SPOILER CONTROL SYSTEM.pdf

GULFSTREAM G650ER SYSTEM DESCRIPTION MANUAL SPOILER CONTROL SYSTEM — SYSTEM DESCRIPTION 1. General A. Description The spoiler control system provides electrical and mechanical control of the spoilers, fault monitoring and annunciation. Spoilers are used for different flight control functions. Spoile...

GULFSTREAM G650ER SYSTEM DESCRIPTION MANUAL SPOILER CONTROL SYSTEM — SYSTEM DESCRIPTION 1. General A. Description The spoiler control system provides electrical and mechanical control of the spoilers, fault monitoring and annunciation. Spoilers are used for different flight control functions. Spoilers assist the ailerons in roll control and also provide speed brake and ground spoiler functions. The spoiler system is part of the primary flight control system. Three separate spoilers (inboard, midboard and outboard) are located above the flaps on each wing. See Figure 1. Spoiler surface movements are primarily controlled by the Flight Control Computers (FCCs). The FCCs transmit command information to the Remote Electronic Units (REUs) located at each actuator. The FCCs receive status, health and validity information from the spoiler actuation system. Data to and from the REUs is sent using Bidirectional ARINC 429 (BD429) buses. The FCCs transmit the data received from the REUs to the modular avionics units. The Backup Flight Control Unit (BFCU) commands only the outboard spoilers for the spoiler function. The BFCU receives inputs only from the control wheel position RVDTs and transmits command information on digital data busses to the outboard spoiler REUs. The BFCU commands are ignored unless there has been a total failure of both FCCs. Spoiler deflection is determined by the specific task and flight conditions. 2. Subsystems The spoiler control system has the following subsystems: Spoiler Interface and Control, 27-61-00, System Description Spoiler Actuation, 27-63-00, System Description Spoiler System Electronics, 27-65-00, System Description 3. Subsystem Details A. Spoiler Interface and Control The spoiler RVDT position sensorssupply input to the FCCs and are located in the following two areas: The pilot and copilot control modules The speed brake control module Conventional pilot / copilot control wheel / column assemblies move the RVDT position sensors in the control module assemblies. The speed brake control module is located on the pedestal and contains the handle and four RVDT position sensors. The speed brake handle is manually controlled. (1) Ground Spoiler Ground spoiler deployment is controlled by the FCCs. Automatic deployment of the ground spoilers occurs at landing touchdown or after an aborted takeoff, provided the ground spoiler deployment conditions are satisfied. The two primary pilot inputs for ground spoiler deployment are as follows: Throttle at idle Ground spoiler switch ARMED Additionally, the FCC looks at combinations of indications to determine if the appropriate conditions are met for ground spoiler deployment from the following sensors: 27-60-00 Page 1 August 15/14 GULFSTREAM G650ER SYSTEM DESCRIPTION MANUAL Main landing gear WOW Wheel speed Radio altimeter The ground spoiler function is the automatic deployment of all six spoilers to reduce roll out and braking distance. During deployment, the spoilers are extended to their maximum angular deflection of 55°. The ground spoiler (GND SPOILER) and ground spoiler flap override (GPWS / GND SPLR FLAP ORIDE) switches are located on the pedestal switch panel. The GND SPOILER armed switch is a split lens with the upper portion labeled OFF (amber) and the lower portion labeled ARMED (blue). When the switch is extended, OFF lights up and when depressed ARMED lights up. The OFF annunciation is extinguished when the landing gear is retracted. These switches serve two functions. The primary function allows the flightcrew to inhibit certain EGPWS aural warnings that occur when the aircraft is at lower altitudes with flaps not set to a landing configuration. This is calculated by the EGPWS system based on the flight conditions and local terrain. The secondary function is to allow use of wheel speed logic in the automatic ground spoiler deployment when the flap setting is 20° or less. (2) Flight Spoiler Flight spoiler deployment is controlled by the FCCs. Flight spoilers use the midboard and outboard spoilers for roll augmentation. The two panels on the downward moving wing are extended to assist the ailerons with roll. Flight