The F-35 Joint Strike Fighter is a 5th Generation fighter, combining advanced stealth with fighter speed and agility, fully fused sensor information, network-enabled operations and advanced sustainment. The F-35 will replace the A-10 and F-16 for the U.S. Air Force. This advanced fighter is equipped for multi-mission capability for emerging global threats.
Air Force Research Laboratory (AFRL) has contributed significantly to the development of highly specialized features and enhancements that assure the F-35’s superiority for years to come. The following are some of the highlights of AFRL’s involvement:
Replacing most aircraft hydraulic and mechanical systems with lighter weight and more reliable electrical systems. These electrical systems are also easier to maintain and less costly.
Replacing traditional externally mounted antennas for communications and sensors with antenna systems that use the skin of the aircraft reducing drag and vulnerability to radar detection.
Increasing the thrust of the jet turbine engine by almost 100% through a two-decades-long Integrated High Performance Turbine Engine Program allowed the use of only one engine instead of two on the previous generation F-22.
Adding full Helmet Mounted Display capabilities to the F-35 gives the pilot full heads-up display information no matter what direction the pilot is facing. This makes the fighter more lethal and survivable than its predecessors.
Remotely Piloted Aircraft pilots will fly like they’re airborne thanks to a system that provides an enhanced ability to dynamically maneuver the plane. The AFRL is developing the system, logically named the Dynamic Maneuvering operator interface and informally known as "DynaMan."
Many Air Force (AF) missions require quick responses from pilots and maximum performance from aircraft. In the case of traditionally piloted aircraft, pilots move the stick and throttle and receive immediate feedback from the aircraft and environment. For Remotely Piloted Aircraft, the control loop is not as direct. During operations beyond the line of sight, there is currently a delay of about 1.8 seconds between the pilot’s control input and system feedback — the operator does not see the result of control input for nearly 2.0 seconds.
Two of the most important pieces of information used by pilots in flight are the state of the aircraft (a plane’s orientation and energy, such as altitude, airspeed and course), and the frame of reference (the horizon or direction of motion). This 1.8 sec lag inhibits a pilot’s ability to perform precise maneuvers at a moment’s notice.
With DynaMan, the pilot enters the desired control inputs using the familiar stick and throttle. The control station sends these inputs to the aircraft and to the simulations, and both destinations execute the control inputs upon receipt. The simulation displays the instantaneous response of the simulated aircraft and the virtual world, allowing for smoother control of the vehicle. The aircraft response is received 2.0 seconds later and is compared to the simulation response. Any differences are applied to the simulation, bringing it in line with what actually happened.
In manned aircraft, the real world acts as the frame of reference for pilots. The RPA frame of reference is currently displayed as a narrow field of view of the real world - like looking through a straw. Addressing this impairment, DynaMan incorporates offboard datalink information that tells the pilot about objects surrounding the aircraft in airspace, such as clouds and other aircraft, providing pilots with a 360° view. The datalink information is currently simulated, but there are plans to begin feeding live datalink information into the system for evaluation.
Image: Bob Shaw, a retired AF Reserve pilot and subject matter expert for the 711th Human Performance Wing’s Human Effectiveness Directorate, Warfighter Interface Division, Supervisory Control Interfaces Branch, evaluates the symbology and flight dynamic algorithms used in a DynaMan synthetic world.
AFRL-supported physicists at the University of California, Berkeley, in collaboration with researchers from the Max Planck Institute of Quantum Optics and the US Department of Energy’s Lawrence Berkeley National Laboratory, became the first researchers to observe the motion of an atom’s valence in real time by investigating the ejection of an electron from an atom by an intense laser pulse.
In the experiments, an electron in a krypton atom is removed by a laser pulse that lasts less than four femtoseconds (one femtosecond is one millionth of one billionth of a second). This process leaves behind an atom with a pulsating positively charged hole in the valence shell, which originates from electronic wave functions of the atom.
The scientists used an extreme ultraviolet light pulse, the duration of which was 150 attoseconds (1 attosecond is one billionth of one billionth of a second), to capture and photograph the movement of valence electrons for the first time.
This research is expected to enable the scientists to better control processes and materials that will improve high-speed electronics and carbon-free energy sources that will benefit both the Air Force and consumers.
Image: This is the classical representation of electrons in a krypton atom.
Air Force (AF) personnel are losing weight and gaining comfort thanks to new non-ceramic ballistic armor developed by the AFRL. Working with Universal Technology Corporation and Armacel Armor Corporation, AFRL scientists developed armor that demonstrates protection against ammunition from shoulder-fired weapon threats while weighing 32% less than current armor systems.
