Tanker Time Is Tight

Jan. 27, 2016

The KC-46 tanker project has entered a critical period. In the next few months, the flying test fleet will double from two aircraft to four, test flying will accelerate, and program managers will seek Pentagon approval to begin low-rate initial production. If all that happens on time, managers in the Air Force and at Boeing believe the project will make its key deadline of delivering enough airplanes to go operational circa August 2017.

That’s just 18 months away, though, and there’s no margin left in the schedule for any newly discovered problems.

Still, if all goes well, the Air Force will soon start receiving the most advanced tanker it’s ever had—far more capable, flexible, and survivable than the KC-135s and KC-10s flying today.

“When the program was first started, … the schedule we put on contract showed [Boeing] six months early to required assets available,” said Brig. Gen. Duke Z. Richardson, USAF program executive officer for tankers. The required assets available (RAA) benchmark is 18 airplanes, needed for Air Mobility Command to declare initial operational capability in August 2017 or soon afterward.

“From their [original] schedule, they would have delivered to that six months early,” Richardson said in a December interview. However, “that six months margin … that they had baked into the schedule” is gone.

The schedule went awry when Boeing discovered it had improperly wired the first test aircraft (and some of ships two and three), failing to separate certain wires that the Air Force specified be physically set apart from each other to meet battle damage redundancy requirements. It took months to rip out the old wiring, design new bundles, and install them, making sure that subsequent airplanes on the assembly line would also meet requirements.

Another delay was incurred when there was contamination of a test fuel system, requiring weeks to disassemble, repair, and recertify it. The two problems alone ate up nearly all the six months of leeway.

This was costly for Boeing, whose management admits to bidding strategically on the fixed-price KC-46 program in 2011 to ensure a win. That meant Boeing bid less than it thought the development program would cost, expecting to make up the losses through volume efficiencies on its commercial airliner and freighter lines (especially the 767 that the KC-46 is largely derived from), by potentially winning the inside track on future USAF tanker buys and by being well-positioned for future worldwide tanker sales against its airliner nemesis, Airbus.

To date, Boeing’s after-tax losses on the KC-46 exceed $500 million. Because it is a fixed-price program, Boeing bears all liability for the overage and so has great “incentive” to stay on track from here on, Richardson observed.

“Time costs money, so the faster they can get through the program, the sooner they’ll stop the bleeding,” Richardson said.

Since those two big problems were corrected, though, the program has been moving well, according to Charles L. Johnson II, Boeing vice president for Air Force mobility programs. In a December interview, Johnson said the two tanker prototypes then flying—one a “provisioned freighter” and another fully equipped with all the KC-46’s tanker and other military equipment—had accumulated 350 flight hours on about 110 sorties. The ability to “turn the jets, do the postflight stuff, get the data downloaded, analyzed, … and then get airborne again has actually been going pretty well,” he said.

FAA Certification

The first jet flew in December 2014. Designated a 767-2C, it was based on the 767-200ER freighter, but with “provision” for the plumbing, electronics, and hard decking necessary to convert it to a KC-46 tanker. Because the KC-46 is considered a derivative, the 767-2C must be certified by the Federal Aviation Administration for airworthiness, and the test program has been designed so that FAA certifications and Air Force flight testing can be done in parallel to save time and reduce the number of flights necessary. New to this airplane from the stock 767 is a different wing design and a glass cockpit adapted from the 787 Dreamliner, among other differences.

Two 767-2Cs and two all-up KC-46s will comprise the test fleet. The two 2Cs will be converted into KC-46s later, and ultimately, all four airplanes will join the operational force. The KC-46 program calls for 179 tankers to be delivered by about 2027.

Johnson said the test fleet was designed so there would always be a spare of each type during flight testing.

