Static Firing Tests of Solid Propellant Rocket Motors: Uncertainty Levels of Thrust Measurements

Abstract

Static firing tests of solid propelled rocket motors (SRMs) are important tests in aerospace industry during the development of new motors as well as to assure the quality of a motor batch. This type of test allows the operator to obtain the measured "thrust versus time of burning" graphic yielded by the motor during burning to verify whether the motor performance matches the project requirements. Laboratory Quality Certificates and good measurement practices make necessary the evaluation of the typical uncertainty of these test results, which demand a wide number of instruments, called measurement chain. This work aims to present the uncertainty levels expressed to the thrust values gathered during a SRM static firing test for two differently configured measurement chains. In order to estimate the uncertainty of a complete measurement chain, the theories of expanded and combined uncertainties are employed. It was possible to verify that in the analyzed case the use of signal amplifiers increased the measurement uncertainty of the chain.

Structural Health Monitoring of Solid Rocket Motors: From Destructive Testing to Perspectives of Photonic-Based Sensing

“…Pressure tests help in the identification of the SRM's structural limits and the observation of failure mechanisms such as rupture, debonding, delamination, or buckling [17]. Static test firing allows for the measurement of thrust, chamber pressure, and burn rate, providing information on the motor's performance and enabling the validation of design predictions [18].…”

“…Pressure tests help in the identification of the SRM's structural limits and the observation of failure mecha nisms such as rupture, debonding, delamination, or buckling [17]. Static test firing allow for the measurement of thrust, chamber pressure, and burn rate, providing information on the motor's performance and enabling the validation of design predictions [18]. In general, destructive testing processes are assisted by strain gauges, which are used to measure structural deformation and stress distribution during destructive testing, and high-speed imaging digital cameras or video recorders, which capture the dynamic be havior of the SRM during testing.…”

Impact Point Dispersion Prediction for 300 mm R-Han 300 Artillery Rocket

“…Atmospheric conditions that are always changing cause uncertainty in measurement of atmospheric parameter (Trzun and Vrdoljak 2020). Production process of solid propellant is a source for variations of thrust curve (Fernandes, Sauto, and Pirk 2020).…”