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Karen Berger

Publications and source records attributed to Karen Berger.

Tile Surface Thermocouple Measurement Challenges from the Orbiter Boundary Layer Transition Flight Experiment

Hypersonic entry flight testing motivated by efforts seeking to characterize boundary layer transition on the Space Shuttle Orbiters have identified challenges in our ability to acquire high quality quantitative surface temperature measurements versus time. Five missions near the end of the Space Shuttle Program implemented a tile surface protuberance as a boundary layer trip together with tile surface thermocouples to capture temperature measurements during entry. Similar engineering implementations of these measurements on Discovery and Endeavor demonstrated unexpected measurement voltage response during the high heating portion of the entry trajectory. An assessment has been performed to characterize possible causes of the issues experienced during STS-119, STS-128, STS-131, STS-133 and STS-134 as well as similar issues encountered during other orbiter entries.

Charles H. Campbell↗

NASA Langley Aerothermodynamics Laboratory: Hypersonic Testing Capabilities

A description of the NASA Langley Research Center’s Langley Aerothermodynamics Laboratory (LAL) will be presented in the paper, along with descriptions and details of the facility test techniques and recent upgrades. The LAL consists of three hypersonic blow-down wind tunnels covering Mach numbers of 6 and 10 and unit Reynolds number ranges of 0.5 to 8.3 million per foot as well as a 60-ft Vacuum Sphere Test Chamber. LAL facilities are used to study and define the aerodynamic performance and aeroheating characteristics of flight vehicle concepts. Data collected in the facilities have been used for design and optimization, anchoring computational predictions, generation of aerodynamic databases and design of Thermal Protection Systems. Over the years modifications and enhancements have been made to the facility hardware and instrumentation to increase efficiency, data quality, capabilities and reliability to better meet the programmatic requirements. Recent utilization information illustrates the need for the capabilities associated with these facilities. Recent test programs include the Space Shuttle Program, Crew Exploration Vehicle/Orion/Multi-Purpose Crew Vehicle, Hypersonic International Flight Research Experimentation (HIFiRE), Mars Science Laboratory, Hypersonic Inflatable Aerodynamic Decelerator System (HIADS) and X-51 among others and usage has been split between NASA, Commercial Crew, Department of Defense and private company programs. Plans for future improvements to the facility infrastructure and instrumentation will also be presented.

Karen Berger↗