AILERON INTERFACE AND CONTROL.pdf

GULFSTREAM G650ER SYSTEM DESCRIPTION MANUAL AILERON INTERFACE AND CONTROL — SYSTEM DESCRIPTION 1. General A. Description NOTE: The following paragraphs are used in conjunction with Figure 1, Figure 2, Figure 3, Figure 4 and Figure 5. The aileron interface and control system provides electrical and m...

GULFSTREAM G650ER SYSTEM DESCRIPTION MANUAL AILERON INTERFACE AND CONTROL — SYSTEM DESCRIPTION 1. General A. Description NOTE: The following paragraphs are used in conjunction with Figure 1, Figure 2, Figure 3, Figure 4 and Figure 5. The aileron interface and control system provides electrical and mechanical control of the ailerons and spoilers, fault monitoring and annunciation. Conventional control wheels are used by the flightcrew to control aircraft roll. The aileron system is part of the primary flight control system, which is an integrated three axis Fly-By-Wire (FBW) system that provides the following control: Roll control through the aileron control system. See Aileron Control, 27-10-00, System Description. The roll control function is supported by the spoiler control system. See Spoiler Control System, 27-60-00, System Description Pitch control through the elevator control system. See Elevator Control, 27-30-00, System Description. The pitch control function is supported by the horizontal stabilizer control system. See Horizontal Stabilizer Control, 27-40-00, System Description Yaw control through the rudder control system. See Rudder Control, 27-20-00, System Description The pilot and copilot control wheels are mechanically linked during normal operation so they always move together. If a jam occurs with one of the control wheels, either pilot may override the other by exceeding and maintaining the breakaway force. Each control wheel is connected by control cables to its associated pilot and copilot aileron and elevator control module, located below the cockpit floor. Aircraft roll control is accomplished through aileron surfaces on the outboard rear beam left and right wing. Electrically controlled hydraulic actuators provide power for aileron surface movement. Pilot and copilot control wheels provide the control inputs through RVDT position sensors. See Aileron Cockpit Sensors, 27-12-00, System Description for more details. The commanded position data is provided to the two Flight Control Computers (FCCs) and the Backup Flight Control Unit (BFCU). The computers transmit the data on digital data buses to the Remote Electronic Units (REUs) located at each actuator. The REUs command the hydraulic actuators that move the aileron surfaces. NOTE: The BFCU commands are ignored by the REUs unless there is a total failure of both FCCs. 2. Component Location COMPONENT ATA QTY PER A/C LOCATION Aileron control wheel 27-11-01 2 Cockpit Cockpit flight control cable 27-11-03 2 Control column, extending under cockpit floor to aileron and elevator control module Cockpit flight control cable retaining pin 27-11-05 2 Aileron and elevator control module, on aileron sector below aileron RVDT Aileron control cable pulley 27-11-07 2 Aft of control column, below cockpit floor 27-11-00 Page 1 August 15/14 GULFSTREAM G650ER SYSTEM DESCRIPTION MANUAL COMPONENT ATA QTY PER A/C LOCATION Aileron control override pushrod 27-11-09 2 Forward side of aileron and elevator control modules Aileron 27-11-11 2 Wing rear beam Aileron trim interconnect pushrod 27-11-13 1 Lower rod, aft of aileron and elevator control modules Aileron trim centering bungee 27-11-15 1 Lower aft on copilot aileron and elevator control module 3. Component Details A. Aileron Control Wheel The pilot and copilot control wheel assembly is part of the wheel / column assembly. The control wheel is located at the top of the control column. The wheel provides a mechanical interface to the pitch and roll control modules. The control wheel travel is ±60° and is limited by over travel mechanical stops in the roll control module. The control wheel allows the pilot or copilot to control roll by turning the control wheel in the direction of desired roll (counterclockwise to roll left, clockwise to roll right). The FBW system has artificial feel design for human factors operation. Dampers provide smooth operation and alleviate oscillations. A control column head universal joint connects the control column to the control column torque tube through a yoke and a fork connection. Aileron roll feel is provided by a compression spring connected to each control wheel. The roll feel force is proportional to the displacement of the control wheel. A