Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.
Commercial Space Operations Noise and Sonic Boom Measurements 5 1 Introduction Background Commercial space is an emerging and evolving market[1] as evidenced by the vast array of launch vehicles under development. In addition to conventional vertical launch vehicles, current and planned types of commercial space vehicles include rocket planes, air-launched spacecraft, and reusable launch vehicles that perform vertical landings, as shown in Figure 1. Figure 1. Launch vehicle operation types. To support the growing diversity of launch vehicles and operations, the number of active and proposed launch sites and spaceports throughout the U.S. continues to increase. Historically, three federally-owned coastal spaceports â Vandenberg Air Force Base (VAFB), Kennedy Space Center (KSC), and National Aeronautics and Space Administration (NASA) Wallops Flight Facility â have fulfilled the majority of all government and commercial launch needs. As commercial entities explore new vertical and horizontal launch and landing operations, launch facilities are being established closer to communities throughout the United States. As seen in Figure 2, dual-use air and spaceports are becoming more common, signaling a rising interest among airport administrators seeking to invest in the commercial space industry. Federal Aviation Administration (FAA) regulations require all new spaceports and launch vehicles to acquire a license, which requires environmental review. These reviews must include evaluations and assessments of potential noise and sonic boom impacts to the environment and local communities. Accurate predictions of the noise exposure from launch vehicles requires models that have been validated over a range of vehicle types, operations, and atmospheric conditions. However, no robust measured dataset exists to complete a full validation of these models. Therefore, high-fidelity databases of acoustic measurements are needed to verify community noise exposure prediction models and methods.
Commercial Space Operations Noise and Sonic Boom Measurements 6 Figure 2. Active and proposed U.S. launch sites and spaceports for commercial, government, and private use (FAA/AST 2018).
Commercial Space Operations Noise and Sonic Boom Measurements 7 Research Approach The objectives of the research and development project described herein are the following: ï Conduct a literature review of existing rocket propulsion noise and sonic boom measurements and compile the identified resources into a database. ï Develop a community noise measurement protocol for commercial space operations propulsion noise and sonic booms. ï Conduct a measurement campaign to obtain high-fidelity rocket propulsion noise and sonic boom signatures along with supporting operational data from a diverse set of commercial space vehicles and operations. Incorporate the high-fidelity data into the database of existing measurements. This overall research approach is summarized in Figure 3. The database of rocket propulsion noise and sonic boom measurements developed as part of this research effort will serve as model source characteristics for the purpose of facilitating community noise model development and validation. Figure 3. Research approach overview for ACRP 02-81. The systematic review of existing literature focused on identifying, evaluating, and compiling all research relevant to propulsion noise and sonic boom measurements of commercial space operations. A summary of the existing rocket propulsion noise and sonic boom measurement data sources that may contribute to community noise model development and validation is provided in Section 2. The data quality of these
Commercial Space Operations Noise and Sonic Boom Measurements 8 existing published measurements was assessed based on the desired data fidelity and documentation criteria required for model development and validation. All literature sources that were included in the compiled database, including books, journal articles, dissertations, conference proceedings, and government technical documents, will be made accessible to the general public. The community noise measurement protocol, which is provided in Section 3, defines the methods necessary to fully characterize and quantify the propulsion noise and sonic booms produced by commercial space operations. The protocol addresses multiple important elements, including acoustic instrumentation, measurement site specifications, weather measurement and weather limits, data analysis, standard data formatting and organization, and data reporting. Standard measurement procedures, instrumentation, and layouts specific to different commercial spacecraft measurement scenarios (e.g., launch propulsion noise and landing sonic boom) are detailed to inform measurements performed during the ACRP 02-81 measurement campaign effort as well as future measurements. The measurement campaign was designed to acquire high-fidelity rocket propulsion noise and sonic boom measurements based on the community noise measurement protocol. Measurements of four different space operations events were conducted to capture a wide range of vehicle capabilities, operation types, and mission profiles. All acoustic and supporting data were compiled into a database and documented for use in future model validation efforts. Section 4 provides an overview of the measurement campaign, instrumentation, measured launch and landing events, and resulting data products. Together, the research activities described herein fulfill the project objectives and resulted in a dataset of propulsion noise and sonic boom measurements, which can be used to enhance modeling accuracy and validate community noise modeling tools.
