Without much fanfare, the U.S. Global Hawk UAV is taking over from manned aircraft, and space satellites. In the past year, Global Hawk was successfully tested a signals intelligence payload, as part of the Airborne SIGINT (Signals Intelligence) Payload (ASIP) program. The high flying Global Hawk can thus do the work of low flying (and much more expensive) SIGINT space satellites. The U.S. Navy also conducted successful tests using Global Hawk for maritime reconnaissance. The air force is also retiring its U-2 reconnaissance aircraft, and replacing them with Global Hawks. The air force and the navy are building at least 50 Global Hawks, and probably more. That's because other nations are developing long range UAVs. Meanwhile, India and Israel are using medium range UAVs (similar to the Predator) for maritime reconnaissance. All of this activity doesn't generally make the news, but it does confirm that UAVs are not just another techno-fad, but are pulling their weight, and replacing manned aircraft, and space satellites as well.