and their photos were very useful on the ground. An RQ-4 can survey about four-thousand square kilometers an hour. The RQ-4 that flew the Philippines missions was a Block 30. RQ-4s have been used before in disaster relief work. This included missions in 2007 (California wild fires), 2010 (Haiti earthquake aftermath) and 2011 (tracking the radiation patterns after the Japanese earthquake and tsunami wrecked a nuclear power plant).
In November 2013 the U.S. sent a Global Hawk UAV from Guam to the Philippines three times to take over a thousand detailed photos of typhoon damage. This was because of the November 8th, 2013 typhoon that killed over 7,000 people and injured over 27,000. Worse, millions of people were cut off and it was difficult to get a handle on how much damage had been done and where it all was. This was a record breaking typhoon and the Filipino government didn’t have the kind of high powered digital sensors carried by the Global Hawk. The Guam based Global Hawks flew missions over the typhoon damage on November 14th, 16th and 20
At thirteen tons the jet powered RQ-4 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. These sensors more than double the cost of the aircraft. The spy satellite quality sensors (especially AESA radar) are usually worth the expense because they enable the UAV, flying at 20,000 meters (over 60,000 feet), to get a sharp picture of all the territory it can see from that altitude.
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 forty-two hours, all of them had only amassed about four-thousand flight hours by 2004. But most of those four-thousand 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.
In 2008, an RQ-4A Global Hawk made the first non-stop crossing of the Pacific, flying twelve-thousand kilometers from California to Australia in twenty-three 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 100,000 hours, most of that combat missions, and many of them from Persian Gulf bases. The latest models can fly twenty hour missions, land for refueling and maintenance, and be off in four hours for another twenty hours in the sky.
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 ninety-five percent of the time. The current RQ-4 is the “B” version (Block 20, 30 and 40). Include payload (sensors and communications) and development costs and these cost an averages of over $120 million each. The B version 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 one-hundred and fifty 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, with some of those flaws still present, and it took over five years to clear that up. This included reducing operating costs from $41,000 an hour to under $18,000.