Phase Sensitive Innovations’ novel imaging technology sees through the fog
Getting shot down isn’t the only threat faced by helicopter pilots flying in combat zones. In certain environments, the elements can be as dangerous as the enemy. In Iraq and Afghanistan, for instance, the thick dust created when a helicopter hovers close to the ground can cause even experienced pilots to crash. Degraded visuals sometimes lead to controlled flight into terrain (CFIT), an accident scenario in which an aircraft, under pilot control, is unintentionally flown into an obstacle. In a CFIT situation, the pilot and crew are unaware of the imminent disaster until it is too late. During recent wartime operations in desert theaters, the potential for CFIT necessitated that countless missions be modified. Operations that may have required the delivery of 100 marines into a contested area had to be adjusted because the helicopter could only handle 30 to 50 personnel in one transport. Due to dust clouds and the resulting lack of visibility, called “brownout” conditions, the pilot would have to wait for the air to clear, or do a second personnel drop in another area. Both options put soldiers at considerable risk. In the late 1990s and early 2000s, a small group of researchers at the University of Delaware tried to solve the problem. Fortuitously, they were already working on a Defense Advanced Research Projects Agency (DARPA) funded millimeter-wave imaging project. Their goal was to identify frequencies of interest to the military. Situated between the microwave and infrared section of the electromagnetic spectrum, millimeter waves are electromagnetic radiation with wavelengths in the range of 10mm to 1mm (with corresponding frequencies of 30 to 300GHz). However, without electronic components that could generate or receive millimeter waves, this range of the spectrum was largely unused and represented a treasure chest of new opportunity.