April 26, 2011: For over half a century, the U.S. Department of Defense has been seeking a better night vision system for their pilots, particularly those flying helicopters and low-flying fixed wing aircraft. Decade by decade, the devices have gotten better, but they all had some limitations which, in turn, restricted what pilots could do while flying at night. Now a U.S. firm is demonstrating their HRNVS (High Resolution Night Vision System), which will eliminate the "looking through a straw" problem and provide a much enhanced image. This is one step closer to the perfect night vision system. It's been a long journey.
It was six years ago that the U.S. Air Force has received the first of a new generation of night vision goggles. The ANVG (Advanced Night Vision Goggles) had a 95 degree field of view, compared to 40 degrees for the old ones. The 40 degree field of view was described as looking through a straw and required the user to look around a lot. This got old real fast, caused fatigue, and was responsible for some accidents. The first ANVGs were given to the crew of AC-130 gunships and the MC-130 transports used by SOCOM (Special Operations Command). Both of these aircraft frequently operate at night. A-10 pilots received them next, along with crews on SOCOM helicopters. The initial order was for about 400. The ANVGs cost about $10,000 each and run for twenty hours on two AA batteries.
Five years ago, another improvement was introduced. This worked by projecting what night vision devices (attached to the pilots helmet) saw, right onto the head up display items already being projected onto the helmet visor used by pilots. But when U.S. Marine pilots began using their Top Owl helmet visors in this way, some of them encountered hyperstereopsis (an exaggerated depth perception view). This was not safe for pilots flying close to the ground, so marines went back to using the older night vision goggles. These, despite the "looking through straws" problem, at least avoided any depth perception problems. The Top Owl manufacturer (Thales) developed training methods to overcome the effects of hyperstereopsis when flying under 60 meters altitude, and the marines eventually resumed using Top Owl.
If HRNVS survives testing and initial use by combat pilots, this will represent another major step forward in night vision gear for pilots
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