A year ago, the U.S. Army received the first few hundred of the new helmet mounted ENVG (Enhanced Night Vision Goggle). The ENVGs were so successful that the army has ordered 50,000, so that all troops in a combat zone can have them. The ENVG were particularly useful spotting hidden (in the brush) enemy gunmen at night. Troops equipped with ENVG have a 50 percent probability of spotting these hidden hostiles at 300 meters and an 80 percent probability at 150 meters. This made it much more difficult for enemy fighters to ambush American troops at night. Since the enemy rarely has night vision gear, they have to rely on sound and fleeting glimpses of the approaching Americans. That means the U.S. troops have to be less than 50 meters away before the enemy can open fire. The ENVG thus provides a crucial edge at night. This has been great for American morale, not so good for the Taliban.
The new ENVG combines the older light enhancement technology goggles, with a thermal (heat sensing) night sight. This combined sight weighs about one kilogram (two pounds). The older ENVG (thermal only) weighed 864 gr (1.9 pounds), while the AN/PVS-13 light enhancing device weighed 568 gr (1.25 pounds), for a total of nearly a kilogram (2.15 pounds). The new sight is not only lighter, but more compact and easier to use. It provides a total of 15 hours' use (7.5 hours for thermal imaging and the same for light enhancement). In most cases (where there is some star or moon light) the light enhancement sight will do. But where there is no other light (as in a building or cave) the thermal imager works. The thermal imager also works through fog and sand storms.
It was four years ago that field testing of the original ENVG (the AN/PAS13) took place. This device worked with the current AN/PVS-14 night vision goggles (which provide night vision by enhancing available light), but added the capability to use thermal imaging (seeing differences in heat). As more combat moved to Afghanistan, the ENVG became more critical for battlefield success at night.
Until a decade ago, thermal imaging equipment was large and bulky and only available in vehicles (M-1 tanks and M-2 Bradleys). But in the last five years, smaller and lighter thermal imagers have come on to the market. The U.S. Army Special Forces has been using these lightweight thermal imagers to great effect from the very beginning of their development.
Field testing of the combined device began two years ago, and was quickly found to be popular and reliable. The earlier thermal imager was also very popular, but carrying both night sights was not. The army already has nearly 2,000 of in EBVG service. At first, the plan was not to equip all combat troops with the more expensive combined sight. That has changed. Non-combat troops will not give everyone an ENVG, but every unit will have some. The army found the money ($770 million) to buy over 50,000 of the new ENVGs, which cost about $15,000 each. It takes a while to manufacture these devices, and the army will only have about 10,000 of them by 2012.