The American GBU-44 Viper Strike smart bomb has been modified to hit fast moving vehicles and was recently successful in eight out of eight tests. The manufacturer hopes that this new capability will lead to more sales. There have not been many sales so far. Viper Strike began development during the 1980s, but never entered service because the Cold War ended along with the need for many weapons designed to deal with thousands of Russian tanks advancing into Western Europe. A decade ago Viper Strike showed up, as a compact, lightweight precision glide bomb. Still not a lot of sales.
Five years ago a U.S. Army UAV first used a Viper Strike in combat. Three years ago a GPS guided version of the Viper Strike was introduced. SOCOM spent over $20 million on making Viper Strike work on their AC-130 gunships, in place of the 105mm cannon. But this didn’t work out, even though the use of Viper Strike would allow the AC-130 to fly higher (than required for the 105mm weapon to be used) and be safer from ground fire. Technically, Viper Strike is still "under consideration" for the AC-130.
Meanwhile, because the MQ-5A is the only aircraft using the Viper Strike, there is not enough demand to put the Viper Strike into mass production. Worse, the MQ-5A Hunter will soon be replaced by a larger Warrior UAV that can carry heavier Hellfire missiles. But the GPS version of Viper Strike is supposed to make this weapon even more useful, and popular, and maybe that will lead to wider adoption.
Viper Strike is a 92 cm (36 inch) long unpowered glider. The 130mm diameter (with the wings folded) weapon weighs 20 kg (44 pounds). Because the Viper Strike can come straight down, it is better suited for urban warfare. Its warhead weighs only 1.8 kg (four pounds), and less than half of that is explosives. This means less damage to nearby civilians but still powerful and accurate enough to destroy its target. A laser designator makes the Viper Strike accurate enough to hit an automobile or a foxhole. However, people on the ground tend to prefer the faster (rocket propelled), larger (48 kg, with a 9 kg warhead) Hellfire missile. And then there are even lighter competitors coming along, like the 11.4 kg, 70mm laser guided rocket with a 2.1 kg warhead.
The first test of Viper Strike, launched from a UAV, took place eight years ago. The delays, in getting this weapon in the hands of the troops, were caused largely by disagreements over technical and organizational issues. Not an uncommon event, although in wartime it's often possible to cut through the crap. Part of that dispute is with the U.S. Air Force. For over half a century the army and air force have abided by the "Treaty of Key West," an agreement president Eisenhower forced them to hammer out. The terms gave the air force a monopoly on fixed wing warplanes and allows the army to only operate small, two engine, fixed wing transports. However, the army can have all the helicopters it can get. UAVs were not covered in the Key West agreement, although UAVs existed in the 1950s. But armed UAVs were still only a distant possibility back then. Now the air force wants to extend its fixed wing monopoly to include armed UAVs. The army did not agree, and the Pentagon agreed to revise the Key West treaty and allow the army to continue rebuilding the new Army Air Force with larger (20 kg) UAVs.