- Aug 14, 2009
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"Telephonics Developing Radar To Fight Brownout Threat"
May. 5, 2014 - 07:52PM
by MARCUS WEISGERBER
May. 5, 2014 - 07:52PM
by MARCUS WEISGERBER
FARMINGDALE, N.Y. — Landing helicopters in dusty environments or bad weather have long plagued the US military.
Brownout conditions make it impossible for pilots to see the ground and objects around them have caused dozens of troops’ deaths throughout Iraq and Afghanistan.
The Army wants to end those types of risky landings, plus give helicopter pilots the ability to see through bad weather and see hazardous objects, such as wires and towers.
Telephonics, an aerospace and defense firm that specializes in maritime surveillance radars, believes it has developed the solution. The company has self-funded a project called VisionEdge — a system that company officials say is best suited to address brownouts. Telephonics plans to unveil the system this week at the Army Aviation Association of America conference in Nashville, Tennessee.
Company engineers are building several prototype radars, which are at different levels of development.
“What differentiates us from others is our antenna and architecture approach,” said Tim Stow, senior director for airborne warning and control system and flight safety programs.
The radar antenna, which uses a tile architecture, is fairly small, just 25 inches long, 7 inches high and 7 inches deep. Unlike spinning radars, the VisionEdge system provides information in real-time, Stow said at the company’s Long Island, New York-based headquarters.
“Our solution is very compact,” he said. “No moving parts and it can be easily adapted to a variety of unique platforms.”
What also makes the Telephonics offering unique is that it uses a low-frequency radar.
Typically, a higher frequency radar delivers a higher quality image. But a lower frequency system allows the radar to see better through bad weather.
Company engineers needed to strike a balance and settled on a 35 gigahertz frequency radar, Stow said.
“We feel very good about the frequency that we’ve chosen [and] that gives us adequate image resolution,” he said. “To an operator, they have a good picture of what they’re seeing, but [are] able to penetrate through the weather [and] the aircraft-induced environments of dust and whiteout.”
While a higher frequency, 94 gigahertz radar of the same power can penetrate four millimeters of rain per hour out to about 1 kilometer, at 35 gigahertz, the radar could see though the same rate of rain to six kilometers, said Joseph Battaglia, Telephonics president and CEO.
The US Army has already purchased a number of Sierra Nevada-built helicopter autonomous landing systems. The 3D image-rendering radar uses a 94 gigahertz frequency, according to a company fact sheet.
The Telephonics VisionEdge system uses a digital beam forming radar, which doesn’t move, like the spinning radars on ships. A computer attached to the system processes the radar beams, which Stow likened to lining up strips of wallpaper.
“It sends out a lot of energy,” he said. “It receives back a bunch of energy on these fixed beams and then what you have to do though is ... interpolate, basically fill in the gaps between those beams and correlate them so it provides a clean image.”
The ultimate goal is to create a bubble around the helicopter that would allow pilots to see wires, cables, towers and other obstacles, Stow said.
With an added capability, the system can also offer surround sound-like audio cues, which alert the pilot to obstacles.
This means that if an obstacle is off to the right of the aircraft, the pilot will hear the alert from the right side.
Telephonics has partnered with a business aviation manufacturer for development and is looking to conduct flight testing with that company to validate the Vision-Edge concept and architecture, Stow said.
The system has both commercial and military applications. Commercially, the technology could help pilots land at airports in bad weather. The only difference is the military system would show elevation.
On a commercial aircraft, the low-frequency radar would allow a pilot to see the runway in bad weather from a much greater distance, Battaglia said.
When approaching a runway, a pilot must see visual cues on the ground. If the pilot cannot see these objects, such as runway lighting, at an altitude of 200 feet, he or she must abort the landing.
The Federal Aviation Administration wants to use radar to complement existing infrared systems, thus allowing an aircraft to descend below those 200-foot landing minimums, Stow said.
The radar information would be overlaid on a heads-up display.
“This is just another piece of information that reassures the pilot that he’s good to land when he can’t see out the window,” Stow said.
The Army system will perform at a 15-hertz refresh rate allowing the system to display a smooth video image, enabling the pilot to see moving targets, towers and cables.
“We’re leveraging our existing architecture that we initially targeted in the commercial space and we’re applying it to the Army space,” Stow said.
But exactly when the Army will launch a competition for this technology is not clear.
“The Brown Out Rotorcraft Enhancement System (BORES) is currently in the Analysis of Alternatives phase,” Randy Tisor, an Army spokesman, said in an email. “In the September 2014 timeframe, when the AoA is complete, the results of the AoA will be briefed to senior leadership to determine the way ahead for this Degraded Visual Environment capability.”
The fear is that Defense Department research-and-development budget cuts will delay this type of program even further, Battaglia said.
Other companies, such as Sierra Nevada, Rockwell Collins and Teledyne Brown, are all expected to compete for the Army program.