T-M400C in Portugal: Tethered Drone Cleaning for Building Facades

A customer in Portugal recently introduced the T-M400C dual-tethered drone cleaning system into its exterior building maintenance workflow. The system is being used to clean building facades, demonstrating how tethered drone technology can support practical high-altitude cleaning operations.

By combining continuous power with a ground-supplied high-pressure cleaning system, the T-M400C enables operators to reach elevated exterior surfaces while remaining on the ground.

What Cleaning Challenge Did the Customer Face?

Cleaning a building facade becomes increasingly difficult as the working height and surface area increase. Conventional approaches may require scaffolding, lifting platforms, cranes, or rope-access technicians, all of which can add preparation time, equipment requirements, and operational complexity.

The Portuguese customer needed a solution that could reach elevated sections of the building exterior while delivering sufficient water pressure for effective surface cleaning.

The T-M400C was selected to bring the cleaning equipment directly to the target area using a DJI Matrice 400 drone.

How Was the T-M400C Used in This Project?

During the operation, the DJI Matrice 400 carried the lightweight aerial spray gun along the building facade. Water was supplied continuously from the ground through the tethered hose, allowing the operator to clean different exterior sections without relying on a small airborne water tank.

The system supports a cleaning altitude of up to 60 meters and uses an 80-meter lightweight water hose, giving the drone sufficient working range for many residential, commercial, and industrial buildings.

Different spray nozzles can also be selected according to the target surface and cleaning requirements. This allows the operator to adjust the spray pattern for concentrated cleaning or broader facade coverage.

Why Is the Dual-Tethered Design Important?

The T-M400C uses separate tethered systems for power and water supply.

Its tethered power system provides the DJI Matrice 400 with continuous power for extended operations, reducing the interruptions normally associated with frequent battery replacement. The system can supply power for up to eight hours per operation, although landing and resting for one hour after four hours of continuous cleaning is recommended.

At the same time, the ground-based high-pressure washer supplies water through the tethered hose. With 110–160 bar pressure and a flow rate of up to 500 L/h, the system can support demanding exterior cleaning tasks without requiring the drone to carry a heavy water tank.

How Does It Improve the Facade Cleaning Workflow?

For the Portuguese customer, the T-M400C provides a more flexible way to approach elevated building surfaces.

The complete system can be prepared for operation in under ten minutes, helping reduce the time required to begin a cleaning task. Once deployed, the drone can move between different facade sections while the operator monitors the flight and controls the cleaning direction from the ground.

This workflow can reduce dependence on large access equipment for suitable projects and limit the need for workers to remain directly exposed to elevated working environments. Actual deployment must still consider the building structure, weather, local drone regulations, surrounding pedestrians, and site-specific safety requirements.

What Does This Portuguese Customer Case Demonstrate?

This application shows how the T-M400C can move beyond product testing and become part of a real building-maintenance workflow.

For facade cleaning companies, property maintenance teams, and aerial service providers, the system offers a practical combination of high-pressure cleaning, extended operating time, and aerial access. It can be considered for exterior walls, glass curtain walls, tiled surfaces, and other elevated architectural facades within its supported working range.

The Portuguese project also demonstrates the growing potential of tethered drones in professional cleaning services. By bringing cleaning equipment directly to difficult-to-reach surfaces, the T-M400C helps service providers approach high-altitude facade maintenance with greater flexibility while keeping the primary operators on the ground.