Integrating commercial and military avionics into the U.S. Air Force’s new KC-46A aerial refueling tanker will be a significant challenge, so program leaders are keeping an especially close eye on that effort, according to the general who oversees the aircraft’s development.
The program, with prime contractor Boeing, will integrate a new aerial refueling operator station, fuel transfer equipment, defensive systems, flight deck displays of the Boeing 787 and a host of other items into a Boeing 767-2C commercial airframe. The KC-46A also features a modernized KC-10 boom with a fly-by-wire control system, and an extended refueling envelope.
“Overall in the program, the biggest risk that Boeing has and the biggest risk we have is schedule, and one of the pieces of that risk is the avionics and the software, so we’re watching that carefully,” said Maj. Gen. Christopher Bogdan, the Air Force’s KC-46 program executive officer. “As much as we want to believe that a good portion of the avionics on this airplane comes from the commercial backbone and won’t change, the fact of the matter is when you start overlaying the military applications on it, it gets to be a little bit complicated.”
Boeing is moving through the development of the long-awaited tanker, which completed the preliminary design review in April. Future milestones include the establishment of system integration laboratories (SIL) later this year and critical design review, which is scheduled for July 2013.
Bogdan said he was impressed at the program’s preliminary design review Boeing was able to show how it plans to integrate some of the military capabilities into the commercial software.
“You usually don’t see that kind of detail until you get toward” a critical design review, he said. “But there’s a long, long way to go with the avionics on this program. Some of the requirements we have are pretty stringent.”
Rockwell Collins is supplying much of the avionics systems for the tanker, including four 15.1-inch LCDs developed for the 787 Dreamliner, tactical situation awareness system, which combines the traffic alert collision avoidance system, Mode S transponders, terrain awareness warning system and weather radar functions into a single unit, and UHF-VHF radios/tactical airborne navigation system. Other avionics suppliers include Raytheon (military GPS portion of the navigation system); Honeywell (air data inertial reference unit); Thales (integrated standby flight display); GE Aviation (flight management computer); and Teledyne Controls (aircraft condition monitoring system software and digital flight data acquisition unit). More
Maureen Dougherty, Boeing’s KC-46 vice president and program manager, said the program is using as many existing components as possible to reduce risk. “We have tried to maximize the use of existing and certified commercial avionics and military avionics … and only make those changes that are required to integrate them.”
“Boeing underestimated the amount of work that was going to be required to integrate the avionics and the software on this program” and fell “a couple months” behind, but the company recognized the problem “fairly early on” and is “working very hard to try to catch up,” Bogdan told Avionics Magazine. Boeing tapped about $30 million from a reserve account to speed up software development and has remained committed to staying on schedule for the three SILs it is building in Seattle, he said. The first two SILs are slated to start testing commercial and military hardware and software in October. The third lab, which is to begin testing in April 2013, will have a flight deck and an aerial refueling operator station and look like the inside of an airplane.
“The question is, can they get the hardware delivered from their suppliers and can they integrate that appropriately in enough time for us to keep the program on track, and that remains to be seen still,” Bogdan added. “The risk of them not meeting those SIL dates is probably low to moderate.”
Tough tasks ahead include providing the ability to keep classified and unclassified information separate, and integrating military satellite communications and data links into the aircraft. Both are considered hard to do because the 767 was not designed for those capabilities.
While Boeing is due to deliver the first 18 KC-46As by 2017 and a total of 179 tankers by 2027, the Air Force is in the early stages of developing requirements for KC-Y, the tanker the service might buy after the KC-46A. One of the capabilities being considered for KC-Y is aerial refueling of unmanned aircraft, such as Global Hawk.
“Probably by about the time we start delivering the first KC-46s, which is somewhere in the 2016-2017 point, we will start putting the framework on what we’re doing for KC-Y,” Bogdan said.
Meanwhile, the Air Force is evaluating industry bids to develop, build and support the KC-46 Aircrew Training System. A contract award of about $2 billion is expected by Dec. 31. Bogdan declined to say which or how many companies are competing, but Boeing, CAE and Lockheed Martin all confirmed they submitted proposals. L-3 Communications and FlightSafety have also been mentioned as potential competitors; FlightSafety declined to comment, and L-3 did not respond to requests for comment.