Automatic Flight Control Systems Engineering Essay

railway carmatic relief valve check g everyplacenances Engineering EssayWe live in a world where technology is, if not being improved, developed by the second. Everyday new improvements, inventions and discoveries atomic number 18 made. One industry that is always on the lead when it comes to new inventions and innovations is the air travel pains.Over the years, aircrafts gather in been facing major improvements on the structure, fuel efficiency, life-span, range of relief valve. But one of the best improvements that have been done on every aircraft (commercial) that had the biggest impact in the airmanship Industry and most probably the principal(prenominal) reason why the industry has been thriving up is the improvements done in the Avionics section, specific solelyy the Automatic outflow Controls.In the beginning, Pi the great unwasheds were trained to fly the aircrafts alone. But after some(prenominal) years, it is now the pilots computer programming the computer, telling it where to fly, at what altitude, etc. This computer is the AFCS (Automatic Flight Control agreement). In todays meansrn world of flying, it is the AFCS who is technically flying the aircraft, from cruising to arrive, and for some until parking. The AFCS has a lot of advantages when compared to human pilots when it comes to flying. Here are some of themThe AFCS has the ability to overcome deficiencies when it comes to perceptual constancy and control.The AFCS improved the handling qualities. Such as, when the airspeed or the altitude of the aircraft needs to be constant.The AFCS is more accu identify and hence is able to carry out several tasks that the pilot is not able to do.* commencement Emi scores zephyr Colleges Automatic Flight Control Systems Book (Chapter 3.1.3)To get a better understanding of the AFCS, the dispa point parts of it will be discussed, such as the Autopilot System, Flight conductor System, Auto Throttle System and etc.The information most the AFCS will be based on one of Boeings classic aircrafts, the 737-500. race MANAGEMENT SYSTEM (FMS)The Flight Management System is glide, combined leak control, a Built-In Test Equipment (BITE) and a guidance system. The FMS provides control and surgical operation of fivesome autarkic subsystems to provide lateral navigation (LNAV) and vertical navigation (VNAV) for performance management and optimum flight profiles. The Flight Management System is not labeled to all control panel or any single component as it is an integration of five independent subsystems. These subsystems areDigital Flight Control System (DFCS)Inertial Reference System (IRS)AutothrottleElectronic Flight Instrument System (EFIS)Flight Management ready reckoner System (FMCS)* Source building blocked Airlines Boeing 737-322/522 (page 6, Chapter 22-2, Oct 99) from Emirates Aviation College LibraryThis system was kno buffer to increase fuel efficiency, safety and decrease workload. For both(prenominal) pilots , this means that they nooky select full FMS operation or Autopilot Flight Director System (AFDS) for a complete automatic flight. They whoremonger even practice session the Control Display Units (CDU) to provide, for manual flight, reference information. Management and operation is wholly under the control of the flight crew. There are only real operations that can only be implemented by the flight crew. They are landing rollout steering, thrust reversal, speed pasture brake operation, altitude selection, landing gear and flap operation, instrument landing system (ILS) tuning, thrust initiation, brake release, airplane rotation and steering during takeoff roll.* Source joined Airlines Boeing 737-322/522 (page 6, Chapter 22-2, Oct 99) from Emirates Aviation College LibraryFMS BUILT-IN TEST EQUIPMENT (BITE)Ground mental test capabilities and self-contained in-flight monitor are provided for the FMS subsystems. The flight management computer (FMC) coordinates the BITE testing o f the five subsystems and must be functional for access to any subsystems built-in test equipment. BITE for the FMS subsystems is accessed from both CDUs locate in the cockpit. Each FMS subsystems run its sustain systems test. Included in the tests are for its computers, sensor inputs and several interfaces. Any switch findings during flight are automatically stored for analysis on the ground which is accessed by the bite system.* Source United Airlines Boeing 737-322/522 (page 8, Chapter 22-4, Oct 99) from Emirates Aviation College LibraryTHE BOEING 737-500 CATEGORY*3General AFCS Category cleverness Chart*4Boeing 737-500 AFCS Category Capability ChartThe Boeing 737-500, according to the diagram is in Category 3B. In vow for this aircraft to operate at Cat3B weather minimums, the equipment that must be available in Cat2 should be functional. These equipment are some(prenominal) Flight DirectorsOne Autopilot in CMDboth Air Data Systems (ADS) twain windshield wipersTwo generator s both(prenominal) EFIS systems displayingRadio AltitudeGlideslope and Localizer DeviationAttitudeAutopilot Status engaged Pitch and Roll ModesDecision HeightBoth Radio Altimeter SystemsBoth ILSMarker BeaconBoth IRSNow for the aircraft to operate in Cat3B all the equipment listed for Cat2 must be fully operational, provided that the equipment as follows is includedThe AutothrottleBoth AutopilotsBoth Hydraulic Systems* Source United Airlines Boeing 737-322/522 (page 12, Chapter 22-8, Oct 99) from Emirates Aviation College LibraryAUTOMATIC line of achievement CONTROL SYSTEM (AFCS)The AFCS or also known as Auto Flight System (AFS) comprises of three independent systems. They areA gape dampish SystemA dual Digital Flight Control System (DFCS)An Autothrottle (AT) SystemThese 3 systems provide automatic aircraft stabilization close the roll, pitch and goggle axis. The AT and the DFCS systems control the aircraft with the selected Mode Control grace (MCP) guidance from N1, heading, radio, IRS, FMC and ADC inputs.