GA-1PM Series 2

GA-1PM Series 2 gyroscopic unit for heading systems

GA-1PM Series 2 is an aircraft gyroscopic unit used as a central sensitive element in heading systems and navigation complexes. The unit is based on a three-degree gyroscope with a horizontal spin axis and is used to determine, stabilize and maintain the gyroscopic heading of an aircraft or helicopter. It provides remote electrical heading data to cockpit indicators, navigation equipment and other onboard consumers.

Function of the GA-1PM Series 2 gyro unit

The main function of GA-1PM Series 2 is to form and preserve the aircraft heading reference. The unit determines the heading angle, averages heading information and maintains the selected gyroscopic course during operation. It can transmit angular heading deviations to indicators such as UGR-4UK and to other aircraft systems. In the heading system, GA-1PM Series 2 works as an internal electromechanical reference unit, not as a standalone cockpit display.

GA-1PM Series 2 in GMK and KS heading systems

GA-1PM Series 2 is used in aircraft heading systems and related navigation complexes. The source context mentions KS-3G, GMK-1A and GMK-1AE type systems. In these systems, the gyro unit supplies heading data and supports operation in gyroscopic heading mode or with external correction. Depending on aircraft configuration, correction may be provided from magnetic or astronomical reference sources. Actual compatibility must be confirmed through the aircraft equipment list and heading-system documentation.

Operating modes of GA-1PM Series 2

The GA-1PM Series 2 unit can operate in gyroscopic semi-compass mode and in corrected heading modes. In gyroscopic semi-compass mode, the unit preserves heading using the internal gyroscope. In corrected modes, external heading references can be used to reduce drift and maintain more stable course information. The unit includes follow-up, correction and signal-transmission circuits that allow heading information to be distributed to aircraft consumers.

Installation of GA-1PM on Mi-8 / Mi-17 aircraft

The source context indicates wide use of GA-1PM Series 2 on Mi-8 / Mi-17 family helicopters, including Mi-8T, Mi-8MT, Mi-8MTV and related versions. The unit is installed in a technical area rather than in the pilot cockpit. On Mi-8 helicopters, the gyro unit may be installed in the radio compartment or other specialized technical bay on a shock-mounted frame. This placement reduces the influence of vibration, fuselage deformation and magnetic interference from cockpit instruments and metal masses.

Ordering and replacement of GA-1PM Series 2

When ordering GA-1PM Series 2, the buyer should specify the exact designation, series, aircraft type and installed heading system. It is also important to confirm whether the unit is required alone or with a mounting frame. Product passport, repair certificate, test report, storage records and compatibility with GMK / KS heading-system equipment should be checked before supply. Interchangeability must be verified through aircraft maintenance documentation and wiring diagrams.

Product Type: Gyroscopic unit / directional gyro assembly
Designation: GA-1PM Series 2
Alternative Designations: GA-1PM ser.2, GA-1PM Series 2, ГА-1ПМ серия 2, ГА-1ПМ сер.2
Function: Determination, stabilization and preservation of aircraft gyroscopic heading
System Role: Central sensitive element of aircraft heading systems
Application / Where Used: Heading systems, navigation complexes, cockpit indicators and onboard heading-data consumers
Associated Systems: KS-3G, GMK-1A, GMK-1AE according to source context
Compatible Aircraft / Equipment: Mi-8 / Mi-17 family helicopters and other aircraft depending on documentation
Related Aircraft Versions: Mi-8T, Mi-8MT, Mi-8MTV, Mi-17 and related modifications according to source context
Gyroscope Type: Three-degree gyroscope with horizontal spin axis
Operating Modes: Gyroscopic semi-compass mode and corrected heading modes
Correction Sources: Magnetic or astronomical external correction depending on system configuration
Output Consumers: UGR-4UK indicator and other onboard systems according to source context
Azimuth Drift in GPK Mode: Not more than ±2.5° per hour on a stationary base, according to source context
Remote Transmission Error: Not more than ±0.6°, according to source context
Azimuth Correction / Erection Rate: 2° to 4° per minute, according to source context
Readiness Time: Not more than 5 minutes after power-up
AC Power Supply: Three-phase 36 V AC, 400 Hz
DC Power Supply: 27 V DC
DC Circuits: Control circuits, potentiometers and correction circuits, according to source context
Housing Form: Cylindrical metal body with inspection glass and connector at the base
Approximate Housing Diameter: About 175–180 mm
Approximate Height: About 220–235 mm including connector
Approximate Weight: About 4.5–4.7 kg
Approximate Installed Set Weight: Up to about 5.2 kg with transition mounting frame, according to source context
Mounting: Shock-mounted frame in radio compartment or technical bay
Installation Restriction: Not normally installed in pilot cockpit due to magnetic interference, size and service requirements
Condition: New / As-Stored / Overhauled / Serviceable, depending on availability
Technical Documentation: Product passport, repair certificate, test report, storage records and heading-system documentation if available

All shipments are carried out from our international warehouse in Dubai (UAE), as well as from our partners’ remote warehouses.

In Stock — items available in stock at the Dubai warehouse are dispatched within 5–10 business days after receiving 100% prepayment.

Remote Stock — items available at our partners’ remote warehouses are supplied within an average of 30–45 business days after receiving 100% prepayment.

Pre-Order — made-to-order products are manufactured and delivered within an average of 45–60 business days. Payment terms: 50% advance payment to start production, with the remaining 50% paid before dispatch from the Dubai warehouse after full readiness for shipment.

Returns & Changes (Restocking Fee)
For selected items, a RESTOCKING FEE of 10% may apply in case of return, order cancellation, or changes to the order specifications. This condition applies only to certain products and is confirmed at the order approval stage.

Warranty
All products are covered by a standard 6-month warranty.
Extended warranty is available upon request and is agreed individually; it may affect the final product price.