Category: Flight Instruments

Inertial Reference System Introduction to Inertial Reference System Inertial reference system is a stand alone system providing accurate position Ring laser gyro and computers with high computing power are used in IRS Acceleration in pitch, roll and yaw axis is measured and integrated To compare, INS measures accelerations in East West and North South Inertial reference system is a strap down system Gyroscopes and accelerometers are fixed to airframe Reduction in moving parts increase accuracy and maintainability Sagnac Effect Ring laser gyro uses Sagnac effect of laser source to measure…

Inertial Navigation System Introduction to Inertial Navigation Systems INS is an accurate navigational aid for pilots The instrument is independent of any ground installation INS is capable of world-wide operations Advanced form of deduced reckoning is used in INS Inertial Navigation System comprises of three parts inertial navigation unit Mode selector unit Control and display unit Principle of Inertial Navigation Systems Accelerometers and Integrators are the core of Inertial Navigation Systems High grade accelerometers provide acceleration or deceleration Acceleration Integrators integrates acceleration to obtain velocity Velocity integrators further integrates velocity…

Aircraft Magnetism Introduction to Aircraft Magnetism Compass north is the north indicated by an aircraft’s compass needle Compass north deviates from magnetic north due to deviation Aircraft magnetism induces deviation error in the compass Ferrous metals and electrical fields cause aircraft magnetism Deviation is the angular difference between compass and magnetic north Compass swing procedure enables us to correct deviation in our compass Deviation Compass Swing Compass swing is used to calculate, correct and record residual error Aircraft’s compass is compared with datum compass outside the aircraft Deviation on cardinal…

Gyro Magnetic Compass Introduction to Gyro Magnetic Compass Remote indicating compass reduces limitations of direct reading compass In accurate headings during acceleration and turns High deviation due to magnetic sensing element situated in the cockpit Magnetic headings cannot be provided to other instrument Gyro magnetic compass has a directional gyro monitored by compass Drift of gyroscope is corrected by magnetic detector Gyro has a slow precession rate of 3 degrees per minute Slow precession rate damps flux valve errors of magnetic detector Construction of Gyro Magnetic Compass Gyro Magnetic compass…

Turn and Slip Indicator Introduction to Turn and Slip Indicator Turn and slip indicator consists of a turn indicator and a slip indicator Turn indicator has a horizontal rate gyro which measures rate of turn Horizontal rate gyroscope measures rate of turn around the vertical axis Turn indicator has lower rotor speed to use the property of precession Low RPM reduces rigidity and increase precession Slip indicator is a pendulous device indicating balance during turn Turn co-coordinator is an advanced form of turn and slip indicator Rate of Turn Indicator…

Artificial Horizon Display of an Artificial Horizon Artificial horizon provides attitude of aircraft using a vertical axis gyro The gyro spin axis is maintained vertical to earth surface by gravity Gull wing etched on the outer glass moves with aircraft in pitch and roll The horizon image attached to an earth gyro maintains its orientation Nose up indication shows gull wing above the horizon Gull wing attached to outer gimbal moves down by a guide pin system Horizon bar attached to the inner gimbal retains its vertical position Artificial horizon…