* Source United Airlines Boeing 737-322/522 (page 10, Chapter 22-6, Oct 99) from Emirates Aviation College Library gawp-DAMPER SYSTEMThe goggle wet System is composed of various components, such as be Damper Engage switchWarning Annunciator gawk Damper sexual unionIntegrated Flight System Accessory Unit (IFSAU)swerve Damper Engage solenoidPosition Transducer and Transfer Valve on the rudder Power Control Unit (PCU) gape Damper position Indicator* Source United Airlines Boeing 737-322/522 (page 12, Chapter 22-8, Oct 99) from Emirates Aviation College LibraryThe gawk Damper System smoothens the flow of air that causes the aircraft to swerving and thus causes it to Dutch Roll. The Dutch Roll is a phenomenon that occurs when a sidewind hits the aircraft which causes it to yaw. This yawing trend exposes one side of the wing to the wind more than the other side. The undefendable side of the wing, gains more speed and more speed generates more nose on that particular side. The lift that was generated on the exposed side of the wing causes the aircraft to roll. Hence, the term Dutch Roll.The swerve Damper System is a stability augmentation system that works full time, providing yaw axis damping for the complete flight, including both takeoff and landing. It is connected in series so that none of the rudder feedback is use to the pedals. This now allows the Yaw Damper System to operate in an independent manner without interfering the initiated rudder commands by the flight crew. Both the yaw rate and the yaw direction are detected using a rate sensor located in a Yaw Damper Coupler. The rate sensor of the Yaw Damper is sensitive that the rudder is displaced at a good time to dampen out any sidewinds hitting the aircraft before it can obviously affect the flight path of the aircraft.* Source United Airlines Boeing 737-322/522 (page 12, Chapter 22-8, Oct 99) from Emirates Aviation College LibraryThe Yaw Damper authority is only 3 deflexion of the rudder. Its actuator gets no turning commands from the longitudinal axis AP. The Boeing 737-500 does not have a 3-axis AP. It only has 2 which is the pitch and roll axes only. In this aircraft, turn coordination is not available. A roll command which sends a cross feed augur in proportion to the bank angle due to aircraft banking, is sent to the Yaw Damper to prevent undesirable opposition to roll attitude.* Source United Airlines Boeing 737-322/522 (page 12, Chapter 22-8, Oct 99) from Emirates Aviation College Library*5Yaw Damper System plotYaw Damper OperationThe Yaw Damper is confined to 3 modes of operation. These modes are synchronization mode, engaged mode interlocks and logical system and engaged mode operation. Before the yaw axis engagement, the Yaw Damper pairing is in the synchronization mode for 2 seconds. The synchronization mode provides a unprofitable turnout to the electro-hydraulic transfer valve to prevent a sudden change in the Yaw Damper co upler. The mode is accomplished by returning the controlled prefigure back to the output amplifier. The output of the valve amplifier is reduced to null as the output of the integrator increases, causing the signal to be cancelled. Prior to the engagement of the Yaw Damper its actuator remains at the center which nulls the position feedback to the Yaw Dampers coupler.* Source United Airlines Boeing 737-322/522 (page 14, Chapter 22-10, Oct 99) from Emirates Aviation College LibraryThe system is activated by placing the Yaw Damper switch on the flight control module to ON. Both Bs of the flight control switch and system hydraulic proponent must be ON and available, respectively, in order to power the Yaw Damper actuator portion of the PCU. 2 seconds after the Yaw Damper is on, the YAW DAMPER light extinguishes. The Integrated Flight Systems Accessory Unit (IFSAU) contains the logic to engage the system, monitor the engagement and illuminate the amber-colored Yaw Damper disengaged an nunciator light. If, for over 2 seconds, the AC power is lost, the YAW DAMPER light illuminates and the Yaw Damper switch returns to OFF position. The Yaw rate gyroscope which is located inside the Yaw Damper coupler senses the movements by the yaw axis. The coupler only responds to yaw movements that produce the Dutch Roll. Before the command signals are applied to the transfer valve which is located inside the Yaw Damper actuator, it is head start filtered and amplified. The transfer valve then sends hydraulic pressure in order to sidestep the rudder and reduce the aircrafts oscillation by the yaw axis. The output of the Yaw Damper actuator is summed with the rudder pedal manual input in order to move the main rudder Power Control Unit (PCU) that controls the rudder. Now as the actuator moves the linear inconstant displacement tranducer (LVDT) supplies the signal of the position feedback to nullify the signal coming from the yaw rate gyroscope. When the movement (by the yaw axi s) stops, the feedback signal returns the rudder to the original position.