Aviation R&D and testing – measurement solutions

Ground vibration testing (GVT) is a crucial process in aviation R&D and testing, involving both experimental and analytical vibration investigations. This testing is essential for determining the modal characteristics of aircraft structures. By accurately measuring the dynamic response of these structures to various excitation forces, GVT helps identify natural frequencies, mode shapes, and damping properties. This precise data is vital for ensuring the safety, reliability, and performance of aircraft, enabling engineers to validate and optimize structural designs effectively.

Measurement solutions for aviation applications from Kistler include various top-notch single-axis and triaxial accelerometers but also impulse hammers, signal conditioning systems, data acquisition systems and software.

Flight vibration testing (FVT) is a vital procedure in aviation R&D and testing, conducted during actual flight operations to assess the vibrational behavior of aircraft. This testing provides critical insights into how aircraft structures respond to real-world aerodynamic forces and operational conditions. By capturing detailed vibration data, FVT helps identify key modal characteristics such as natural frequencies, mode shapes, and damping ratios. This information is essential for verifying the structural integrity and performance of aircraft, ensuring they meet stringent safety and reliability standards. Engineers use these insights to refine and enhance aircraft designs, contributing to safer and more efficient aviation.

Kistler measurement technologies for aviation R&D and testing include various small and perfectly suitable single-axis and triaxial accelerometers. Operating temperature options range from cryogenic to very high temperatures.

Aircraft landing gear and brake testing are essential procedures to ensure the safety and reliability of aircraft during takeoff, landing, and taxiing. The landing gear must withstand significant impact forces during these operations, particularly during landing when the gear absorbs the aircraft's weight and the kinetic energy of descent. In aviation R&D and testing, these tests evaluate the performance and durability of landing gear components, including struts, wheels, and brakes, under various load conditions. By simulating real-world scenarios, engineers can assess how the landing gear handles these impact forces, ensuring structural integrity and braking efficiency. This rigorous testing helps identify potential issues and ensures that the landing gear can endure the stresses of repeated use, contributing to the safe operation of the aircraft.

Aircraft drop testing is a crucial procedure to evaluate the structural integrity and stress on aircraft components during impact scenarios. In aviation R& D and testing, this testing involves dropping the aircraft or its components from a specified height to simulate real-world impact forces experienced during hard landings or emergency situations. By assessing the dynamic response of the aircraft, engineers can determine how well the structure absorbs and distributes these forces, ensuring that critical components remain intact. Key measurements taken during drop testing include acceleration and impact force measurements, which provide detailed data on how the aircraft responds to the impact. Additionally, drop testing helps evaluate the safety of occupants by analyzing how the impact affects the cabin and seating arrangements. This rigorous testing ensures that aircraft can withstand severe impact conditions, enhancing overall safety and reliability.

In aviation R&D and testing, wind tunnel measurements are essential for understanding the aerodynamic forces acting on aircraft under various flow conditions. By measuring lift, drag, and side forces, engineers gather precise data that are critical for optimizing design and performance. Piezoelectric force sensors are particularly valuable for investigating highly dynamic phenomena due to their high stiffness and natural frequency. Additionally, dynamic wind tunnel measurements help investigate the aeroelastic behavior of structures like wings and control surfaces in critical flow conditions. This involves analyzing how wind causes these structures to deform and oscillate. The detailed data from these measurements is crucial for enhancing the safety, efficiency, and overall performance of aircraft.

Jet engine combustion testing is a critical process in engine development and production, focusing on investigating combustion instabilities in very hot areas. Aviation R&D testing engineers analyze these instabilities to ensure efficient and stable combustion under various operating conditions. Vibration and pressure pulsation measurements are crucial for identifying instabilities that can affect engine performance. These tests are conducted not only during development but also after manufacturing and following major overhauls. By thoroughly testing and analyzing combustion dynamics and vibrations, engineers can enhance the safety, efficiency, and longevity of jet engines.

Battery thermal runaway testing is crucial for the safety and reliability of electric airplanes and eVTOLs. In aviation R&D and testing, this procedure involves investigating the pressure behavior during a thermal runaway process of a battery cell or module. By understanding how pressure builds and behaves during such events, engineers can optimize the design of battery modules. This includes refining the shape, material thickness, and ventilation paths to mitigate risks and enhance safety. Thorough testing and analysis help ensure that battery systems can withstand extreme conditions, contributing to the overall safety and performance of electric aviation.

