The U.S. Army last month rolled out the latest upgrade to Boeing's iconic Apache attack helicopter—the AH-64D Longbow Block III. The version includes at least 25 technology upgrades and, importantly, interoperability with unmanned aerial systems (UAS) that permits a pilot in flight to control a drone, tap into its streaming video and use its sensors for target engagement.

The AH-64D Block III will reportedly be the only aircraft with such a capability.

This lets a pilot build situational awareness and reduce targeting and engagement time, speeding the response when alerted to an event or to troops in combat, says Lt. Col. Dan Bailey, product manager for the Apache Block III program. “I can use the UAS sensors as my sensors for weapons engagement,” he remarks. “The data link [between helicopter and UAS] shares target information and lets me upload ballistic solutions to the Apache.”

This is possible through installation on Block III Apaches of the high-bandwidth UTA—short for UAS Tactical Common Data Link Assembly—developed by Longbow LLC, a joint venture between Lockheed Martin and Northrop Grumman. The UTA has been successfully flight-tested on an Apache with a General Atomics Gray Eagle MQ-1C UAS.

Its use on the Block III helicopter means pilots will no longer rely on voice information from UAS operators for situational awareness. Referencing his own combat experience, Bailey says that during a 2006-07 deployment to Iraq, Apache pilots had no interoperability with drones beyond voice contact with ground operators. “We'd spend time having UAS operators talk us onto a target.” As a result, identification and engagement wasn't possible until the Apache crew was on top of a target. A pilot now will be able to control the flight path of a UAS, sending it well in front of his aircraft to avoid danger, view streaming video and upload sensor data.

Bailey declines to disclose the interoperability range between Apache and UAS. He notes, however, that the UTA's capabilities exceed the Block III upgrade requirement. “We tested and qualified the UTA at more than two times over spec for range, which would be sufficient for a deep attack,” Bailey says. “The requirement for UTA performance provides [a crew with] ample lead time—the end result is more than two times that.”

Another important upgrade to the Block III Apaches involves high-hot operation. The helicopters are being refitted with T700-GE-701D engines from GE Aviation, which generate 3,400 shp, and with new composite blades that increase lift and speed. The Block III will be able to hover at 6,000 ft. at 95F with a 3,400-lb. payload. The previous maximum hover altitude at 95F was 4,000 ft. with less payload. Combat speed will be 164 kt., an increase of 20 kt.

The blades and spars are made entirely of composites—the spar is also hollow, which Bailey says makes it lighter than the previous spar, more flexible and better able to maintain a sustainable bend under dynamic load. The new blades are 6 in. longer than current ones and have a slightly different swept tip, both of which increase lift. The chord and chamber are virtually unchanged from those of legacy blades. The trim tabs on the trailing edge of the blades have been modified to extend performance.

The Army Acquisition Objective (AAO) calls for 690 Block III Apaches through 2026. Of these, 56 will be new builds and 634 remanufactured. The work is being done at the Boeing plant in Mesa, Ariz.

Bailey says looming budget cuts won't affect the total number of Block IIIs in the AAO. “If there is reduced funding it will mean fewer helicopters in a given year, the number of which will be added to the end of the program.” Budget cutbacks, therefore, will “expand the timeline” of the program but not affect the total number of Block III helicopters.

The program, which began in 2006, has been “very successful,” he adds. “It is on cost and on schedule.” Follow-on development began this year, and will result in enhancements that will be added through 2017, Bailey says.

In addition to the AAO, several international customers are interested in the AH-64D Block III. One country, in fact, is on contract, though Bailey declines to disclose information about the deal beyond saying initial deliveries will begin this year. Many foreign sales will be new, and some will be remanufactures.