In April, the US Defense Department awarded Boeing Co. a $110 million contract to help develop a 26-ft. unmanned airplane capable of evading radar. Engineers are investigating the use of enabling technologies such as super-resolution radar, electro-optical imaging and laser targeting to secure communications and signal compression. Initially, these jets would fly ahead of manned fighter jets on high-risk missions to wipe out enemy air defenses. The first flight tests are scheduled in 18 months, and production could begin in about five years. The jets are expected to cost about $10 million apiece.