Aerospace Manufacturing How Sonplas transfers automotive test expertise into next-generation aerospace fuel-system validation

Sonplas, a German specialist in customised assembly and test equipment, is expanding its long-standing automotive know-how into aerospace Maintenance, Repair and Overhaul (MRO). With flexible test benches for fuel and hydraulic components, the company enables precise, realistic and automated testing of safety-critical systems used in commercial and military aviation.

For more than 30 years, Sonplas has developed assembly and test systems for high-precision, fuel-carrying components in the automotive industry — including injectors, valves, pressure regulators, distribution rails and fuel pumps.
“Many of these components also exist in aerospace, just larger and operating at higher pressures and flow rates,” explains Matthias Kraml, Sales Engineer at Sonplas.Since 2014, the company has been applying its automotive expertise to aerospace MRO, developing flexible test concepts for hydraulic and fuel-system components. The systems enable precise regulation of pressure and flow while allowing manufacturers and MRO providers to test a broad variety of pump types on a single platform.

Realistic simulation for safety-critical components

Sonplas designs test benches for a wide range of aerospace fuel components, including pumps, and offers configurable test and environmental conditions. Flow, pressure and leakage can be measured hydraulically to customer specifications. Combined air- and fluid-testing capabilities, automated calibration cycles and cleaning processes enable complete functional checks in a single system.
The company also offers spray-test stands that analyse the angle and width of fuel-nozzle spray patterns — essential for combustion quality and engine safety.A dedicated in-house development laboratory supports feasibility studies, product testing, temperature evaluations and injection-rate measurements. Both functional and endurance tests can be carried out on individual components or complete systems, strictly following customer requirements defined in the Component Maintenance Manual (CMM).

Environmental and safety testing

To ensure components withstand the extreme conditions experienced in flight, Sonplas integrates environmental simulation into its systems. Climate chambers replicate temperature, humidity and pressure variations; vibration testing is also possible.For components used in potentially explosive atmospheres — such as fuel tanks or during the handling of flammable liquids — Sonplas develops solutions compliant with ATEX and IECEx standards. This includes consulting, engineering and operational support for explosion-protected systems.

Successful implementations in major aerospace programmes

Sonplas has already delivered several notable aerospace projects. One example is the highly complex main fuel pump used on the Boeing 777 engine, which weighs nearly 30 kilograms and required a flow rate of 650 litres per minute (170 gal/min).
“Our experience from other pump sectors was crucial,” says Kraml. The test stand identifies and adjusts the component automatically, performs all required test steps and accommodates up to 15 different engine models.The company’s expertise is also used for centre- and wing-tank pumps, where flow rates can reach up to 900 litres per minute — several times higher than in automotive applications.

Customised system design instead of standard solutions

As a specialist in bespoke machinery, Sonplas develops test concepts jointly with customers and adapts them precisely to individual requirements. This includes systems for complete pumps, single components such as overpressure valves, or combined configurations.
Automotive-level automation, including automatic recognition, clamping, calibration and test sequences, is increasingly being transferred to aerospace — a sector where such automation has not traditionally been common.Sonplas also supports the optimisation of existing MRO lines, integrating multiple procedures into one system where needed.

Integrated assembly and test from a single provider

With assembly and test engineering under one roof, Sonplas offers customers a single point of contact and access to a strong network of certified suppliers. Standard components are integrated where suitable, while proprietary developments are used when custom requirements exceed the limits of off-the-shelf solutions.This makes the company’s systems scalable, cost-efficient and highly adaptable.
“We know exactly what matters in these components,” says Kraml. “That puts us on equal footing with our customers — and creates real value.”Through its tailored, cross-industry approach, Sonplas has become established in demanding sectors such as automotive and aerospace. The transferability of its technology also opens opportunities in medical technology, semiconductor manufacturing and energy systems.