A-037-1

A-037-1 transceiver in the A-037 radio altimeter set

The A-037-1 is the main transmitting and receiving unit of the A-037 radio altimeter set. It measures true aircraft height above land, water or rough terrain and supplies altitude information to cockpit indicators and related onboard systems. The unit is used on fixed-wing aircraft and helicopters, including Mi-8, Mi-17 and Mi-171 series helicopters, depending on the installed avionics configuration. The A-037-1 is not a cockpit indicator. It is the electronic measuring block that forms the core of the radio altimeter system.

Operating principle of the A-037-1

The A-037-1 works as a continuous-wave radar with frequency modulation. The transceiver sends a radio-frequency signal toward the surface below the aircraft, receives the reflected return signal and processes the difference between transmitted and received signals. This allows the system to determine true altitude in real time. The measured value is then sent to the pointer indicator, warning circuits and system outputs. This type of measurement is especially important at low altitude, where barometric altitude does not show the actual clearance below the aircraft.

Altitude indication and warning functions

In the A-037 radio altimeter set, the A-037-1 provides data for continuous cockpit indication of current true altitude. The system can also generate low-altitude warnings when the aircraft descends below a preset threshold. Warning output may include both visual and aural indication, depending on the aircraft configuration and connected equipment. If the system detects a fault, loses radar contact with the surface, or the aircraft flies outside the operating altitude range, a fault flag appears on the indicator scale. This helps the crew understand when the displayed altitude should not be trusted.

Electronic structure of the A-037-1 unit

The A-037-1 includes receiving, transmitting, signal-processing and monitoring circuits. The unit forms the electronic core of the A-037 system and works together with the cockpit pointer indicator, antennas, wiring and warning devices. The housing is metallic and has a perforated U-shaped top cover. Manual access points for “1RS” and “2RS” adjustments are provided on the unit. The block is installed on standard frame fixtures and connects to the aircraft wiring through the rear connector Ш1-1.

A-037-1 on Mi-8 / Mi-17 / Mi-171 helicopters

The A-037-1 is widely used in radio altimeter installations on Mi-8, Mi-17 and Mi-171 family helicopters, as well as other aircraft platforms where the A-037 system is installed. On helicopters, the system supports low-altitude awareness during approach, landing, hover, descent, external load operations, flight over water and terrain-clearance monitoring. Exact compatibility should always be confirmed by the helicopter modification, equipment list, wiring diagram and radio altimeter documentation.

Service and installation notes for A-037-1

The A-037-1 must be operated and maintained strictly according to aircraft documentation and radio altimeter technical requirements. Before installation, the unit should be checked for condition, connector integrity, completeness, mounting compatibility, passport data and service history. Since the transceiver is only one part of the system, troubleshooting should include antennas, coaxial lines, cockpit indicators, warning circuits, power supply and interconnecting cables. Reliability limits, service life, environmental conditions and acceptance rules are defined by the manufacturer documentation and confirmed by the product passport.

Identification and supply of A-037-1

For procurement, the full designation A-037-1 should be stated clearly. Alternative spellings such as A037-1, A 037 1 or A-037-1 transceiver may help identify the item in English-language requests, but the exact part number should be used for supply and documentation. In Russian-language documentation, the correct designation is А-037-1. For aircraft use, the unit should be supplied with passport and operation manual when required for acceptance, installation or maintenance records.

Product Name: Radio Altimeter Transceiver
Part Number: A-037-1
Product Type: Radar altitude measuring unit / transmitting-receiving unit
Function: Measurement of true altitude above ground, water or rough terrain
Operating Principle: Continuous-wave radar with frequency modulation
System Application: A-037 radio altimeter set
Operating Altitude Range: 20–700 m
Residual Altitude H₀: 7.2 m
Measurement Error, 95%, H1/H3 outputs up to 20 m: ±0.6 + 0.05·H
Measurement Error, 95%, above 60 m: ±0.6 + 0.05·H
Analog Indication Error, 0–20 m: ±2 m
Calibration Error on K-5 Delay Line, H1/H3 Analog Outputs: ±(0.3 + 0.03·H)
Indicator Calibration Error: ±0.05·H
Overall Sensitivity on K-5 Line: ≥87 dB
Altitude Pulse Outputs, 1RS / 2RS: 5–750 m
Danger-Altitude Signal Error, 0–20 m: ±1 m
Danger-Altitude Signal Error Above 20 m: ±2 m
Aural Signal Duration: 3–9 s
Indicator Backlight: White / red
Control-Mode Altitude Indication: 15 ±2 m
Power Consumption from 115 V, 400 Hz Supply: Up to 10 VA
Power Consumption from 27 V DC Supply: Up to 30 W
Unit Mass: 6.8 ±0.3 kg
Installation / Mounting: Standard frame fixtures; rear connector Ш1-1
Adjustment Access Points: “1RS” and “2RS”
Typical Installation Platforms: Mi-8, Mi-17, Mi-171 helicopters and other aircraft on request
Condition: As applicable
Alternate Designations: A-037-1; A037-1; A 037 1; A-037-1 transceiver
Documentation: Product passport and operation manual

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.