The new body armor technology also increases the survivability of warfighters in armed conflicts, while its lighter weight translates into increased mobility and a decrease in thermal load. Based on stopping power and back face deformation against standard small arms fire, the new armor offers significantly improved ballistic performance and ergonomic benefits.
The current standard for body armor, known as Enhanced Small Arms Protective Inserts (ESAPIs), combines a ceramic and composite material torso plate with a woven aramid multi-ply carrier system. While the ESAPI system is effective against rifle threats, the material is fragile, the ceramic strike face is breakable, can fracture with rough handling, and the carrier system is obtrusive and heavy.
The new ballistic armor technology uses polymer and composite materials technologies; advanced manufacturing processes are also being developed to provide the warfighter with affordable, survivable body armor. One advantage of the new system is that it can be molded into more complex shapes, offering designers more options.
The armor was tested during a Tech Warrior Pre-Deployment exercise in a simulated operational environment. It is currently deployed to military personnel at Bagram Air Base, Afghanistan, where scientists are conducting non-combat ergonomic fit testing and eliciting feedback from deployed AF personnel.
Image: Lightweight, ergonomic, non-ceramic ballistic armor offers more comfort and mobility for deployed warfighters.
Supercomputers consume super amounts of energy, and there is an ongoing technological solution to reduce that consumption. Funded in part by Air Force Office of Scientific Research, a Stanford University team unveiled a tiny, highly efficient semiconductor laser that could herald a new era in low-energy data interconnects that communicate with light as well as electrons.
The effort concerns a type of data transmitter known as a photonic-crystal laser that besides being fast and small, also operates at very low energy levels. The team has produced a nanoscale optical data transmitter – a laser – that uses 1,000 times less energy and is 10 times faster than the very best laser technologies in commercial use today. The laser is based on a multi-layered wafer of gallium arsenide, embedded with three thin layers of a second crystal, indium arsenide, with quantum dots within the wafer. When compiled, the nanophotonic layered stack is only 220 nm thick. At the heart of the wafer, photons are concentrated and amplified into a tiny ball of laser light which can be modulated up to 100 billion times per second (10 times the rate of the current top-rated data transmitters) with the light becoming binary data: light on for one; light off for zero. Hundreds of these nanophotonic transmitters could be arranged on a single layer, and many layers could then be stacked into a single chip.
While this new technology currently operates at relatively cold temperatures (about -190°F), the team is working toward perfecting operation at room temperature while maintaining energy efficiency at about 1,000 times less than today’s commercial technologies.
Image: Researchers have developed a nanoscale, highly efficient optical data transmitter or semiconductor laser, the key to which is a multi-layered nanophotonic layered wafer, the holes of which are almost perfectly round with smooth interior walls and act like a hall of mirrors to reflect photons back toward the center of the laser.
A team from the AFRL is investigating a new series of stimuli-responsive nanocomposites, which change their mechanical properties when exposed to electric fields and electromagnetic radiation. The mechanical morphing of the new materials is the result of synergistic interactions between the nanofiller and the polymer matrix. The team established a coherent material-performance relationship for electric-field actuation, enabling evaluation and optimization for various structural morphing applications.
This research was the first to clarify the role of carbon nanotubes in electrostrictive polymer nanocomposites (PNCs), thereby focusing subsequent development in the community. It provides a rational basis for the design of PNC-based devices and establishes limits on conductive nanoparticle-filled PNCs for mechanical actuators. It will enable an assessment of the manufacturability of the materials and their use in various Air Force applications.
Lightweight, mechanically adaptive materials are desirable for a broad array of technologies, from medical stents to deployable telescopes and morphing air vehicles. They are crucial for morphing systems including Remotely Piloted Aircraft, low-profile munitions, satellites, and automatic target recognition sensor arrays. However, inadequate temperature stability, cyclability and controls limit their use in some applications. Researchers recognize polymer nanocomposites (PNCs) as a solution to this, but actuation and mechanical adaptivity were not well understood. A realistic assessment of their impact, durability prediction, and performance optimization was needed.
Researchers assembled a multi-disciplinary team to investigate the mechanism of electric field actuation in PNCs. They developed predictive mechanical models which showed that PNC electrothermal actuation does not depend on the composition of the nanofiller, but only on the resultant macroscopic conductivity of the PNC. This establishes the rationale for nanofiller selection, amount of nanofiller addition, and processing methods to control morphology.
These findings will help focus efforts on next-generation adaptive materials and provide a rational basis for design of PNC-based devices.
Image: An artist’s rendering of the 21st Century Aerospace Vehicle, nicknamed the Morphing Airplane, shows advanced concepts National Aeronautics and Space Administration envisions for an aircraft of the future.