Engineering, manufacturing, and development (EMD) aircraft No. 2, configured as a KC-46 with functional refueling gear and other equipment, made its first flight Sept. 25 last year. During the four-hour hop, the flight controls, engines, environmental control systems, and other apparatus were tested up to an altitude of 35,000 feet. The aircraft carries two wing aerial refueling pods. WARPs will allow the jet to refuel aircraft (typically Navy and foreign types) that use the probe-and-drogue refueling system. The WARPs deploy a hose and basket that the receiver aircraft connects to with a probe. The WARPs were tested Oct. 8, as was a hose system on the centerline. This feature will allow the KC-46 to refuel up to three aircraft simultaneously. The centerline refueling boom was deployed on Oct. 9.

Richardson and Col. Christopher Coombs, the Air Force’s KC-46 program manager, said test flights so far are going well and no major deficiencies have shown up, although “we’re a few weeks off our plan in terms of the fly rate for EMD 1 and 2,” Richardson said. He chalked that up to “standard stuff” such as a fuel leak and weather delays—things not having to do with the design of the jet. Testing of the cargo-loading characteristics of the KC-46 was done last October and revealed no problems, Johnson asserted.

The start of “dry hookups” with a series of receiver aircraft was set to begin early this year. The initial schedule called for, in order, connections with an F-16, C-17, F/A-18, A-10, AV-8B, and another KC-46. The F-16 is representative of a USAF “fast mover,” Johnson said. The C-17 is representative of a “heavy,” while the F/A-18 is a “fast mover” using the probe-and-drogue system. The A-10 is a “slow mover” boom-type receiver while the AV-8B is a slow mover of the probe-drogue type. Finally, the KC-46 is required to be able to both give and receive fuel, so there will be yet another test with a “heavy,” Johnson said.

After dry hookups, later tests will transfer fuel. A second wave of eight “receiver pairs” will follow, and a third phase will certify 11 more, Richardson explained.

The list does not yet include the F-35. Even though the strike fighter is expected one day to be the most numerous aircraft in USAF’s inventory—and possibly that of the Navy and Marine Corps as well—Richardson said a decision was made early on not to mingle two developmental programs.

“We don’t like change on this program,” he said, crediting a lack of shifting requirements with the relatively smooth progress of the project so far. Given that the F-35 was in flux when the KC-46 was mapped out, it was decided to save it for a “Phase 4” receiver pairs group.

The big programmatic hurdle ahead is Milestone C, when Pentagon acquisition, technology, and logistics chief Frank Kendall must approve starting low-rate initial production of the new tanker. If he does—that decision is expected around April—the Air Force will have the green light to award the first three year-lots of airplanes. Lot 1 will be for seven jets, and it could be awarded as early as May. Lot 2 is for 12 aircraft and it could be awarded in June. Lot 3 will have 15 aircraft.

The LRIP 1 and 2 contracts are “prenegotiated,” Richardson pointed out, “so once we get Milestone C approval, we will be able to award those immediately.” Lot 3 and beyond are not fixed price, but “they’re on what we call ‘not-to-exceed’?” contracts. When the KC-X competition was held between Boeing and Airbus in 2011, “we competed all 179 aircraft, all the way out. So I think that was a smart move by the department,” Richardson said. “We know there’s a ceiling as to how much they could cost, and we won’t go above that ceiling, by definition.”

The price could well be lower because USAF will be applying “should cost” and “should schedule” analyses to the project to determine a fair price for the jets, he added.

On Time

Though Boeing won’t have the go-ahead to begin production of KC-46s until Kendall makes his Milestone C call, “it’s very likely,” Richardson said, that the company has begun procuring material for long-lead items already.

With first contact in January—“a good sign for the program”—Milestone C, and the first LRIP contract probably happening on time, “we’re in good shape,” Richardson said.

The KC-46 is one of three programs that USAF leaders have described as “existential” for the service—the other two being the F-35 fighter and the Long-Range Strike Bomber. Tankers extend the range of most Air Force aircraft, making it possible to reach around the world and, if necessary, operate directly from bases in the US.

