Photonics Spectra - March 2009

der-fired missiles to military and commercial aircraft through the development of onboard IR countermeasure systems. It is developing laser-based directional IR countermeasure systems, which are expected to significantly improve an aircraft’s chances against heat-seeking missiles in comparison with the alternative nondirectional IR countermeasure system technology.

In 2004, the US Department of Homeland Security (DHS) launched its C-MANPADS initiative, under which defense industry contractors are developing and testing existing military defense countermeasure systems for use on commercial airlines. BAE Systems’ JetEye IR missile defense system, for example, completed its first flight on a scheduled American Airlines aircraft in 2008, beginning the final phase of the DHS program to test the suitability of the equipment for commercial aircraft.

Northrop Grumman Corp.’s Guardian
system, which is attached to the belly of a

plane, also has undergone initial testing phases and is being tested in commercial cargo flights. Both systems use an IR sensor to detect missile launches and a laser burst to redirect the attacking guidance system.

At the component level

A typical shoulder-fired missile tracks the target airplane by locking onto the signature of the heat given off by the airplane. Alternate IR countermeasure technologies provide for the deployment of chaff and flares by the target to confuse the guidance system of the missile. Although these systems have been moderately successful, the MANPADS can reacquire the target and hit the airplane.

A major innovation in providing improved protection, directed IR countermeasure technology moves away from the chaff-and-flares approach. The new technology involves an IR laser mounted on a target airplane. The laser activates when a MANPADS firing is detected and con-

fuses the eye and brains of the incoming missile. Various types of lasers in the 4- to 5-μm range, such as optical parametric oscillators and optically pumped semiconductors, have been used, with varying degrees of success.

Pranalytica Inc. of Santa Monica, Calif., recently introduced a turnkey 2-W fully packaged, CW room-temperature quantum cascade laser emitting at 4. 6 μm for incorporation into IR countermeasure systems. Four tier-one aerospace/defense contractors have purchased the company’s 1-W versions since 2008, according to C. Kumar N. Patel, president and CEO.

Because multiple lasers can be incorporated into the directional IR countermeasure systems, the 2-W components provide simpler, smaller and more cost-effective technology for the task, while providing a greater range of protected area. The components offer high reliability and are energy-efficient.

Caren B. Les caren.les@laurin.com

Night-vision goggles no longer just for military

TEMPE, Ariz. – Pilots flying aircraft at night and during low-light conditions know how difficult it can be to perform flight operations when visibility is limited. Not seeing clearly can seriously affect what could already be a dangerous task. Medical responders and search-and-rescue units, law enforcement teams, and others

who must fly in the dark near offshore oil rigs, power lines or high rises, for example, are especially at risk.

Now, in an attempt to alleviate the dangers, the Federal Aviation Administration has approved certified military-use-only night-vision aviator goggles (NVAG- 6) for civilian pilots.

“Night vision is a phenomenal asset to be using,” said Lee A. Stephens, senior technical applications manager at Nivisys Industries LLC. “They help any night operation in the form of greater visibility and situational awareness.”

The goggles are made by Nivisys, a manufacturer of thermal and night-vision equipment specializing in Aviator Night Vision Imaging Systems (ANVIS), which feature high-resolution, lightweight, easy-to-operate binoculars designed to fit helmets worn by helicopter pilots and fixed-wing aircraft aviators.

According to Stephens, the equipment must go through environmental performance requirements to gain Technical Standard Order (TSO) certification, a minimum performance standard issued by the FAA for civil aircraft equipment. “The NVAG- 6 meets TSO-C164 approval,” he said. “We’re the only night-vision goggle manufacturer to receive this certification.” A C164 order is specific to head-mounted, binocular, night-vision goggles.

Shown is a pilot looking through the NVAG- 6 goggles. Inside an aircraft, the pilot must shift his eyes below the goggles to see the instrument panel because the binoculars allow visibility only in the near-infrared spectrum. Courtesy of Nivisys Industries.