DESCRIPTION

Aircraft on the ground require a clean, stable power supply to run avionics, environmental control systems, lighting, and other on-board electrical systems without relying on the aircraft’s own engines or APU. Running the APU for extended periods during turnaround, maintenance, or overnight parking burns fuel, generates noise, and produces emissions. A diesel ground power unit eliminates all of this by delivering the precise 400 Hz AC and 28 VDC power that aircraft systems require, directly from a mobile unit that can be positioned at any stand or remote parking position.

The FCA series by TET Estel is a modular DGPU built around three core components: a Cummins diesel generator set, the FCA frequency converter module (50 Hz to 400 Hz), and the AR-1x600D rectifier module (28 VDC output). This modular architecture means each subsystem can be maintained or serviced independently, reducing downtime and simplifying parts management.

The 400 Hz output is where precision matters most. Aircraft electrical systems are designed for tight voltage and frequency tolerances, and any deviation can affect avionics performance or trigger fault warnings. The FCA converter delivers frequency stabilisation accuracy of ±0.1% and voltage regulation accuracy of ±0.5%, with total harmonic distortion (THD) below 2% and voltage modulation below 1%. These figures meet or exceed the requirements of DFS 400, ISO 6858, MIL-704E, and SAE ARP 5015, ensuring compatibility with all commercial and military aircraft types.

The FCA-90 delivers 90 kVA of 400 Hz power from a single converter output, while the FCA-180 provides 180 kVA through two parallel 90 kVA modules. This scalable approach means the FCA-180 handles wide-body aircraft and simultaneous multi-system loads, while the FCA-90 covers narrow-body turnarounds and maintenance operations at a lower weight and fuel consumption.

The 28 VDC module delivers 600 A continuous with output voltage stabilisation accuracy of 0.85% and voltage ripple of just 1%. The adjustable output voltage range of 19 to 33 V accommodates different aircraft bus voltage requirements, and the unit can handle surge loads of up to 2,400 A for 2 seconds, providing the current needed for engine starting.

Both models can switch between diesel generator mode and external grid mode (3x400V, 50 Hz). In static mode with external power, the units support significant overload capacity: 150% for 600 seconds, 200% for 30 seconds, and up to 400% for 2 seconds. This flexibility means the same unit can operate as a mobile GPU on the apron and as a fixed-position converter when connected to shore power in a maintenance hangar.

The diesel generator sets use Cummins engines: the QSB6.7-G32 (150 kW / 188 kVA) for the FCA-90, and the QSL8.9-G30 (250 kW / 313 kVA) for the FCA-180. Both are 6-cylinder, turbocharged, liquid-cooled engines running at 1,500 RPM with electronic governing. The Cummins platform provides a global service and parts network, which is a practical consideration for airports operating equipment across multiple locations.

The self-propelled chassis reaches a maximum speed of 25 km/h, allowing the unit to transit between stands and parking positions without a tow vehicle. The fuel capacity is 2×150 litres on the FCA-90 and 2×300 litres on the FCA-180, providing extended autonomous operation for busy turnaround schedules. The operating temperature range covers -40°C to +40°C, and the IP55-rated converter module protects the power electronics against water jets and dust ingress in exposed apron environments.