Sentronics releases UAV fuel-flow sensors

Sentronics has released the RealFlow D-Series, a range of configurable ultrasonic fuel-flow sensors developed for commercial and defence UAV platforms.

The sensors are designed to deliver laboratory-grade fuel-flow measurement in dynamic flight environments, where vibration, acceleration, temperature change, and rapidly changing flow conditions can disrupt conventional measurement techniques. The range covers flow rates from 20ml/min to 20l/min, allowing manufacturers and integrators to match sensor selection to engine size, platform class, and mission profile.

The D-Series uses a patented measurement algorithm and contains no moving parts. The inline architecture provides zero flow impedance and pressure drop, supporting integration into compact UAV fuel systems without adding mechanical complexity. Measurement accuracy is better than ±0.75% of reading across a wide range of flow rates, fluid temperatures, and fuel compositions.

Multi-fuel compatibility allows operation with gasoline, kerosene, diesel, Jet-A1, and JP fuels without recalibration or fuel-specific components. The sensors are designed around a low-SWaP footprint and are engineered to meet relevant military environmental and EMC standards. The product line follows the earlier debut of the d450 and d600 models at DSEI 2025.

Fuel-flow measurement is becoming a more demanding subsystem as UAV missions extend beyond short-range operations. Long-endurance surveillance, logistics, border monitoring, maritime patrol, and hybrid-electric aircraft all depend on accurate fuel and energy modelling. Uncertainty in consumption affects range prediction, reserve planning, route optimisation, payload decisions, and mission abort thresholds.

Defence UAVs also require fuel data that remains accurate under real flight conditions. Consumption can change quickly during climb, manoeuvre, loiter, payload operation, or generator loading in hybrid-electric systems. Static bench performance does not capture every condition encountered in service, especially on platforms exposed to vibration, acceleration, rapid throttle changes, and harsh environmental conditions.

The expansion of small tactical UAVs and heavier uncrewed aircraft is widening the range of fuel-system requirements. A compact drone may need a lightweight sensor with minimal pressure drop, while a larger surveillance or cargo platform may require higher flow capability and more robust environmental performance. A configurable sensor range allows integrators to use a common measurement approach across multiple aircraft classes.

The absence of moving parts reduces wear, pressure loss, maintenance demand, and measurement drift. Ultrasonic sensing also avoids some of the mechanical limitations associated with turbine or positive-displacement flow meters, provided signal processing remains stable across fuel types and dynamic flow conditions. For aircraft operating in remote or demanding environments, lower maintenance and consistent measurement can support availability as well as mission planning.

Sentronics’ background in motorsport fuel measurement gives the technology a demanding development base. Motorsport and UAVs both require compact, high-accuracy sensing under vibration and changing operating conditions, although certification environments and duty cycles differ. That experience transfers naturally into unmanned aircraft, where performance margins are often tight and system weight remains heavily constrained.

As UAVs take on longer missions and more complex power architectures, fuel measurement is moving beyond auxiliary instrumentation. Accurate flow data can support control strategies, validation programmes, endurance prediction, and hybrid-electric energy management. The RealFlow D-Series gives aircraft designers a sensor option built around those operating conditions rather than adapted from less dynamic fluid measurement environments.