spoiler commands are derived from the same control wheel RVDT sensor inputs to the FCC that command the ailerons. The amount of spoiler deflection is determined by the particular flight conditions and the commanded rate of roll. The FCC control law determines the required spoiler angular deflection for any particular turn, with 55° being the maximum. (3) Speed Brake The speed brake function is manually controlled using the speed brake handle on the pedestal. The speed brake uses all six spoilers in flight to provide an air brake, decrease lift and increase drag. Typically speed brakes are used to slow down and increase the rate of descent. With speed brakes extended, spoilers on the downward moving wing are extended farther than those on the upward moving wing. To ensure adequate roll performance when the speed brakes are deployed, a mixing law for simultaneous roll and speed brake commands is implemented. Speed brake deployment is symmetrical between left and right wings and proportional to speed brake handle movement, with maximum spoiler angles specified at 30°. B. Spoiler Actuation Hydraulic actuation is driven by FCCs. The FCCs provide position signals to the REUs. The REUs process the signals to drive hydraulic manifold that initiate actuator movement to control spoiler movement. The left and right hydraulic systems provide hydraulic power to the actuator control manifolds. Electrically controlled hydraulic actuators provide power for spoiler movements. Each spoiler is controlled by a single actuator. There are a total of six actuators, as follows: Outboard spoilers use EBHA actuators Inboard and midboard spoilers use EHSA actuators The EBHA has a dual power source, hydraulic and electric. The EBHA is comprised of an hydraulic cylinder / piston assembly and the following two hydraulic manifolds: HA and EB. The EBHA 27-60-00 Page 2 August 15/14 GULFSTREAM G650ER SYSTEM DESCRIPTION MANUAL consists of an hydraulic part, EHSA like, complimented with local Motor Control Electronics (MCEs) to drive the hydraulic cylinder / piston in backup mode. The REU in the EBHA system is mounted directly to the hydraulic actuator manifold. The MCE is mounted directly to the electrical backup hydraulic manifold. The associated actuator is located between the hydraulic actuator manifold and the electrical backup manifold. If the mode select valve is de-energized or one of the outboard spoiler REUs fails, the EBHA enters power retract mode. This mode functions similar to electrical backup where the electric motor runs as required to hold the spoiler in its retracted state. C. Spoiler System Electronics Pilot and copilot control wheels provide control inputs for flight control surface movement using RVDT position sensors. The sensors provide data to the FCCs and the BFCU. The FCCs and BFCU send control data to REUs located at each actuator. The REUs control the hydraulic actuators that power spoiler movement. The FCCs receive inputs from various aircraft systems and switches, including the following: Control wheel position RVDTs Speed brake handle RVDTs Spoiler ARM switch Flap override switch Each FCC transmits four separate BD429 buses to the spoiler REUs. This provides a total of eight independent FCC buses for spoiler control. In addition, the BFCU provides two separate standard ARINC 429 (A429) buses, one bus for each outboard spoiler EBHA REU. The spoiler EHSA REUs do not receive an input from the BFCU. Each FCC has a single MCE A429 transmit bus. If both outboard flight spoiler REUs fail, the MCE bus allows the FCCs to retain control of the surface by directly commanding the MCE. Normally the MCE is controlled directly by its associated EBHA REU. When the actuator is in the electrical backup mode, the MCE controls the EBHA motor. 4. Operational Summary A. Spoiler Control System Spoiler movements are primarily controlled by the FCCs. The FCCs transmit command information on BD429 digital data buses to the REUs located at each actuator. The REUs command the hydraulic actuators to move the spoilers. The REUs provide position loop closure and actuator monitoring. For integrity control, the REU has two dissimilar hardware lanes, one for command and one for monitoring. The GND SPOILER armed switch is the primary flightcrew control for system operation. For automatic ground spoiler deployment, the switch is placed in the ARMED position. The GND SPOILER switch is located on the pedestal switch panel. 27-60-00 Page 3 August 15/14