damping force is provided by two dampers connected to each control wheel. Movement of the control wheel moves the primary flight control cable connected to the pilot and copilot control module assemblies. The control modules are located at the aft end of the cockpit under the floor and include the following: RVDT position sensors Applied force transducers Roll trim actuator Autopilot (AP) servo motors There is only one set of roll trim switches on the trim control module on the pedestal. The trim actuator adjusts the mechanical ground of the lateral feel springs. Roll trim function is accomplished by manually activating a roll trim switch. The electrical signal from the roll trim switch commands an irreversible electromechanical actuator to move the ground point of the feel units to null the control wheel force at a given commanded position. A control column head gear set connects the control wheel to the control column inceptor through a yoke and a fork connection. (1) RVDT Position Sensors Movement of either control wheel is sensed by five RVDT sensors. The sensors are contained within a mechanical enclosure, called the RVDT cluster. The RVDT cluster is a part of the aileron section of the control module assembly. The control module contains a common shaft along the center line that simultaneously drives all five sensors. The sensors are located concentrically around the shaft. The control wheel drives the RVDT cluster through the primary flight control cables and mechanical linkage. 27-11-00 Page 2 August 15/14 GULFSTREAM G650ER SYSTEM DESCRIPTION MANUAL For each RVDT cluster, the wheel position data is supplied as follows: Two RVDTs provide data to FCC No. 1 Two RVDTs provide data to FCC No. 2 One RVDT provides data to the BFCU The FCCs and the BFCU provide the excitation signal to their designated RVDTs and receive a voltage signal back that is proportional to the control wheel positions. The RVDTs translate the sensor movement into electronic signals. The FCCs interpret the electronic signals from the RVDTs and sends commands through bidirectional ARINC 429 (A429) digital data buses in a wiring harness to the REUs located at each aileron actuator. The REUs command the hydraulic actuators that move the aileron surfaces. Two separate and independent actuators are located at each aileron surface. The outboard actuator is the EHSA and the inboard is the EBHA. (2) Applied Force Transducers The applied force on each control wheel is measured by its own force transducer. One transducer is located in the pilot control module and the other in the copilot control module. Each transducer is a two channel strain gauge, with one channel connected to FCC No. 1 and the other channel connected to FCC No. 2. The FCCs provide an excitation signal to the transducer and then receive a voltage signal back that is proportional to the applied force. Control wheel force data is used by the AP system and the FDR. The FCCs provide the data on an A429 data bus to the Honeywell Modular Avionics Units (MAUs), where the AP modules reside. The AP uses the force data to automatically disconnect and return manual control. The MAUs transmit the force data on a digital data bus to the FDR. (3) Roll Trim Actuator A single roll trim actuator is mounted in the pilot side control module and is used for normal aileron trim control. The actuator has an internal RVDT to measure its position. The data is provided to FCC No. 2 and is used to display trim indication on the Flight Control synoptic page. The roll trim actuator is an electric motor that directly moves both control wheels to accomplish the trim function. It does that by offsetting both wheels in a left or right direction to provide the flightcrew a visual feedback on the amount of trim. The offset wheel provides the same command to the FCC as if the pilot moved the control wheel manually. Electrical power to the actuator is provided through a Solid State Power Controller (SSPC) that is located within a Modular Power Tile (MPT). The SSPC performs the function of a circuit breaker. The power system Remote Interface Unit (RIU) receives a discrete ground signal from the AP disconnect switches located on each control wheel. When either switch is depressed, the RIU commands the SSPC to open the circuit, thus removing power from the actuator. This provides a quick means to disable the system in a stuck trim situation. The SSPC defaults to ON (closed circuit) if there is a loss of RIU communication. If there is an internal fault in the SSPC, it defaults to OFF (open circuit). Control power