 |
|
Glenn
|
|
|
|
Glenn
|
This slide shows what happens when the pilot deflects the spoilers on both wings. Spoilers are small, hinged plates on the top portion of wings. They are used to disrupt or "spoil" the flow of air over a section of a wing.
When the pilot activates the spoilers, the plates flip up into the air stream. The flow over the wing is disturbed by the spoiler, the drag of the wing is increased, and the lift is decreased. Spoilers can be used to "dump" lift and make the airplane descend; or they can be used to slow the airplane down as it prepares to land. When the airplane lands on the runway, the pilot usually brings up the spoilers to kill the lift, keep the plane on the ground, and make the brakes work more efficiently. The friction force between the tires and the runway depends on the "normal" force, which is the weight minus the lift. The lower the lift, the better the brakes work. The additional drag of the spoilers also slows the plane down.
When you travel on an airliner, watch the wings during turns. On some aircraft, the pilot can roll the aircraft using the spoiler on only one wing. You will probably be surprised at how little deflection is necessary to bank (roll) a large airliner. If a plate near the center of the wing comes up, and the wing drops, the pilot is using a spoiler to bank the aircraft. If the rear portion of the wing comes up and the wing drops, the pilot is using an aileron to maneuver.
Go to...
byTom
Benson
Please send suggestions/corrections to: benson@grc.nasa.gov