HIFiRE-1: Payload Design, Manufacture, Ground Test, and Lessons Learned

Abstract

HIFiRE (Hypersonic International Flight Research Experimentation) is a joint flight test program supported by the US Air Force Research Laboratory (AFRL) and the Australian Defence Science and Technology Organisation (DSTO). One of the main program goals is to gather basic research data on aspects of hypers onic flight not easily accessible to ground testing. Flight one focuses primarily on integration of instrumentation on the test vehicle, with application to boundary layer transition and shock interaction experiments. The HIFiRE 1 payload consists of a blunted 7° half angle cone and a cylinder/33° flare configuration. The payload will be boosted to Mach 8 utilizing a two stage Terrier-Orion sounding rocket. The payload was designed and manufactured to achieve the desired boundary layer transition and shock boundary layer interaction properties and collect the required data. Extensive analysis and ground testing was conducted to ensure the payload will survive the expected flight environment. The HIFiRE 1 launch campaign is scheduled for March 2010. A number of valuable lessons learned during the development of HIFiRE 1 are included in this paper. I. Introduction HIFiRE is a cooperative flight test program between the United States and Australia. The goal of this program is to advance technologies associated with hypersonic flight. Special emphas is is placed on exploring phenomena not readily accessible to ground tests. Fli ght one will focus on instrumentation an d telemetry systems to be used for flights occurring later in the program. The primary objec tive of HIFiRE 1 is to determine the feasibility of applying high-bandwidth instrumentation to aero-thermal flight measurements for short duration hypersonic flights at Mach numbers up to eight. The experiment will determine the suitability and survivability of multiple instrumentation types in this environment. The experiments will be incorporated into the nose cone of a Terrier-Orion launch vehicle 1 . This paper will refer to the nose cone as the “payload.” The measurement of three aero-thermal phenomena will serve to assess the performance of the instrumentation. The corresponding sub-experiments are, in order of priori ty, boundary layer transition (BLT), turbulent separated shock boundary layer interaction (SBLI), and optical measurement of mass capture (OMC). This paper describes the design, manufacture, integration and ground testing of the payload. It also includes valuable lessons that were learned during this process. The scientific motivations for the primary and secondary experiments on HIFiRE 1 have been discussed in a number of published papers 2,3,4,5,6,7,8,9 and will not be repeated here. Design parameters critical to the BLT experiment have been derived from past correlations, computational analyses and ground testing. The most critical paramete rs affecting the BLT experiment are surface roughness and step/gap sizes at and between payload sections. The most restrictive values were 0.08mm for an allowable discrete roughness and 0.001mm root mean square (rms) roughness at the nosetip (relaxing to 0.008mm rms aft of the nosetip). More recent results 3,10 indicated that larger values would have been acceptable, however the more restrictive roughness limits were employed for the payload design to provide a generous factor of safety for the experiment. A discrete roughness trip was installed on one side of the payload with the aim of extracting