to the SSPC is provided by the MPT main feeders. The SSPC control power is lost only after all main feeders are not powered. (4) Autopilot Servo The AP supplies aircraft roll control. The AP inputs are supplied through an electric servo motor that connects to the flight control mechanical input sector. An AP servo motor is 27-11-00 Page 3 August 15/14 GULFSTREAM G650ER SYSTEM DESCRIPTION MANUAL mounted in each control module. The servos move the columns and wheels. Either pilot may override the AP system with sufficient wheel force to override the servo and disconnect the AP. The pilot side servo motor is controlled by Automatic Flight Control System (AFCS) No. 1 located in MAU No. 1. The copilot side motor is controlled by AFCS No. 2 in MAU No. 2. The servo motors are used to directly move the control wheels. There is no direct signal from the AFCS system to the FCC for aircraft control. Instead, the motors control the aircraft by moving the controls in the same manner as the flightcrew in manual control. This method has the benefit of providing the flightcrew visual feedback of what the AFCS system is doing to control the aircraft. Either motor drives the movement of both control wheels, due to the mechanical interconnect. See Aileron Autopilot System, 27-16-00, System Description for more details. B. Cockpit Flight Control Cable The cockpit flight control cables are installed between each column / wheel assembly and the associated aileron and elevator control module. The cables provide a load path between the wheel and the force feel mechanism in the control module. Each cable is 1/8 inch diameter and is made of CRES with 7 x 19 type construction. The cables are common to both the pilot and copilot aileron control installation. There are two runs of cables coming from each wheel. The cable pairs are each connected by a turnbuckle to allow correct cable rigging. To ensure against cross connecting cables, the turnbuckles have opposite threading so that only the correct cable may thread into the turnbuckles. The cockpit flight control cables extend down through each control column and through the cockpit floor. The cables connect the control wheels to a pulley assembly that connects to each control module RVDT position sensor cluster. The control wheel moves the control cables and this changes the RVDT position sensor voltage. The voltage change is provided to the two FCCs and the BFCU. C. Cockpit Flight Control Cable Retaining Pin The retaining pin is mounted in each aileron and elevator control module assembly. The pin is threaded into the underside of the chassis and is located such that it restricts the control cable from coming out of the pulley groove. D. Aileron Control Cable Pulley The control cable pulley bracket assembly is installed on the forward side of the bulkhead at FS 223. The assembly, in conjunction with the control cable pulley, transmits wheel rotational motion to linear motion. This motion is the input into the aileron section of the control module, which provides damping and force feedback to the pilot / copilot. The control cable pulley assembly redirects the primary flight control cable from a vertical position to a horizontal position prior to connecting to the RVDT position sensor cluster. E. Aileron Control Override Pushrod The aileron control override pushrod is installed ly between the pilot and copilot aileron and elevator control module assemblies. The pushrod is spring-loaded such that there are sufficient breakout forces to prevent the pushrod from extending or collapsing under normal operations. If a failure occurs causing either the pilot or copilot roll controls to jam, the person with the operational controls shall be able to provide an input force of large enough magnitude to cause the spring to breakout and allow wheel travel. 27-11-00 Page 4 August 15/14 GULFSTREAM G650ER SYSTEM DESCRIPTION MANUAL F. Aileron Aircraft (roll) control is accomplished by movement of the aileron and spoiler surfaces located on the wing. In normal operation, the FCCs transmit the commanded position on digital data buses to the REUs located at each actuator. The REUs command the electrically controlled hydraulic actuators that move the aileron surfaces. There are two separate and independent hydraulic actuators at each aileron surface. The outboard actuator is the EHSA and the inboard is the EBHA. Hydraulic power to the actuators is separate as follows: Left hydraulic system powers the left outboard and right inboard EHSA actuators Right hydraulic system powers the right outboard and left