The spoiler surfaces are used to prevent lift when the aircraft is on the ground, to decrease lift in the air, for ground lift dumping, to supply roll control, and for speed braking. The spoilers include the ground spoilers and the multi-function spoilers. Four spoilers are installed on the top trailing edge of each wing.

The ground spoilers are used to supply ground lift dumping when the aircraft touches the ground or during a rejected takeoff. Two ground spoilers are installed on the top surface of the trailing edge of each wing above the flap. The inboard and outboard spoilers are found inboard of the multi-function spoilers. Each ground spoiler includes a phenolic sheet, four hinge fittings, one actuator hinge fitting, and a honeycomb core. The top and bottom skin panels, made from graphite laminations, are the covers for the honeycomb core of the ground spoilers. The phenolic sheet is installed below the attachment area of the actuator hinge fitting to have sufficient strength for the fastener installation. The ground spoilers are identical in design but are not interchangeable for position.

Ground Spoiler Hinge-Fittings

The inboard and outboard ground spoilers are attached to the rear spar of the outer wing. The inboard actuator fitting is attached to the rear spar between the No. 2 and No. 3 hinge fittings. The outboard actuator fitting is attached to the rear spar between the No. 6 and No. 7 hinge fittings.

All the fittings are made from machined aluminum alloy. Each hinge fitting has two bushings installed at the hinge pivot points. Each actuator fitting has two bushings.

The multi-function spoilers help the ailerons to control roll, especially during crosswind landings. They are also used as an alternative to the ailerons if the ailerons do not operate correctly. The multi-function spoilers can also be symmetrically controlled by the pilot, to be used as the speed brakes, through the flight-spoiler control lever. The spoilers supply ground lift dumping when the aircraft is on the ground; they are automatically retracted/extended at the same time as the ground spoilers.

Two multi-function spoilers are installed on the top surface of the trailing edge of each wing above the flap. The inboard and outboard multi-function spoilers are found outboard of the ground spoilers. The inboard multi-function spoiler includes a phenolic sheet, four hinge fittings, an actuator hinge fitting, and a honeycomb core. The top and bottom skin panels, made from graphite laminations, are the covers for the honeycomb core of the multi-function spoilers. The phenolic sheet is installed below the attachment area of the actuator hinge fitting to have sufficient strength for the fastener installation.

The outboard multi-function spoiler includes a panel, a wedge, four hinge fittings, and an actuator hinge fitting. The panel is made from machined aluminum alloy. The wedge is installed on the trailing edge area of the spoiler.

Multi-Function Spoiler Hinge-Fittings

The inboard and outboard multi-function spoilers are attached to the rear spar of the outer wing. The inboard actuator fitting is attached to the rear spar between the No. 10 and No. 11 hinge fittings. The outboard actuator fitting is attached to the rear spar between the No. 14 and No. 15 hinge fittings.

The middle hinge fittings and actuator hinge fitting on the outboard multi-function spoiler are machined from aluminum alloy with the spoiler panel. The middle hinge fittings, the actuator hinge fittings and the spoiler panel are made as one full structure.

The other fittings are made from machined aluminum alloy and installed to each multi-function spoiler.

Each hinge fitting has a bushing installed at the hinge pivot points. Each actuator fitting has a bushing installed.

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