US Troops' Gun Sights Can Be Off by a Foot
Thermal drift has been known about for months
By Luke Roney,  Newser Staff
Posted Apr 4, 2016 5:03 AM CDT
A US service member holds a rifle equipped with an EOTech HWS.   (Twitter, US Navy Seals)

(Newser) – EOTech, a firm that has supplied gun sights to the US military, admits that its Holographic Weapon Sight suffers from a defect known as thermal drift. And in November, the company's parent L-3 Communications Corp. agreed to pay $25.6 million to settle a lawsuit brought by the federal government, Bloomberg reported, which claimed EOTech knowingly sold $24 million worth of bad sights to the Defense Department. Months later, though, US Special Operations forces are still using the HWS, which "potentially endangers the lives of service members in combat," per a Washington Post investigation. Thermal drift (the most serious of the several defects with the sight) can cause a shot to be off target by six to 12 inches—"one of the worst types of failures," per an unnamed employee quoted in the lawsuit, "since most users won't notice the problem until their life is on the line."

Problems with the HWS first emerged in 2007, when the Norwegian military noticed that the holographic crosshairs would distort in cold weather. But EOTech didn't tell the Pentagon, even as it continued supplying sights. After that, it was discovered that faulty seals caused the sights to fog up in humid weather. Again, EOTech kept quiet. Finally, the FBI, while conducting ballistic tests, discovered the thermal drift, which occurs in both hot and cold temperatures. A Pentagon rep confirmed that some troops still use the sights, adding that military officials "have an unshakable commitment to the safety" of US armed forces. Another military rep tells the Post the sights are only used in instances that "the limitations of the equipment" don't put troops at risk. Denver police, however, abandoned the sights soon after the November settlement.