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The sBOOMTraj tool offers an updated approach to accurately predict sonic boom ground signatures for supersonic aircraft. The tool is based on the numeric solution of the augmented Burgers equation where the regular Burgers equation is augmented with absorption, molecular relaxation, atmospheric stratification, and ray tube spreading terms in addition to the non-linear term from the regular equation. The primary idea behind such augmenting is that atmospheric losses are captured, which results in more realistic sonic boom predictions compared to linear theory methods. While previous iterations of the software (sBOOM) were limited to single point analysis (i.e., a point in supersonic climb or cruise), sBOOMTraj extends the prediction of sonic boom to multiple points along the supersonic mission. This includes updated functionality to handle aircraft trajectories and maneuvers as well as inclusion of all relevant noise metrics. The improvements allow efficient computation of sonic boom loudness across the entire supersonic mission of the aircraft. The sBOOMTraj tool can predict ground signatures in the presence of atmospheric wind profiles, and can even handle non-standard atmospheres where users provide temperature, wind, and relative or specific humidity distributions. Furthermore, sBOOMTraj can predict off-track signatures, ground intersection location with respect to the aircraft location, the time taken for the pressure disturbance to reach the ground, lateral cut-off locations, and focus boom locations. The software has the ability to easily interface with other stand-alone tools to predict the magnitude of focus, post-focus, and evanescent booms, and also has the ability to handle different kinds of input waveforms used in design exercises. The sBoomTraj tool could be extremely useful in supersonic aircraft operations as it can predict where sonic booms hit the ground in addition to providing the magnitude of sonic boom loudness levels using physics-based simulations. Using this tool, pilots may be able to steer supersonic aircraft away from populated areas while also allowing real-time adjustments to their flight trajectories, allowing trade-offs associated with sonic boom, performance and acceptability. The predicted sonic boom loudness contours during supersonic flight may also be used in supersonic aircraft design and development, including certification of aircraft under future regulations that may be imposed. sBOOMTraj offers a revolutionary approach to mitigating sonic boom through its unique sonic boom adjoint equations. This potentially has immediate and realizable benefits in supersonic aircraft design when integrated with other disciplines. The NASA technology can potentially aid in supersonic aircraft operations with its integration in a cockpit interactive application that can provide feedback to the pilot on sonic boom impingement areas on the ground with real-time atmospheric and terrain updates. sBOOMTraj has the potential to support both aircraft design and operations, which is extremely rare.

Deployable composite booms are particularly attractive in space constrained applications. Their high packaging volume efficiency enables relatively large spacecraft systems required for power generation, communications, or propulsion to be housed within small volumes. COROTUB is a monolithic closed-section tubular thin-shelled structure thats been shown to scale efficiently up to 50m yet maintain its strength. COROTUBs two corrugated thin shells form a closed section, which yields high bending and torsional stiffness, allowing for high dimensional stability. Computational analysis and early tests show that the corrugation provides increased strength against buckling, enabling longer booms and targeting more demanding structural applications than non-corrugated designs. The corrugation geometry that dictates the boom cross-section shape was informed by parametric studies to optimize the parameters that most influence the cross-sections area moment of inertia and torsional constant. The corrugated designs were found to improve the boom bending and axial strength and to shorten the length of the boom transition from flat/rolled to deployed.

The new SMC substrate has four components: a shape memory polymer separately developed at NASA Langley; a stack of thin-ply carbon fiber sheets; a custom heater and heat spreader between the SMC layers; and integrated sensors (temperature and strain). The shape memory polymer allows the as-fabricated substrate to be programmed into a temporary shape through applied force and internal heating. In the programmed shape, the deformed structure is in a frozen state remaining dormant without external constraints. Upon heating once more, the substrate will return slowly (several to tens of seconds) to the original shape (shown below). The thin carbon fiber laminate and in situ heating solve three major pitfalls of shape memory polymers: low actuation forces, low stiffness and strength limiting use as structural components, and relatively poor heat transfer. The key benefit of the technology is enabling efficient actuation and control of the structure while being a structural component in the load path. Once the SMC substrate is heated and releases its frozen strain energy to return to its original shape, it cools down and rigidizes into a standard polymer composite part. Entire structures can be fabricated from the SMC or it can be a component in the system used for moving between stowed and deployed states (example on the right). These capabilities enable many uses for the technology in-space and terrestrially.