Rocket Landing on Irregular Surfaces

TECH FOCUS AREAS: Autonomy; General Warfighting Requirements (GWR) TECHNOLOGY AREAS: Space Platform; Air Platform OBJECTIVE: Both Tactically Responsive Space Access as well as Rocket Cargo have the need to lift-off from and/or land on a non-improved, irregular surface. This could be anything from a parking lot to an irregular farm field. However, little work has been conducted in landing a rocket on flat, improved surfaces, let alone these types of surfaces. This topic seeks to develop strategies that can be used to enable landing on these surfaces as well as mitigations that can be potentially implemented to enable this capability. Mitigations can either be lightweight structures that can be placed on the landing surface or structures, strategies placed on the rocket, nozzle technologies that address the plume impaction, smart landing structures, and landing software. DESCRIPTION: Although vertically landing a rocket on an improved, flat surface has been achieved by multiple launch vehicle companies (Masten Space, SpaceX, Blue Origin), landing a rocket vehicle on an irregular, unimproved surface has a number of challenges including, but not limited to the rocket sinking in the surface, the plume kicking up dust and creating an observable event, and the uneven footing causing the rocket to fall over. The terrain that the rocket vehicle may land in is also unpredictable and not known a priori. Any solution needs to be broad enough to handle multiple potential landing challenges and to be able to adjust to the situation seen at landing. This topic seeks to address these and other challenges at sub-scale levels in phase I and phase II and transition those technologies to a full-scale vehicle in Phase III. The intent of this topic is to accelerate the development of technologies to vertically land a rocket on an irregular, un-improved surface. It is recognized that a number of different technologies are possible to achieve the overall objective. This can include (but is not limited to) sensor technology on the lander, nozzle technology to mitigate plume impingement, venting of gases and liquids from the vehicle as it is landing, as well as mitigating ground structures that can easily and quickly be applied to a surface. It should be noted that it is necessary to balance precision in the landing location, speed of access to vehicle after landing with terrain avoidance, and minimizing potential observability issues such as the creation of dust cloud which can cause damage to nearby structures as well as allow for viewing of the landing site from a distance. Approaches to maturation to full-scale should include sufficient engineering analyses to provide confidence of feasibility and pathway to feasibility at full scale. Supporting analyses should also consider limitations in the physical architecture of both the sub-scale and the potential full-scale systems. PHASE I: Perform analysis and/or demonstrations of vertically landing a rocket on an irregular, non-improved surface in order to identify critical technical challenges and explore feasibility of the proposed concept. PHASE II: Perform sub-scale testing to demonstrate feasibility of vertically landing a sub-scale rocket on an irregular, non-improved surface. Achieve TRL 6 for a sub-scale test article. PHASE III DUAL USE APPLICATIONS: Transition of Phase II technology to a full-scale demonstration program. This effort will include all necessary activities for flight qualification as well as support for a full-scale test landing on an irregular, non-improved surface. NOTE: The technology within this topic is restricted under the International Traffic in Arms Regulation (ITAR), 22 CFR Parts 120-130, which controls the export and import of defense-related material and services, including export of sensitive technical data, or the Export Administration Regulation (EAR), 15 CFR Parts 730-774, which controls dual use items. Offerors must disclose any proposed use of foreign nationals (FNs), their country(ies) of origin, the type of visa or work permit possessed, and the proposed tasks intended for accomplishment by the FN(s) in accordance with section 5.4.c.(8) of the Announcement and within the AF Component-specific instructions. Offerors are advised foreign nationals proposed to perform on this topic may be restricted due to the technical data under US Export Control Laws. Please direct questions to the Air Force SBIR/STTR Contracting Officer, Ms. Kris Croake, kristina.croake@us.af.mil. REFERENCES: 1. Sutton, G.P., History of Liquid Rocket Engines, American Institute of Aeronautics and Astronautics, Reston, Virginia, 2006. 2. G.P. Sutton & O. Biblarz, Rocket Propulsion Elements, 7th Ed., John Wiley & Sons, Inc., New York, 2001, ISBN 0-471-32642-9. 3. D.K. Huzel & D.H. Huang, Modern Engineering for Design of Liquid-Propellant Rocket Engines, Vol 147, Progress in Astronautics and Aeronautics, Published by AIAA, Washington DC., 1992, ISBN 1-56347-013-6. 4. Yang, V et. al, Liquid Rocket Thrust Chambers: Aspects of Modeling, Analysis, and Design, Vol 200, Progress in Astronautics and Aeronautics, Published by AIAA, Washington DC, 2004, ISBN 1-56347-223-6, pp 403-436. 5. Oberkampf, W.L. & Trucano, T.G. Verification and Validation in Computational Fluid Dynamics , Vol. 38, Progress in Aerospace Sciences, 2002. Pp. 209-272.