GA-3
gyro unit
Description
GA-3 directional gyro unit for aircraft heading systems
GA-3 is an aircraft gyro unit used as a sensitive heading reference element in precision aircraft heading systems. The unit is a three-degree directional gyroscope intended to measure, store and transmit aircraft heading data to onboard consumers. Depending on the installed system, GA-3 can provide orthodromic, magnetic or true heading information to autopilot systems, navigation computers and cockpit indicators.
Full descriptionCollapse description
Function of the GA-3 gyro unit
The main function of GA-3 is stable heading storage and heading signal output during flight. The gyro axis maintains its spatial direction, while aircraft turns are detected by angular sensing elements and converted into electrical heading signals. These signals are used by the aircraft heading system and related navigation equipment. GA-3 is especially important in operating modes where magnetic references are less reliable, including maneuvering flight, turbulence and operation in high-latitude areas.
GA-3 in TKS and GMK heading systems
GA-3 is used in aircraft heading complexes such as TKS-P, TKS-P2, GMK-1G and GMK-1AE, depending on aircraft type and avionics configuration. In these systems, the unit operates together with heading correction equipment, magnetic sensors, control panels and signal distribution circuits. For increased reliability, aircraft heading systems may include two or three GA-3 gyro units, typically arranged as main, control and reserve channels.
Operating modes of the GA-3 gyro aggregate
In DG mode, the GA-3 works as an autonomous directional gyro and stores the selected heading reference. This mode is used for accurate heading holding and stable navigation output. In magnetic correction mode, the gyro unit can be synchronized with a magnetic heading source, such as an induction magnetic sensor, for initial heading alignment or correction during stable straight flight. Latitude correction may also be used to compensate for Earth rotation according to the current flight latitude.
Construction features of GA-3
The GA-3 unit contains a high-speed aircraft gyro motor in a sealed metal housing. The source context indicates the IAV-824 gyro motor or an equivalent type. The rotor operates at high speed, creating the kinetic moment needed for stable directional reference. The unit includes a heating assembly with thermal elements and a bimetallic relay to maintain reliable operation at low temperatures. It may also include a gyro topple warning function when aircraft maneuvers exceed the operating limits of the gimbal suspension.
Installation and maintenance of GA-3
GA-3 is mounted on a special frame with shock absorbers to protect the gyro mechanism from vibration and impact loads. During installation, the base plane must be aligned with the aircraft construction axis according to maintenance documentation. The sealed metal casing may include an inspection window for visual monitoring of the internal gimbal frame. Before procurement or replacement, the required aircraft system, modification, condition, passport availability and test status should be confirmed.
Technical details
- Product Type
- Aircraft directional gyro unit / heading reference gyro aggregate
- Designation
- GA-3
- Alternative Designations
- GA 3, GA-3 gyro unit, ГА-3, гироагрегат ГА-3
- Function
- Measurement, storage and output of aircraft heading data
- Heading Data Types
- Orthodromic, magnetic or true heading depending on system configuration
All specificationsCollapse specifications
- Gyro Type
- Three-degree directional gyroscope
- Parent Systems
- TKS-P, TKS-P2, GMK-1G, GMK-1AE according to source context
- Application / Where Used
- Aircraft heading and navigation systems
- Compatible Aircraft / Equipment
- Tu-154, Il-76, Yak-42 and other aircraft depending on installed heading system documentation
- Typical System Redundancy
- Two or three GA-3 units in main, control and reserve channels, according to source context
- Operating Modes
- DG mode and magnetic correction mode
- Correction Functions
- Latitude correction and magnetic correction depending on system configuration
- Associated Magnetic Sensor
- ID-3 induction magnetic sensor, according to source context
- Gyro Motor Type
- IAV-824 three-phase asynchronous gyro motor or equivalent, according to source context
- Rotor Speed
- 22,000–22,500 rpm
- Gyro Kinetic Moment
- Approximately 1.96 N·m·s
- AC Power Supply
- Three-phase 36 V, 400 Hz
- Electrical Connector
- Specialized 30-pin plug connector, according to source context
- Azimuth Drift in DG Mode
- Not more than ±1° per 30 minutes
- Normal Azimuth Correction Rate
- Not less than 40 angular minutes per minute
- Fast Azimuth Correction Rate
- Not less than 2° per second
- Maximum Dimensions
- 390 × 272 × 252 mm, including shock-mounted frame
- Weight
- Not more than 13.2 kg
- Vibration Resistance
- Up to 0.5 mm amplitude at 15–20 Hz, according to source context
- Shock Load Resistance
- Up to 4g short-term shock loads, according to source context
- High-Frequency Vibration Reference
- Up to 2.3g at 80 Hz, according to source context
- Heating
- Internal thermal elements and bimetallic relay
- Mounting
- Special mounting frame with spring or rubber shock absorbers
- Installation Alignment
- Base plane aligned with aircraft construction axis within ±1°, according to source context
- Inspection Feature
- Inspection window on sealed metal casing, according to source context
- Technical Documentation
- Product passport, test report, storage records and aircraft heading system documentation if available
Payment & delivery
Orders ship from our hub in Dubai. Partner stock is first transferred to Dubai, then shipped to you.
Dubai stock: 100% before dispatch. Partner stock (Remote stock) and Pre-order: 50% advance payment to start the order and 50% before shipment from Dubai to you.
Availability, lead time, delivery cost and payment terms are confirmed for your order before payment.
Payment & delivery terms






