, spoilers may be needed to avoid shock cooling the engines. In a descent without spoilers, air speed is increased and the engine will be at low power, producing less heat than normal. The engine may cool too rapidly, resulting in stuck valves, cracked cylinders or other problems. Spoilers alleviate the situation by allowing the aircraft to descend at a desired rate while letting the engine run at a power setting that keeps it from cooling too quickly (especially true for turbocharged piston engines, which generate higher temperatures than normally aspirated engines).
View More On Wikipedia.org