Flight Detector Indicator

Transcription

1 Flight Detector Indicator Part No: Components Maintenance Manual No: By Soumyadeep Das Raj shekhar Chatterjee

2 Purpose of equipment: The flight detector indicator (FDI) is a part of the integrated flight system. It is used as a primary attitude indicator, presents a symbolic picture of aircraft pitch and bank attitude. It provides command information for intercepting and following the localizer and glides slope beams or for intercepting and following a selected course and attitude. Equipment specification: Physical Specifications Size Bezel size 5.00in wide by 5.25in high Case size 4.875in wide by 5.125in high by 7.50in long Weight Environmental specifications Ambient temperature Humidity Altitude Magnetic effect Electrical Specifications Flag meter 2.0mA Pointer meter 5.0mA 3.4Kg max Operation: -30C⁰ to +55⁰C Storage :-65⁰ to +75⁰C Test: Normal factory ambient Relative Humidity: 95% at +2⁰ to +32⁰C Absolute Humidity: 95% of relative humidity at +32⁰C from +32⁰ to +72⁰C to +5000ft 5⁰ max deflection 1-1/2in bar magnet at 12in.

3 Equipment Description: Electromechanical description: The FDI presents a pictorial display to the pilot of the aircraft attitude and flight director information by means of a symbolic three dimensional forward view display. The basic attitude display consists of a flat artificial horizon tape that is servo driven in both pitch and bank and is read against the fixed aircraft symbol in the centre of the instrument. A bank angle scale at the top of the display and pitch reference marks on the horizon tape are used for precise attitude manoeuvres. Steering commands are displayed by the command bars that consist of two tapered bars forming an inverted V, flanking the aircraft symbol. The command bars move in unison and are servo driven in both pitch and roll to command the required changes in attitude. Theory of operation: General operation: The FDI displays attitude, attitude commands, runaway position, glide slope positions, speed commands and rate of turn. Two servos, each are used to position an attitude display, a command display and a run way display. The meter movements position a glide slope, a speed command and the rate-of-turn display. An additional six-meter movements holds warning flags out of view if monitor signals representing proper system operations are present. Attitude displays: General Operations: A vertical reference provides signals representing the actual pitch and bank attitude of the aircrafts. Pitch display functional operation: The horizon is represented by a heavy line on the attitude tape behind the fixed aircraft signals and the command bars. The attitude tape displays the pitch attitude of the aircraft and is calibrated for pitch angles both up and down. Roll (bank) display functional operation: Bank angle is displayed by a pointer that is read against a fixed bank scale at the top of the FDI and by the rotation of the attitude tape with respect to the aircraft symbol. Attitude servo monitors: Logic circuits in an associated instrument amplifier check for several conditions necessary for proper system operation. If all these conditions are satisfied, the instrument amplifier provides a +28V DC monitor symbol to the FDI and a meter then moves the GYRO flag out of view. Failure mode logic switching: In dual system operation, separate vertical references supply attitude information to the pilot s and co-pilot s FDIs. Some system include a switching function, so if one vertical reference fails the FDI supplied by the failed vertical reference can be provided with reliable attitude information derived from the other vertical reference.

4 Alternatively a manual switch may provide the same switching function if a GYRO flag appears in wither indicator, the [pilot can switch over the attitude inputs of that FDI to the bootstrap synchros of the other indicators. Comparator warning monitor: Differential resolvers in the pilot s and co-pilot s FDIs can be used to verify that both indicators display the same attitude. Command display: General operation: Associated steering computers combine inputs from compass system, vertical reference, various navigation receivers, and/or data sensors. These computers provide pitch and bank signal representing the commands needed to make good a desired path of flight. The FDI uses these signals to position a command display. Pitch command functional operation: Pitch command motor-generator positions the command bars and the rotor of pitch command transmitter. The output from the transmitter is applied to the instrument amplifier as a command bars pitch position signal. The instrument amplifier combines the position signal with a pitch command signal from the pitch steering computer. Bank command functional operation: Bank command motor generator positions the command bars and the rotor of bank command transmitter. The output from the transmitter is applied to the instrument amplifier as a command bars roll position signal. The instrument amplifier combines the position signal with a bank command signal from the bank steering computer. Command servo meters: If all conditions necessary for proper system operation are satisfied, the instrument amplifier provides the +28V DC monitor system to the FDI and a meter positions the CMPTR flag out of view. Run way display: General Operations: An associated navigation receiver provides a localizer signal that represents the horizontal direction to the runaway. A radio altimeter provides a signal representing distance above ground. The FDI uses these signals to position a runway display to shot the position of the runaway in relation to the aircraft. Runway altitude functional operation: Motor generator positions the rotor of the runway altitude transmitter and drives the runway symbol vertically. The instrument amplifier combines the positional signal with the input from the radio altimeter. If a difference exists, a servo drive signal is applied. Runway localizer functional operation: Motor generator positions the rotor of the runway localizer transmitter and drives the runway symbol left and right. The instrument amplifier combines the positional signal with the localizer signal from the navigation receiver. If a difference exists, a servo drive signal is applied. Runway servo monitors: If all conditions necessary for proper system operation are satisfied, the instrument amplifier provides a +28V dc monitor signal to the FDI and a meter positions the RUNWAY flag out of view.

5 Glide slope display: The navigation receiver provides a glide slope drive signal representing deviations from the glide slope beam. An indicator has a zero centre meter movement that positions a pointer to show the directions to the glide slope beam in relations to the foxed airplane symbol. Failure of the navigation receiver causes a +28V DC glide slope flag signal to disappear. Speed command display: The speed control or automatic throttle system provides a speed command signal to the FDI. An indicator has a zero centre meter movement that positions a pointer to show deviations from either the pitch attitude, necessary to maintain a desired air speed, or deviations from the throttle setting, necessary to maintain a desired path of flight. System failure causes a +28V DC speed flag signal to disappear. Rate-of-turn Display: The rate-of-turn sensor provides a rate of turn signal to the FDI. An indicator has a zero centre meter movement that positions a pointer to show deviations to either the left or right of a forward flight path. System failure causes a +28V DC R/T flag signal to disappear.