This all began last year when the U.S. Air Force cancelled all orders for the Block 30 Global Hawk because of reliability issues. This renewed Department of Defense threats to cancel the Global Hawk program entirely. In response Northrop Grumman (the RQ-4 manufacturer) lobbyists made sure that key members of Congress knew where Global Hawk components were being built and how many jobs that added up to. Elected politicians pay attention to that. This move delayed the RQ-4 Block 30 until there was enough political support to convince Congress to order the air force to accept the Block 30 RQ-4s and shut up.
The air force can take some comfort in the fact that Northrop Grumman fixed some of the problems (some of which the manufacturer said don't exist or didn't matter). The Block 30 was supposed to be good to go but the air force was not convinced and decided that Block 30 was just more broken promises. Congress was also tired of all the feuding and being caught between Northrup lobbyists and exasperated air force generals. The lobbyists, as is usually the case, eventually won. But the air force is not required to pay for operating the Global Hawks, thus the disbanding of the Global Hawk unit.
The air force believes it has larger issues to worry about. There is still the political decision to cut the defense budget over the next decade. Another problem the air force sees is that the most likely future conflicts will involve countries that can shoot down Global Hawks. It is considered cheaper to use smaller and less expensive UAVs in that kind of situation.
You'd think the RQ-4 would be somewhat perfected by now and have plenty of fans. Development of the RQ-4 began in the 1990s, as a DARPA research project. But by 2006, per-aircraft costs were 25 percent over the original price. By 2007, production schedules had slipped as well. The air force and Northrop Grumman disagreed over what caused these problems. The air force blamed it on poor management. Northrop Grumman said it's all about dealing with complex technology. The air force pointed out that the RQ-4 was not high tech. The sensors often are but they are added to the aircraft after they come off the production line. Northrop Grumman continued to stonewall the air force and showed no signs of making any basic changes.
Things started off on a more promising note. The RQ-4 was still in development on September 11, 2001, but was rushed into action. The first production RQ-4A was not delivered until August, 2003. Although the RQ-4 could stay in the air for up to 42 hours, all of them had only amassed about 4,000 flight hours by 2004. But most of those 4,000 hours, which were originally planned to involve testing of a new aircraft, were instead used to perform combat missions. Global Hawk also got to fly under difficult conditions, something an aircraft still being developed would not do.
Five years ago an RQ-4A Global Hawk made the first non-stop crossing of the Pacific, flying 12,000 kilometers from California to Australia in 23 hours. The Global Hawk has previously crossed the Pacific in several hops but it always had the endurance to do it non-stop. In the last decade RQ-4s have flown over 55,000 hours, most of that combat missions and many of them from Persian Gulf bases. The latest models can fly 20 hour missions, land for refueling and maintenance, and be off in four hours for another twenty hours in the sky. But the reliability issues with the Block 30 made the longer missions infrequent. Otherwise, the RQ-4 has been very reliable, with aircraft being ready for action 95 percent of the time. An RQ-4 can survey about 4,000 square kilometers down below an hour.
The current (B) version of the RQ-4 is about ten percent larger (wingspan of 42.3 meters/131 feet and 15.5 meters/48 feet long) than the A model and can carry an additional two tons of equipment. To support that there's a new generator that produces 150 percent more electrical power. The B version is a lot more reliable. Early A models tended to fail and crash at the rate of once every thousand flight hours, mostly because of design flaws. The first three RQ-4Bs entered service in 2006.
At 13 tons the Global Hawk is the size of a commuter airliner (like the Embraer ERJ 145) but costs nearly twice as much. Global Hawk can be equipped with much more powerful, and expensive, sensors than other UAVs. The spy satellite quality sensors (especially AESA radar) are usually worth the expense because they enable the UAV, flying at about 20,000 meters (61,000 feet), to get a sharp picture of all the territory it can see from that altitude.
Meanwhile, the U.S. Navy bought Global Hawks to perform maritime reconnaissance. This led Australia to buy some as well, to monitor the vast stretches of ocean that surround the island continent. Germany has bought the RQ-4 and South Korea wants some too. NASA uses two of them. There has been plenty of competition for RQ-4 work. In addition to the manned U-2, there is a longer (42 hours) endurance version of the five ton Reaper, as well as the jet powered version of the Reaper called Avenger. This aircraft can do 85 percent of what the RQ-4 can but costs half as much. Moreover, the Avenger is 29 percent faster, although it only has an endurance of 20 hours, compared to 35 for the RQ-4. Most importantly, the Avenger and Reaper come from a manufacturer (General Atomics) that has been much more dependable than Northrop Grumman. For the moment Global Hawk remains a player in the UAV market, mainly because of its usefulness as a maritime patrol aircraft. This may be what will save the project from cancellation. After all, the air force is not responsible for monitoring the high seas.