inboard EHSA actuators If both left and right hydraulic systems fail, left and right inboard aileron actuators maintain control through the EBHA. The Motor Control Electronic (MCE) in the EBHA activates a hydraulic pump that draws fluid from a self-contained compensator reservoir (manifold). The fluid allows the actuator to continue functioning as it did when fluid was provided by the aircraft hydraulic system. Aileron deflection is 11° ±1° down and 19° ±1° up. G. Aileron Trim Interconnect Pushrod The aileron trim interconnect pushrod is installed between the pilot and coilot aileron and elevator control module assemblies. The pushrod serves as a mechanical link for the copilot aileron trim. The aileron trim actuator is part of the pilot aileron and elevator control module assembly. The interconnect pushrod provides a load path from the aileron trim actuator to the copilot aileron and elevator control module assembly. The interconnect pushrod also provides a load path from the backup centering / feel ground bungee to the pilot aileron and elevator control module assembly in the event of a trim actuator disconnect failure. H. Aileron Trim Centering Bungee The aileron trim centering bungee is part of the copilot aileron and elevator control module assembly. The bungee is installed on the same crank as the trim interconnect pushrod. Under normal operation, the bungee is passive because the aileron trim actuator holds the bungee position. If the trim actuator becomes disconnected from ground, the bungee centers the control wheels and reestablishes ground. 4. Controls and Indications A. Circuit Breakers The system is protected by the following circuit breakers: NOMENCLATURE PANEL LOCATION POWER SOURCE L AIL HA LEER A9 L ESS 28VDC L AIL EBHA SEC LEER B9 L MAIN 28VDC L AIL EBHA PRI REER A3 UPS 28VDC R AIL EBHA PRI REER A4 UPS 28VDC R AIL HA REER A6 R ESS 28VDC R AIL EBHA SEC REER C7 R MAIN 28VDC 27-11-00 Page 5 August 15/14 GULFSTREAM G650ER SYSTEM DESCRIPTION MANUAL NOMENCLATURE PANEL LOCATION POWER SOURCE L AIL EBHA PWR N/A EBHA PDB (tail compartment) EBHA BUS 28VDC R AIL EBHA PWR N/A EBHA PDB (tail compartment) EBHA BUS 28VDC B. Solid State Power Controller The system is protected by the following SSPCs: NOMENCLATURE IDENTIFICATION NUMBER POWER SOURCE ROLL TRIM 2702 R ESS 28VDC C. CAS Messages The CAS messages for the system are shown in the following table: MESSAGE COLOR MESSAGE DESCRIPTION FCS Maintenance Required Blue Flight control system maintenance is required. Notify maintenance for corrective action. Roll Control Miscompare Amber Pilot and copilot control wheel positions are different. Continue flight within flight envelope limitations. Aircraft roll response with respect to control wheel input may be reduced. Pilot L-R Brake Pedal Fail Amber Pilot left and right brake pedals failed. Copilot L-R Brake Pedal Fail Amber L-R Inboard Brake Fail Amber Left and right inboard brakes failed. L-R Outboard Brake Fail Amber Left and right outboard brakes failed. Uncommanded Brake Amber Brakes are not commanded. Brake By Wire Fail Amber Brake-by-wire has failed. Retrim Left Wing Down Amber Retrim left wing down. Retrim Right Wing Down Amber Retrim right wing down. L-R Aileron Fail Amber Both REUs failed or loss of aileron command to both ailerons. Continue flight within flight envelope limitations. Attempt FLT CTRL RESET. Roll Authority Limit Amber Roll axis flight control surfaces approaching maximum displacement. Adjust flight condition as necessary. Coupling Data Invalid Amber coupling data a invalid. 27-11-00 Page 6 August 15/14 Copilot left and right brake pedals failed. GULFSTREAM G650ER SYSTEM DESCRIPTION MANUAL MESSAGE COLOR MESSAGE DESCRIPTION Speed Brake Auto Retract Amber Speed brakes (flight spoilers) automatically retracted with speed brake handle not in RETRACTED position and TLA =90% or angle of attack limiting encountered. Place speed brake handle at RETRACTED position. If unable, speed brakes will be unavailable while message is displayed. Speed Brake Fail Amber Speed brake control failed. Notify maintenance for corrective action. FCS Test Fail Amber Flight control system built-in test failed. Notify maintenance for corrective action. Ground Spoiler Red Failure of ground spoiler component or deployed ground spoiler panel. Select ground spoiler switch OFF and perform appropriate procedures. NOTE: The FCC status data required by the flightcrew is shown on the main displays as CAS messages and synoptic page data. 5. Operation A. Aileron Interface and Control Based on the pilot or copilot control