In pictures, U.S. Navy MQ-4C Triton UAV takes off
The 737 has, like the P-3, been equipped with bomb hard points on the wings for torpedoes or missiles. The B-737 is a more modern design and has been used successfully since the 1960s by commercial aviation. Navy aviators are confident that it will be as reliable as the P-3. (The P-3 was based on the Electra civilian airliner that first flew in 1954. Although only 170 were built, plus 600 P-3s, about 20 Electras are still in service.) The Boeing 737 first flew in 1965, and over 5,000 have been built. The P-8A will be the first 737 designed with a bomb bay and four wing racks for weapons.
The Navy is buying a modified version of the B model of the RQ-4 for over $60 million each. This version is larger (wingspan is 5 meters/15 feet larger, at 42.2 meters/131 feet, and it's nine percent longer at 15.5 meters/48 feet) than the A model and can carry more equipment. To support that, there's a new generator that produces 150 percent more electrical power. The RQ-4 has a range of over 22,000 kilometers and a cruising speed of 650 kilometers an hour.
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, which more than double the cost of the aircraft. These "spy satellite quality" sensors (especially AESA radar) are usually worth the expense because they enable the UAV, flying at over 20,000 meters (62,000 feet), to get a sharp picture of all the territory it can see from that altitude. The B version is supposed to be a lot more reliable. Early A models tended to fail and crash at the rate of once every thousand flight hours.
The maritime RQ-4 is seen as the ultimate replacement for all manned maritime patrol aircraft, at least once it is equipped with more anti-submarine sensors and weapons. The P-8A will probably be the last manned naval search aircraft. Some countries are using satellite communications to put the sensor operators who staff manned patrol aircraft on the ground. Some nations propose sending aircraft like the P-3 or P-8 aloft with just their flight crews, having all the other gear operated from the ground. This enables the aircraft to stay in the air longer and carry more gear.
Article: Strategy Page/ Photos: Xinhua News