The need for the tanker is urgent, as USAF’s existing fleet of aerial refueling aircraft comprises 396 KC-135s Stratotankers—bought during the Eisenhower Administration—and 59 KC-10 Extenders, acquired during the Reagan Administration. Though updated over the years and scrupulously maintained, many of the jets suffer from corrosion, structural fatigue, and obsolescence.

Several separate efforts to recapitalize the tanker fleet during the 2000s failed, either due to politics or the Air Force’s own mismanagement of the effort. The KC-46 was selected in a 2011 competition against the Airbus KC-30, and the two continue to slug it out in international contests.

The KC-46 should not be considered merely a tanker, Richardson said.

“It really opens up the globe to us,” he said. “Every single KC-46 will be able to do, same sortie, boom and drogue.” Only 20 KC-135s are able to refuel both boom- and hose-type aircraft at the same time. These “have the highest number of hours” compared with the rest of the fleet “because they’re so flexible and in-demand.” Given that USAF almost always fights as part of a coalition, partnered with Navy-Marine Corps jets as well as foreign aircraft that use probe-and-drogue, the KC-46 will be a force multiplier, Richardson asserted.

He noted that only eight KC-135s can be refueled.

With a lab-demonstrated ability to pump up to 1,300 gallons per minute, the KC-46 will also be able to process jets more rapidly, each spending less time on the boom, Richardson said.

Every KC-46 will have the Large Aircraft Infrared Countermeasures (LAIRCM) laser defense system to protect against anti-aircraft missiles, and a suite of integrated defensive systems, such as a radar warning receiver, that will make the jet more survivable. Moreover, the KC-46s will be linked to USAF’s aerial networks, able to connect to Link 16 and threat advisory systems. It will have a “rerouting capability” to steer around threats, a “pretty significant capability” not found on the KC-135, said Richardson.

“It fulfills all the needs,” he said. Both to contain changes and cost, requirements have not changed on the KC-46 since the KC-X competition, but they haven’t needed to, either, Richardson said, because of the jet’s capability and flexibility. Moreover, it will have the ability to carry cargo pallets and litters for aeromedical evacuation as needed.

Unlike the KC-135 and the KC-10, the boom operator will be seated right behind the cockpit, instead of at the tail of the jet. Equipped with a 3-D imaging system, the boomer will be able to view what’s going on at the tail end of the airplane “wingtip to wingtip,” Johnson said. Flight crew will also be able to view the refueling situation on a cockpit display, another upgrade from existing tankers. Furthermore, an advanced lighting system has been developed that gives crisp illumination for receiver aircraft at night, letting them see the KC-46 in sharp detail and allowing pilots to request greater or lesser lighting intensity. For blackout or special operations, Johnson said, receiver aircraft pilots using night vision goggles will see the aircraft clearly, instead of the fuzzy images they see now. In blackout, without NVGs, the jet will be invisible against a night sky.

Safety First

The KC-46 will be “a giant step” forward as far as safety goes, Johnson asserted.

Given all that’s been accomplished so far, “there’s really not a ton of work left” to do to meet requirements for LRIP to start, Richardson said.

Flight test, however, has a way of fulfilling its purpose: revealing problems and discovering deficiencies that need to be corrected.

Coombs said USAF and Boeing are working well together to try to mitigate the risks of doing so much testing and development concurrently, and both he and Richardson believe there are “opportunities” to buy back some of the schedule margin lost so far.

One way, Richardson said, might be to streamline flight testing. Flight test results so far have been “pretty darn positive,” he said, and that may allow skipping some test points.

“We don’t ever extrapolate from one test point to the next, but we interpolate. So if we have two data points that look good, we don’t necessarily need to collect the data point that’s between the two” if they “follow the model that we had built ahead of time.”

Richardson acknowledged that this approach—applied to a much greater degree—was tried on the F-35 program with limited success, but “I wouldn’t say that’s how we’re going to make up schedule.” He praised Boeing for its skill at “moving testing around” when an issue emerges so that full use of the test assets can be made and “so that we don’t have any blank space” in the test program.