Bird strike testing is essential for ensuring the safety and durability of aircraft structures and components. This testing involves measuring the impact forces and investigating the behavior of aircraft components when struck by birds. By simulating bird impacts, aviation R&D and testing engineers can assess how different parts of the aircraft, such as the fuselage, wings, and engines, respond to these dynamic forces. Piezoelectric force sensors, with their high stiffness and resulting high natural frequency, provide precise measurements, helping engineers identify design weaknesses. This helps optimize the structural integrity and resilience of aircraft, ensuring they can withstand such impacts and maintain safety during flight.

Electric aircraft propulsion testing is crucial for characterizing the performance of the propulsion system, from the electric motor to the propeller. This involves measuring the rotational torque and speed to ensure optimal efficiency and reliability. An additional dynamometer setup allows for comprehensive testing by also measuring forces and moments in all directions generated by the propeller. This setup helps aviation R&D and testing engineers analyze the propulsion system's behavior under various operating conditions, ensuring that electric airplanes and eVTOLs can perform safely and efficiently. By thoroughly testing and characterizing the propulsion system, engineers can optimize design and performance, contributing to the advancement of electric aviation technology.

Highly Accelerated Life Testing (HALT) and Highly Accelerated Stress Screening (HASS) are critical processes in the aviation R&D and testing for validating design criteria during aircraft component development. These tests, which are part of environmental stress screening (ESS), combine extreme thermal and vibration stress to identify potential weaknesses and ensure the reliability and durability of components over their entire lifecycle.
Lightweight accelerometers with high temperature stability are crucial for accurately measuring the dynamic responses during HALT and HASS testing. By subjecting components to these rigorous tests, engineers can detect and address design flaws early in the development process, enhancing the overall safety and performance of aircraft. This thorough validation helps ensure that aircraft components can withstand the demanding environments they will encounter in service.

Hydraulic systems are crucial for aircraft operations, including flight controls, landing gear, and braking systems. In aviation R&D the testing of these systems involves measuring static and dynamic pressures under various conditions to ensure reliability and safety. Hydraulic devices like pumps, actuators, and control surfaces convert flight commands into real-time actions, directly impacting flight safety. 
High-performance pressure sensors for aviation applications, such as piezoresistive sensors, are essential for evaluating these pressures. These sensors offer high stability and repeatability, making them ideal for harsh aviation environments with temperature extremes, high vibration, and shock levels.

Actuator testing is essential in aviation R&D and testing to ensure the proper functioning and reliability of actuators that control critical flight surfaces such as flaps, ailerons, and rudders. These actuators are responsible for executing precise movements that directly impact an aircraft's performance and safety.
To validate actuator performance, force sensors and reaction torque sensors are employed to measure the forces and torques generated during operation. Additionally, DC-response accelerometers are used to accurately identify the position of the actuators, ensuring they respond correctly to control inputs. This thorough testing ensures that actuators will perform reliably under various flight conditions, contributing to the overall safety and efficiency of the aircraft.

Crash testing in aviation is a critical process for enhancing the safety and survivability of aircraft. In aviation R&D and testing, these tests simulate severe but survivable crash scenarios to evaluate how aircraft structures respond to impact forces. A key component of these tests is the use of crash test dummies, which are equipped with sensors to measure the forces experienced during a crash.
Engineers conduct various crash tests, including dropping sections of airplane fuselages or entire aircraft from significant heights. These tests help gather data on how the airframe behaves, how it collapses, and how much load is transferred to the occupants. The crash test dummies are fitted with measurement technologies for aviation testing such as accelerometers and load cells to measure variables such as g-forces, head and neck movement, and spinal compression. The data collected from these tests is crucial for improving aircraft design to minimize injury risks during crashes.

In aviation R&D and testing, machining research is vital due to the use of new and lightweight materials that enhance aircraft performance. These advanced materials often require specialized tools and machining processes to achieve the desired quality and precision. By analyzing cutting processes such as turning, milling, and drilling, researchers can develop tailored solutions for these materials. 
Piezoelectric dynamometers, both stationary and rotating, are used to measure the forces and moments involved in machining. This sensor technology allows for very dynamic measurements due to its high natural frequencies. The insights gained from this research are crucial for developing and assessing tools and materials that ultimately contribute to the high quality and durability of critical aircraft components.

The wing up bend test is a crucial procedure in aviation R&D and testing to assess the structural integrity and flexibility of aircraft wings. This test involves applying significant upward forces to the wings to simulate the stresses they would encounter during flight, particularly during maneuvers and turbulence. In this test, the aircraft wing is securely anchored, and a rope system is used to apply upward loads to the wings. The ropes are attached to the wings and connected to a winch or pulley system that gradually increases the tension. The goal is to observe how the wings deform and to identify any potential structural weaknesses. Piezoelectric force sensors are an excellent choice for this application due to their ability to cover a wide measuring range and their very long service life.