Many rocket motors used by the Navy are powered using solid rocket propellants (SRP). Over time and with exposure to varying environmental conditions, the elastomeric binder material undergoes oxidative degradation leading to embrittlement of the SRP. Current methods of non-destructive testing (NDT) using ultrasound exist to inspect SRPs for major defects that occur when aged SRPs exhibiting such brittleness experience failures such as, large cracks, fissures, and delamination in normal transportation, storage, and operating situations. However, these methods do not provide a mode of inspection to reliably detect changes in the mechanical integrity of the propellent prior to the point of failure. METSS is proposing an optimized method of ultrasonic NDT to detect and correlate aging with mechanical degradation of SRP materials. Monitoring changes in ultrasonic wave velocity is a well-supported method of detecting aging in SRP. METSS seeks to fill the technology gap by connecting ultrasonic measurements to mechanical degradation and integrating it with a compact, field deployable system focusing on ease of use for a single operator. This will allow for fast, efficient, and accurate field testing of the SRP motors to monitor propellent properties that could lead to mechanical failure or alter the response of the propellant.
Benefit: A man-portable ultrasonic solid propellent inspection system will allow the Navy to easily evaluate the mechanical integrity of solid rocket propellants (SRP) in the qualifying phase and once deployed. This compact, deployable system allows a single operator to inspect SRPs in forward operating and austere environments where aging of the propellant may be accelerated by fluctuations and/or extremes in climate. The resulting data will provide the operator with means to monitor the aging process and better predict the service life of the SRP and ensure that only mechanically sound SRPs are used. Solid rocket propellant motors are used widely in military and space propulsion applications, as well as a growing commercial sector. The product uses vary widely to include suborbital rockets used to gather meteorological data on earths upper atmosphere, to orbital rockets that deploy small satellites, to ballistic missiles used in defense. METSSs system has commercialization potential with any of these products. Additionally, ultrasonic NDT already has a strong foothold in aerospace, automotive, energy, manufacturing, and oil and gas industries. METSS recognizes there is a market need for NDT testing with a greater degree of precision and functionality allowing for discreet inspection of aged elastomeric materials.
Keywords: Man-Portable, Man-Portable, Neural network, ultrasonic, rocket motor, Non-destructive Testing, Material Properties, Solid Propellant
