Wednesday, June 1, 2011
Boeing AH-64 Block III
|Boeing’s AH-64 Block III features 26 performance-enhancing upgrades. Boeing|
Boeing is on track to deliver the first AH-64 Block III Apache to the U.S. Army this coming October, with the first “half dozen or so” designated for initial testing and training, according to Scott Rudy, manager of the Apache Block III program. Delivery of the first Block III aircraft to Army units will begin early next spring.
The AH-64 Block III program was officially recognized as a pre-milestone B program in June 2005. The initial contract for low rate initial production (LRIP) was signed in October 2010.
Boeing said that its Block III program integrates 26 technologies focused on “enhanced performance, operations and support cost reduction; improved target detection and acquisition; increased situational awareness and survivability; and improved maintenance/training.” However, the major upgrades are in three areas: drive train, open architecture avionics and data link capabilities to unmanned aerial systems (UAS, previously UAVs), Rudy said.
The drive train improvements are perhaps the most significant, he added. With the fielding of the D models, the pilots traded capabilities for increased weight. The new aircraft will have the same T700-GE-701 engines as both the A and D models, but upgraded from the 701C to the 701D with enhanced digital electronic control units (EDECUs) that allow the engines to obtain about a five percent increase in power. “We didn’t change the internals of the engine, but by monitoring certain parameters, we can get more thrust out of it,” Rudy said.
Boeing has also made changes to the engine nose gearboxes and main transmissions designed to increase power by 20 percent. The existing transmission on the AH-64 is 2,828 shp. Transmissions on the Block III aircraft will be 3,400 shp. Rudy noted that whereas the original D models were transmission limited, the Block III will be engine limited, depending on the regime in which the aircraft is flying. The new transmissions have oil-cooled nose gearboxes rather than air-cooled. The Block III aircraft are also getting composite blades. Composite blades are already flying on the Boeing CH-47 Chinooks and Sikorsky UH-60 Black Hawks, but not on the Apaches. “The incorporation of these new, proven technologies and enhanced capabilities in the AH-64D Block III brings a huge improvement for the soldier,” said Tommy Filler, deputy, attack helicopter programs. The second improvement to the Block III aircraft is its new ability to integrate Level III and Level IV data link connection to a UAS. Level III allows Apache pilots to control the payload of the UAV, while Level IV allows pilots to totally control the UAS, except for takeoffs and landings.
The third improvement adds open systems architecture to the aircraft’s avionics. “We’ve incorporated a different type of architecture into the Apache in terms of hardware, primarily in the mission processor … the main computer on the aircraft built by Elbit.” The open architecture hardware is designed so that hardware cards can be dropped into the mission processor. Improvements have also been made in the way the software is written inside the mission processor. This allows other third-party software to be dropped into the processor as long as it meets the interface requirements.
The current Block III program calls for a total of 690 aircraft, of which 634 will be remanufactured A and D models and 56 will be new builds. Boeing will start with the remanufactured aircraft.
Then, “about three years into the program, we will build the 56 new aircraft concurrent with the remanufacturing program. [Those 56 aircraft] will take about three years, then we will just do remanufacturing after that,” Rudy said.
He also noted that Boeing is currently in discussions with virtually all of its international customers for upgrading to Block III. “Most of the international countries are watching Block III with interest. We expect to see almost every one of them back in here for upgrades.”
International customers include Egypt, Greece, Israel, Japan, Kuwait, Netherlands, Saudi Arabia, Singapore, the United Arab Emirates, and the United Kingdom.