ATI T-18 yaga

Resolver

A rotary electromechanical device that performs trigonometric computations electrically

Resolvers

Can seperate a vector quantity into two right angle componenets, sine and cosine for resolution. Can combine vectors to produce the sum of the 2 original vectors.

Resolver

An analog electromagnetic transducer that can be used in a wide variety of position and velocity feedback applications, due to its simple transformer design and lack of any on board electronics

Resolver

Also considered a rotary electrical transformer used for measuring degrees of rotation

Brushless transmitter

The most common type of resolver

Stator

The part of a resolver that delivers the absolute angle position

50-60 & 400

Resolvers designed for terrestrial use tend to be driven at ____-____ Hz (utility frequency) while those for marine or aviation use tend to operate at _____ Hz.

A resolver consists of

A cylindrical rotor with each of the two phases of rotor and stator in space quadrature

90 degrees

The resolver rotor constructed of two windings electrically isolated from each other and displaced by _____.

Resolution

Resolvers can separate a vector quantity into its two right angle components, the sine and cosine.

Resolution (polar-to-rectangular conversion)

Input signals are applied to the stator winding and the outputs are taken from the rotor windings

Composition (rectangular-to-polar conversion)

Resolvers can combine two right angle components to produce a vector

Voltage gradient

In resolver electrical parameters the term sensitivity is also called:

Phase shift

Another resolver electrical parameter is determined in the rotor first angular position in EZ corresponding to the maximum coupling and it's called __________ ___________

CRT (Cathode Ray Tube)

Converts electronic signals to visual displays such as pictures, RADAR sweeps, and waveforms.

Electron Gun, Deflection system, and screen

All CRTs contain three main elements:

Thermionic emission

Electrons are boiled off the cathode by:

The purpose of the deflection system

To bend or deflect the electron beam inside the cathode day tube (CRT) to illuminate or "paint" lines, symbols, and any other desired image on the CRT screen.

Attract

A positively charged electrostatic deflection plate will _________ the electron beam

Electrostatic deflection

Uses plates that develop electrostatic fields similar to those developed by the plates of a capacitor to deflect the beam. Primarily used in test equipment, such as oscilloscopes.

Repel

A negatively charged electrostatic deflection plate will _______ the electron beam.

Glow

A CRT screen will ______ when struck by the electron beam.

Preferred system for RADAR indicators features are:

Increased control of the beam, improved deflection sensitivity, better beam position accuracy and simpler construction

Directivity

Refers to the degree of sharpness of an antenna beam

Directional antennas

Radiate RF energy in lobes or beams that extend outwards from the antenna in one direction or only a few directions for a given antenna position

High directivity

With directional antennas, If the beam is narrow in either the horizontal or vertical plane, the antenna is known to have ______ __________ in that plane.

Power gain

The ratio of the radiated power to that of the reference antenna, which is usually a basic dipole.

A paraboloid

Shaped reflector can focus microwave energy into a sharp, narrow beam.

Cosecant-Squared Reflector

A modified version of the parabolic reflector designed to produce a non-uniform distribution of a radiated energy.

Cosecant- Squared Beam

Should not only be narrow in the horizontal plane and broad in the vertical plane but also distribute a greater proportion of power to more distant targets.

IFF (Identification Friend or Foe)

An electronic system that uses a coded RADAR transmission to distinguish friendly forces from enemy forces

Primary purpose of IFF

To provide automatic identification of friendly aircraft, ships, or ground forces by transmitting a coded reply when triggered by a coded challenge from associated IFF units

IFF equipment

Used to identify a particular target in a group of friendly targets

Model 1 and 2 of the IFF system

Used by military aircraft

Airborne IFF systems

Have provision for 5 different modes of operation

Transponder

Component in the aircraft that receives the challenge and sends a coded reply

Transponder control box

Determines the reply code

Coded reply

Displayed on the search radar scope after it has been decoded by associated equipment in the system.

Interrogator

The component that initiates operation of the system. It sends the challenge (interrogation) to the aircraft and receives the coded reply (response).

The interrogator in a ground station

Transmits the challenge in two different types of antennas: omnidirectional and unidirectional

Coded reply

Only the ________ ________ received by the unidirectional antenna, which is slaved to the RADAR search antenna, is utilized or displayed

The interrogator in an airborne station

Uses only one unidirectional antenna

The transponder receives the challenge and transmits a coded reply on a omnidirectional antenna

Previous position, course, speed, elapsed time

Dead reckoning is the process of estimating ones position from the following known information:

INS (Inertial Navigation System)

Completely self-contained and does not require any information from outside the aircraft. This makes it impervious you enemy countermeasures

INS

Can measure ground speed in the presence of wind and is completely independent of operations environments

Integration

The process of summing all rate-of-change values that occur within limits of the time of the time period being considered

F=MA

Formula that expresses Newton's Second Law

F=Force M=Mass A=Acceleration

Newton's Second Law

Acceleration is proportional to the resultant force and is the same direction of this force

East-West axis

Direction of motion for the X Accelerometer

North- South

Direction of motion for the Y Accelerometer

vertical acceleration

Direction of motion for the Z Accelerometer

Accelerometers

Are arranged on the plate form to supply specific components of acceleration

Gravity

In an aircraft that changed attitude while maintaining constant speed, accelerometers on an unstabilized platform would sense acceleration due to ________

For INS to provide accurate positional data

The platform on which the accelerators are mounted must be maintained horizontal to the Earths surface and aligned to true North.

Gyrostabilized platform

Will tend to maintain an aircrafts orientation in space as it flies over the surface of the earth, beginning at the North Pole

Gyro-Torquing

A continuous torque is applied to the appropriate gyro axis to reorient the gyro and maintain the platform horizontal to the earth and aligned to true north

Schuler tuning

Used to maintain the stable element horizontal to the horizon and prevent large velocity and distance errors, which would result from misalignment of the platform.

Schuler tuned loop

Closed loop circuit between accelerometer, velocity integrator, and stable element

Accelerometers, integrators, stable platform, and computer

INS is composed of four basic components

Computer

Receives the signals from the integrators and changes the distance traveled into a position in the selected coordinates.

Centripetal Errors

False accelerations sensed when the platform is torqued to maintain its plane of reference above or below the equator

Coriolis Effect

As an aircraft travels over the surface of the earth, the earth itself rotates, exhibiting a constant East velocity, which is maximum at the equator and progressively less at higher latitudes

TACAN

Provides azimuth to known station, Identification (ID) of the station with Morse Code, and slant-range distance to the station

126

TACAN uses ____ two-way channels in the frequency range of (962 to 1213) MHz

63

The receive frequency for a TACAN is exactly _____ MHz above or below the transmit frequency.

Surface transmitter

Continuously transmits azimuth information and transmits range information when interrogated

In TACAN receive mode

The aircraft receives bearing and station ID only. The aircraft TACAN transmitter is disabled to ensure radio silence

In TACAN transmit/receive mode

The aircraft receives bearing, station ID, and slant range to the selected station

In TACAN Air-to-Air mode

Measures range to another aircraft

When using air-to air mode

The TACAN sets in the aircraft must be set 63 channels apart to simulate the spacing between transmit and receive frequencies.

Marconi antenna

This antenna is electrically a one-half wavelength vertical antenna. Used by a TACAN surface station

One quarter

A Marconi antenna is physically ______ ___________ wavelength long

Basic function of the aircraft TACAN subsystem

To provide navigation information to the pilot and aircrew

2 (top and bottom)

Most navy aircraft have ___ TACAN antennas, _________ of the fuselage