748A

748A fuel pump for the KO-50 heater

The 748A is an electrically driven aircraft fuel pump used in the fuel circuit of the KO-50 kerosene heater. Its job is straightforward: to deliver aviation kerosene to the heater and keep the fuel pressure within the operating range required for start-up and steady combustion. In the KO-50 system, the pump is not an auxiliary detail somewhere on the line; it is one of the main units that makes the heater work correctly. If fuel delivery is weak or unstable, the heater may fail to start, run unevenly, or shut down through the protection logic.

Fuel delivery role of the 748A in operation

During heater start-up, the 748A supplies fuel to the KO-50 fuel system so that ignition and combustion can begin under controlled conditions. After the heater reaches operating mode, the pump continues to maintain delivery to the fuel equipment. The flow must be stable enough for the heater to operate without interruptions, but not excessive for the downstream components. This balance is especially important in cold-weather operation, where the heater is expected to start reliably and keep working for cabin heating, ventilation heating, or other aircraft heating requirements.

Pressure control in the KO-50 circuit with the 748A

The 748A also supports pressure stabilization in the heater fuel system. Fuel supplied by the pump enters the KO-50 fuel circuit at the required pressure, while excess fuel is not forced into the heater combustion process. Instead, the surplus is returned through a bypass line. On Mi-8 family helicopters, this excess fuel is drained to the right fuel tank. This arrangement keeps the line from being overloaded and helps the fuel system maintain predictable pressure during the heater operating cycle.

748A with valves and heater automation

The 748A works together with the other fuel-control and automation components of the KO-50 heater. These may include electromagnetic fuel valves, thermal switches, ignition components, relays, and protection circuits. The pump supplies fuel, while the automation decides when the system should ignite, continue working, or stop fuel delivery. For this reason, a fault in the pump can look similar to a valve, wiring, or heater-control issue. In maintenance, the pump should be checked together with the fuel line layout, electrical supply, and the control logic of the installed KO-50 system.

Electric drive of the 748A pump

The 748A is driven by a DC electric motor and operates from the aircraft DC power supply. The electric drive allows the pump to be switched on and off by the heater control system without manual operation. For reliable work, both sides of the unit matter: the electrical part must receive proper voltage and the hydraulic part must create the required pressure and flow. A pump can appear electrically serviceable but still fail to deliver enough fuel because of internal wear, contamination, storage condition, or mechanical restriction.

Aircraft application of the 748A pump

The 748A is mainly associated with the KO-50 kerosene heater used on Mi-8, Mi-17, Mi-171, and related helicopter versions, depending on the installed heating system. The pump is part of the aircraft heating and ventilation equipment rather than the main engine fuel system. Its exact installation must be checked against the helicopter parts catalog, the KO-50 technical documentation, and the fuel system schematic. This is important because heater installations and fuel-line routing can differ between aircraft versions, production batches, and modernization programs.

Ordering and documentation for 748A

When ordering or replacing the unit, the designation 748A should be stated clearly. It is also useful to specify the required condition: new, from storage, repaired, overhauled, or serviceable with documents. Before installation, the pump should be inspected for condition of the housing, connector, inlet and outlet fittings, signs of corrosion, storage damage, and cleanliness of the fuel ports. For aircraft use, the pump should be supplied with the available technical documentation, passport, label, or other quality documents depending on stock condition.

Product Type: Electrically driven aircraft fuel pump
Model / Designation: 748A
Function: Fuel supply and operating pressure maintenance in heater fuel systems
Application / Where Used: Aircraft heating and ventilation systems
System / Installation Area: KO-50 kerosene heater fuel circuit
Associated Equipment: KO-50 aircraft kerosene heater
Compatible Aircraft / Equipment: Mi-8, Mi-17, Mi-171 and related helicopter versions depending on KO-50 installation
Working Medium: Aviation kerosene
Drive Type: DC electric motor
Power Supply: 27 V DC ±10%
Fuel Flow Rate: 15 ±5 kg/h
Inlet Pressure: 1–2.5 ata
Outlet Pressure: 2 ±0.5 kgf/cm²
Excess Fuel Drain: To the right fuel tank through bypass / return line
System Role: Fuel delivery and pressure stabilization in the KO-50 heater fuel system
Design: Aviation-grade electrically driven pump assembly
Weight: Not more than 3.5 kg
Condition: As applicable
Availability: Available upon request
Technical Documentation: Technical documentation available upon request

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.