PMK-21

PMK-21 System Overview

The PMK-21 is an aircraft electromechanical program mechanism designed for control of anti-icing systems within helicopter onboard equipment. The unit functions as a programmed switching device integrated into blade heating system architecture.

PMK-21 Control Function

The mechanism provides sequential switching of heating elements in an impulse mode, ensuring controlled distribution of electrical power between sections of rotor and tail rotor blade heating systems according to a predefined timing program.

PMK-21 Aircraft Application

The unit is used on helicopters equipped with anti-icing systems, including Mi-8 family helicopters, where it ensures protection of rotor blades against icing during operation in adverse weather conditions.

PMK-21 System Integration

The mechanism operates in conjunction with onboard power supply systems and anti-icing control units, receiving AC power and distributing it cyclically to heating circuits. The product is also known under alternative designation PMK-21.

Product Type: Electromechanical program mechanism
Function: Sequential control of blade heating elements in anti-icing systems
Application / Where Used: Helicopter anti-icing systems
System / Installation Area: Rotor and tail rotor blade heating system
Compatible Aircraft / Equipment: Mi-8 family helicopters and similar platforms
Operating Voltage: 208 V AC
Frequency: 400 Hz
Power Source: Aircraft AC generator (e.g., SGO-30U)
Control Principle: Programmed cyclic switching (impulse mode)
Controlled Circuits: Rotor blade heating elements; tail rotor blade heating elements
Operating Mode: Cyclic sequential activation of heating sections
Construction Type: Electromechanical cam-based program mechanism
System Integration: Interfaces with onboard electrical and anti-icing control systems
Technical Documentation: Product passport and operational documentation

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.