wheel displacement, RVDT position sensors generate electrical commands to the FCCs. The FCCs process the RVDTs electrical commands and send augmented, shaped and scaled digital commands via a data bus to each aileron REU. Based on the FCCs commands, each REU provides electrical commands to its associated actuator, causing the aileron surface to move as commanded. (1) Aileron Control Ailerons, flight spoilers and the aileron trim tab provide aircraft roll control during normal operating conditions. The aircraft roll command is initiated when either control wheel is rotated counterclockwise or clockwise. The motion is transmitted by control cables, pulleys and control rods to the aileron and elevator control module below the cockpit floor, where signals are generated and provided to the FCCs. The FCCs send the electronics signals to the REUs located in the wing. The REUs control the actuators that move the ailerons and spoilers. The ailerons, which move in opposite directions, together with the two flight spoilers on the downward moving wing, supply the necessary aerodynamic rolling force to roll the aircraft. The flight spoilers do not move on the opposite wing. The two flight spoiler panels rise together when the corresponding aileron reaches 0.5° aileron trailing edge up. As the aileron moves back down to its neutral position, the flight spoilers also move down until they are flush with the wing upper surface. In normal operation, each aileron surface is controlled by two actuators (one EHSA, one EBHA). The two actuators are simultaneously pressurized and active (i.e., active / active configuration). The left and right inboard actuators are EBHAs and the left and right outboard actuators are EHSAs. (2) EHSA Operating Modes An EHSA is controlled electrically by its REU and uses hydraulic power to move the control surface. The EHSA system consists of the following three separate components: 27-11-00 Page 7 August 15/14 GULFSTREAM G650ER SYSTEM DESCRIPTION MANUAL REU Hydraulic manifold Hydraulic actuator The REU electronics box is mounted directly to the hydraulic manifold. The left aileron EHSA REU receives electrical power from a single circuit breaker on the left essential dc bus. The right aileron EHSA REU receives electrical power from a single circuit breaker on the right essential dc bus. The REU receives surface position commands from the FCCs on two separate and independent bidirectional A429 data buses. One bus is from FCC No. 1 and the other from FCC No. 2. The REU is mounted on its associated hydraulic manifold. It processes the FCC signals and initiates electrical commands to the Mode Select Valve (MSV) solenoid and the EHSV. The MSV and EHSV control the flow of hydraulic fluid to move the actuator in the desired direction. See Aileron Hydraulic Actuation, 27-13-00, System Description for more details. (3) EBHA Operating Modes An EBHA is controlled electrically by its REU and uses hydraulic power to move the control surface. The EBHA system consists of the following five separate components in each wing: REU MCE Two hydraulic manifolds Hydraulic actuator The REU electronics box is mounted directly to the HA hydraulic manifold. Two circuit breakers are provided for each REU to allow separate wire routing from each breaker along the leading and trailing edges of the wing. The two breakers have different power sources to provide redundancy for power bus failures. The left aileron EBHA REU receives electrical power from two separate circuit breakers. One is located on the Uninterruptible Power Supply (UPS) bus and the other on the left main dc bus. The right aileron EBHA REU also receives electrical power from two separate circuit breakers. One is located on the UPS bus and the other on the right main dc bus. If both the EBHA REU and EHSA REU are invalid, the MCE has a limited capability to control the electrical motor and actuator on its own. In that condition, the MCE receives the surface command signals directly from one of the FCCs on the MCE A429 bus. The REU receives surface position commands from the FCCs on two separate and independent bidirectional A429 data buses. One bus is from FCC No. 1 and the other from FCC No. 2. The REU processes the FCC signals and initiates electrical commands to the MSV solenoid in the HA manifold and the power select valve solenoid and EHSV in the EB manifold. Those components control the flow of hydraulic fluid to move the actuator in the desired direction. See Aileron Hydraulic Actuation, 27-13-00, System Description for more details. 27-11-00 Page 8 August 15/14