Hover testing a demonstrated and cost-effective risk reduction tool

Kinetic Vehicle (KV) development programs employ a variety of system test techniques to collectively assure vehicle compliance with performance requirements. Before space flight, many programs have included hardware-in-the-loop (HWIL) and hover testing as key system tests. This approach has been shown to efficiently address mission parameters and real world system hardware performance. Hover testing, in particular, has consistently identified unforeseen problems in KV site operations and in flight. Site problems identified and corrected include KV hardware and software design and checkout and test procedures. Hover flight data has identified component and system degradations due to design and propulsion system interaction. In most cases, substantial cost and schedule savings were realized given the alternative of uncovering the same problems at USAKA or WSMR. This paper identifies the merits of hover testing and substantiates the benefits relative to other ground test approaches. Hover test data, its uses, advantages, and limitations in KV development programs are shown. A survey of the hover tests conducted to date is provided, identifying problems uncovered and program impact. In summary, the combined experience of KV contractors has shown the HWIL/hover approach to be highly cost and schedule effective.