Business Jets Bounce Back

The business jet market has a resilience all its own. While defense spending has sharply declined, the commercial sector is over-flowing with multi-thousand order backlogs. But if business jet orders can tail off dramatically and then bounce back so quickly, what accounts for this collective long-term immunity to volatile market demands?

Posted in: Articles, Aerospace, Aviation, Defense, Product development, Business and general aviation aircraft

Enhancing Mission Readiness with Rugged Portable Instruments

To support warfighters in the field, engineers and technicians install, maintain, troubleshoot, and repair a wide range of mission-critical radar and communication systems. These tasks typically require measurements of cables, antennas, components, signals, and more. Often, this work must be done in non-ideal conditions such as rain or shine, hot or cold, aboard a ship, in an aircraft, or in a vehicle.

Posted in: Articles, Aerospace, Defense, Antennas, RF & Microwave Electronics, Antennas, Radar, Telecommunications systems, Military aircraft, Military vehicles and equipment

RF Photonics for Avionics Signal Processing

The maturity of RF photonic components has reached the point where fiber optic links are being system-tested to replace traditional copper coax links on avionic platforms. Many demonstrations of RF photonic links have been made with traditional and non-traditional modulation formats to improve the RF performance of the link. While the advantages of RF photonic links in regard to size and weight are important, the large instantaneous bandwidth of the fiber optic links is a key driver for the use of this technology in the airframe.

Posted in: Articles, Aerospace, Defense, Fiber Optics, RF & Microwave Electronics, Avionics, Optics

Continuous Sputter Deposition Coating of Long Monofilaments

A thin, uniform coating on long segments of monofilament could drastically improve the functionality of many complex fibers. A length of fishing line, microtubing, or polylactic acid (PLA) coated with copper could be left to cure within an epoxy, and upon removal of the monofilament, a narrow channel with a thin outer wall of copper would remain. That channel would be open for fluid flow, and also have a conductive shell. The “vascularized” material could be used for thermal management or self-healing composites.

Posted in: Briefs, Aerospace, Defense, Coatings & Adhesives, Materials, Thermal management, Adhesives and sealants, Coatings Colorants and Finishes, Copper, Fibers, Hoses

Hydrolytic Stability of Polyurethane-Coated Fabrics Used for Collapsible Fuel Storage Containers

Collapsible fabric fuel tanks have provided critical tactical bulk petroleum storage for military operations for over 50 years. Beginning in the 1940s with the 900 to 3,000-gallon pillow tanks, collapsible fabric tanks have evolved into the primary tactical fuel storage vessels now used by all of the military services.

Posted in: Briefs, Aerospace, Defense, Coatings & Adhesives, Materials, Containers, Storage, Coatings Colorants and Finishes, Fabrics, Fuel tanks, Military vehicles and equipment

Materials Design Principles for the Dynamic Fracture of Laminar Composite Structures

Crack bridging (e.g., from stitches or pins) and friction have profound and potentially very useful effects on delamination crack growth, controlling growth rates (damage levels) and the energy absorbed. However, the implications for structural design principles have remained quite obscure. The difficulty is that no simple analogue of crack toughness, which underpins static structural design, exists for dynamic cases with large-scale bridging effects. The external shape of the structure and the loading configuration dictate stress waves, frictional contact zones, and crack tip stress intensity factors in a way that is very difficult to approach, other than by brute case-specific numerical simulation. The problem is compounded by the common occurrence of multiple cracking, a complexity that is rarely entertained in laboratory fracture specimen design. Physically sound material models for the important structural problem of multiple, nonlinear cracking in laminated structures with large-scale bridging due to friction and reinforcement had previously remained undeveloped, in spite of the technological importance of these systems.

Posted in: Briefs, Aerospace, Defense, Electronics & Computers, Information Technology, Materials, Finite element analysis, Composite materials

Development of Hydrophobic Coatings for Water-Repellent Surfaces Using Hybrid Methodology

Coatings that impart hydrophobic properties are of considerable interest. For applications such as aircraft windows, optical components, protective eyewear, and clothing, this type of surface is desired for the material to be soil-repellent and waterresistant. A prime model of a surface with these characteristics can be found in nature – the leaves of the lotus flower have super-hydrophobic properties as a means of self-cleaning.

Posted in: Briefs, Aerospace, Defense, Coatings & Adhesives, Materials, Windows and windshields, Optics, Coatings Colorants and Finishes, Protective equipment

Researchers Develop Multiphysics Model for Electro-Thermal Analysis of UAV

Vives College University and Kulab (KU Leuven University campus Ostend) in Belgium are undertaking an aeronautical research program for the development of a new UAV aimed at performing scientific missions along the Belgian coastline above the North Sea. The main performance requirement of the UAV, dubbed Litus, is to be electrically powered with a range of 160 km and a payload up to 5 kg.

Posted in: Technology Update, Aerospace, Defense, Simulation Software, Simulation and modeling, Electrical systems, Thermal management, Unmanned aerial vehicles

Small, Sensitive Antennas

Researchers create metamaterials by carefully designing and fabricating novel structures to exhibit patterns of electromagnetic properties—specifically, dielectric permittivity and/or magnetic permeability—at the micro-or nano-scale. This special spatial arrangement of elements ensures that the volumetric arrays interact with electromagnetic fields in desirable ways.

Posted in: Technology Update, Aerospace, Defense, Antennas, Antennas

Unmanned Ocean Drone

Liquid Robotics
Sunnyvale, CA

Accurately forecasting weather conditions and currents prior to mission deployment is an invaluable intelligence tool for the warfighter. Being able to accurately predict a Category-5 typhoon or hurricane, instead of a tropical storm, also saves lives, saves property, and saves time in evacuations. The Liquid Robotics' Wave Glider®, a surfboard-sized ocean drone filled with sensors, computers, and communications equipment, can survive a Category-5 typhoon while continuously collecting and transmitting meteorological and oceanographic data. Previously this type of data was unobtainable because it was too risky to send manned ships out in the middle of a hurricane/typhoon; buoys can become severely damaged or come off their moorings in such conditions; and satellites have difficulty seeing through the dense cloud cover.

Posted in: Application Briefs, Aerospace, Communications, Defense, Thermal Management, Data Acquisition, Robotics, Marine vehicles and equipment, Unmanned aerial vehicles