There may also be ways to do more of the required FAA testing in parallel rather than in serial fashion, and ways to speed up fatigue testing, he said.

Richardson said he doesn’t want to “oversell” the idea of interpolating test points and maintained it wouldn’t be done with a lot of the testing, but was rather more optimistic about the chances of making up some time with the FAA assessments. “A good bit of the [testing] falls into the FAA camp, because of the airworthiness process that Boeing has to go through … to get the amended type certification and the supplement type certification.”

What if an issue is discovered that delays the program? Richardson said the answer would depend on “how much they miss it by, … and how many airplanes do they miss it by?”

His portfolio encompasses all the tankers, and further delay of the KC-46 would necessarily mean an extension of the oldest and “worst actors” in the KC-135 fleet.

“We’re doing due diligence to look at those legacy fleets to answer exactly that question,” he said. “If we had to extend [the old jets] a couple of months, what does that require us to do, to still fly safely?” All that information “will go into a contract negotiation with Boeing to deal with that issue.”

Richardson didn’t discuss specific remedies, but Boeing does a lot of the KC-135 and KC-10 support and might potentially have to provide in-kind service life extension on some aircraft at reduced or no cost if it misses RAA.

He hastened to add, however, that “Boeing has not let up on their drive to meet that contractual RAA date. And so, on the Air Force side, we’re doing everything we can to help them as long as it doesn’t cost us another dime.”

When issues are discovered in flight test, it means going back and retrofitting aircraft that have already been produced and altering the production line with a fix so that new airplanes don’t have the same fault built in. In some programs, this cost is shared between the government and the contractor, but on the KC-46, Boeing is responsible for the cost of these retrofits.

Coombs explained that Boeing has the responsibility “to go back in and make corrections to any aircraft that has already been delivered … or any aircraft that is in production, of anything that is found all the way through IOT&E” (initial operational test and evaluation). The way the contract is written, Boeing will decide “when is the right time, when do they feel the engineering system is stabilized enough that everything is great to start producing those aircraft,” he said. Boeing will be mindful that “they’re in the hole, so they’re going to want to minimize any changes that they may have to incorporate later.”

Seeking the Market

Will Boeing be able to recoup its investment on the KC-46? So far, it has only won one international tanker contest—a three-airplane order for Japan. Johnson said, however, that it’s still early in the program—only prototypes are flying—and the KC-46 will be in production, at a rate of at least 15 a year, for at least the next 12 years. Some of the international contests the KC-46 didn’t win were for countries that needed a tanker right away, he asserted.

“There’re still opportunities out there,” he said, and Boeing believes the tanker market will increase beyond those countries that have already expressed an interest in buying some.

“Even humanitarian aid” missions are requiring tanker support now, he said, and countries that want to respond—or provide their own tanker capability in wartime coalitions—are seeing the need to have their own tankers, he said.

In his own opinion, Johnson said, many US partner countries may realize they’ve been “taking for granted” that they can get refueling support from the Air Force when they need it.

“That’s changed so much, now,” he observed. “There’s so much going on that not everybody can count on” a spare USAF tanker to help them get where they’re going. And “certain key allies want more independence to do what they want to do.” Many countries are buying the F-35, he said, and “how are you going to get to the fight? … How are you going to sustain the fight? Gotta have a tanker.”

He added, “The market is out there” and because the KC-46 will be in production a while, “they don’t have to decide right now.”

Boeing also built the C-17 airlifter and had an arrangement with the Air Force that USAF would give up some of its slots on the production line to accommodate allies that wanted to buy C-17s for themselves. The benefit to the Air Force was that the C-17 production line stayed open longer, providing an option for increased production if wartime needs demanded it. Such an arrangement might well be made with the KC-46, especially if USAF is delayed in pursuing the next phase of tanker modernization, known as the KC-Y.