TECHNOLOGY AREA(S): Weapons

ACQUISITION PROGRAM: PEO IWS 3A, STANDARD Missile Program Office

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 statement of work (SOW) tasks intended for accomplishment by the FN(s) in accordance with section 3.5 of the Announcement. Offerors are advised foreign nationals proposed to perform on this topic may be restricted due to the technical data under US Export Control Laws.

OBJECTIVE: Develop conformal antenna and antenna cover (i.e., radome) materials that provide stable antenna performance in increasingly demanding flight environments.

DESCRIPTION: Evolving weapons technology is driving missiles and other flight vehicles to greater speeds and higher accelerations. The result of increased speed and acceleration is higher temperatures and thermal stresses. For instance, with vehicles traveling over Mach 4, surface temperatures can reach 1,500°C or higher.  Rapid acceleration can result in extreme thermal gradients, which translate to high stresses. These increases require changes in materials to meet or exceed requirements to negate the effects on missile antennas and radomes.

The Navy needs new materials that package missile antennas in conformal configurations that can withstand these demanding new flight environments. These configurations may be with the antenna either directly on the vehicle surface or behind a conformal antenna radome. Flight environments include shock at launch (e.g., 30,000g for gun-launched projectiles), acceleration from zero to over Mach 5 in milliseconds to seconds, altitude of flight from sea level to 200,000 feet, and flight through adverse weather (e.g., rain, sleet). Most applications are limited by size and shape profile constraints (e.g., airframe fitting in its canister).

The primary focus of this SBIR topic is advanced materials, which would enable use of radomes or conformal antennas in more aggressive environments. The material property sets required for these two applications have substantial overlap, which means an advanced material may be useful for both, but optimal for one in particular. The Navy believes that the existing designs for radomes and conformal antennas are adequate, and that materials are the limiting factor in increasingly aggressive environments. There are specific material properties, namely dielectric constant and loss tangent, which need to be low (preferably below 5 and .05 respectively). While proposals describing advanced materials are anticipated, an engineering solution that allows use of existing state-of-the-art materials in extended service will be considered.

Antenna and radome materials must provide for stable performance over the duration of its flight. Thermal shock is particularly difficult and can cause expansion of the outer surface during acceleration, thereby impacting both antenna electrical performance and material structural integrity. In addition, it is anticipated that future antenna applications will require frequency selective surfaces for electrical performance. These conductive patterns add requirements for surface smoothness and outer surface protection. The incorporation of a pattern layer, and any associated coatings, may further complicate the thermal shock performance. Possible applications for the desired technology include tactical missiles, long-range guided projectiles, and hypersonic vehicles.

PHASE I: Develop a concept for conformal antenna and radome materials that meets the parameters in the Description. Demonstrate that the concept can feasibly meet the requirements in the Description. Demonstrate feasibility through analysis, modeling, and experimentation of materials of interest to meet the parameters in the Description. Develop a Phase II plan. The Phase I Option, if exercised, will include the initial design specifications and capabilities description to build a prototype solution in Phase II.

PHASE II: Develop models to produce notional full-scale prototypes that will be delivered at the end of Phase II. Demonstrate that the prototype can function under the required service conditions including thermal and mechanical stresses as stated in the Description. Perform testing that includes high-temperature mechanical tests, thermal shock tests, electrical tests, non-destructive testing, and microstructural examinations to show the prototype will meet Navy performance requirements. It is expected that offerors will propose technology solutions with the highest capability they can imagine, and will test to show such capability.

PHASE III DUAL USE APPLICATIONS: Support the Navy in transitioning the technology for Navy use in future missile development. Support the manufacturing of the components via the technology developed under this topic, and assist in extensive qualification testing defined by the Navy program.

Potential commercial uses for high-speed antenna performance improvements are in the commercial spacecraft and satellite communications industries. The materials appropriate for this topic should have lower thermal expansion and higher erosion resistance than polymeric antenna materials, making them attractive for satellite applications where differential expansion from solar heating and erosion from micrometeorite impact are concerns.

REFERENCES:

1. Kasen, Scott D. “Thermal Management at Hypersonic Leading Edges.” PhD Thesis, University of Virginia, 2013. http://www.virginia.edu/ms/research/wadley/Thesis/skasen.pdf

2. Johnson, Sylvia. "Ultra High Temperature Ceramics: Application, Issues and Prospects.” American Ceramic Society, 2nd Ceramic Leadership Summit, Baltimore, MD, August 3, 2011. http://ceramics.org/wp-content/uploads/2011/08/applicatons-uhtc-johnson.pdf

3. Atherton, Kelsey. “The Navy Wants To Fire Its Ridiculously Strong Railgun From The Ocean.” Popular Science, 8 April 2014.
http://www.popsci.com/article/technology/navy-wants-fire-its-ridiculously-strong-railgun-ocean

4. Walton, J.D. “Radome Engineering Handbook.” Marcel Dekker, Inc., New York, 1970.

KEYWORDS: Missiles; Guided Projectiles; Antenna Radomes; Antennas; Thermal Shock; Missile Erosion; Hypersonic