If you ask
, it is on the cusp of delivering a game-changing tanker capability to the U.S. Air Force. But if you ask the Air Force, Boeing has to resolve significant design flaws and is far from completing the required flight testing.
More than seven years after contract award, the aerospace giant and its U.S. government customer are at loggerheads over the new
refueling tanker’s delivery timing and what work remains for Boeing to do.
The daylight between Boeing and the Air Force on the KC-46 refueling tanker was on full display during interviews with officials from both in the past few weeks. During a media visit to Boeing’s Everett, Washington, facility May 3 and an interview with Air Force KC-46 program manager Brig. Gen. Donna Shipton May 9 at the Pentagon, officials presented contradictory information on the long-delayed aircraft.
This is not the first time the two parties have clashed on the KC-46. Until last December, Boeing was promising to deliver the first of 18 required tankers by the end of 2017, although the Air Force was projecting it would not receive the aircraft before mid-2018.
Today, Boeing Defense CEO Leanne Caret pledges delivery of all 18 KC-46s will occur by year-end. But the Air Force now expects delivery in May 2019, 21 months later than originally planned, according to a recent report by the
.
In the meantime, Boeing has racked up more than $3 billion in pre-tax charges on the program, including an additional $81 million in the first three months of this year.
Shipton attributes the delay to Boeing’s slower-than-anticipated pace in accomplishing the required test points. Progress has been impeded by a series of technical challenges over the course of KC-46 development, she says.
There are currently two deficiencies the Air Force characterizes as “Category 1—Urgent,” meaning the problem is not a safety issue but “has no known acceptable workaround” (as opposed to “Category 1—Emergency,” meaning the problem presents a safety risk).
The most pressing issue is improving the
Remote Vision System (RVS), an advanced sensor suite that allows the crew to operate the refueling boom remotely from near the cockpit. In certain flight conditions, shadows or glare from the Sun can distract the boom operator, according to Mike Gibbons, Boeing’s KC-46 vice president and program manager. The Air Force is concerned that this can cause contact outside the receptacle, the formal term for what happens when the boom accidentally scrapes receiver aircraft.
“Learning will continue to take place once the aircraft is delivered. However, if limitations were to exist with the KC-46, they can’t be passed on to a 19-year-old boom operator to figure out,” says Air Mobility Command spokesman Col. Chris Karns. “This is more than an aircraft; it is a weapon system.”
Boeing recently began flight tests on a software “enhancement” to the RVS that it expects will reduce the number of such incidents, Gibbons says. The software upgrade sharpens the image displayed to the operator and eliminates the glare, he notes.
But the Air Force takes issue with the word “enhancement.” The change is a “fix,” says Shipton. “Something that’s an enhancement means that it’s gotten better above the requirement. We didn’t believe that the original system was going to meet the requirement, so for us this is a software fix because it fixes what we saw as a deficiency in the system in order for them to get to an acceptable level of performance.”
For the Air Force, the rate of “undetected” contacts outside the receptacle on the original RVS was excessive and did not meet the requirement that “the [air refueling operator (ARO)] shall have sufficient visual cues to safely refuel a receiver in all ambient lighting and background conditions.” The rate should be zero—any time there is contact outside the receptacle, it needs to be recorded, according to the Air Force.
Further, the contract also includes an “equivalency requirement” stating that the KC-46 must be able to refuel all receivers that are compatible with the KC-135, with no restrictions or modifications to the receiver envelope, Shipton adds. When the undetected contact issue was discovered, the Air Force was concerned that the KC-46 equipped with the original RVS would not be able to meet that requirement—including refueling stealth aircraft with low-observable coating that might be damaged.
“We did not believe that there was sufficient visual acuity in order for the ARO to safely aerial refuel on the old baseline,” Shipton says.
Boeing, by contrast, asserts that the original system met the Air Force’s requirement. “We are very happy with our camera system; it is a state of the art camera system,” Gibbons says. “Contact outside the receptacle, which has also been termed ‘boom scraping’ in some cases, actually is, unfortunately, a phenomenon that occurs in the fleet today and in test. As long as you have a person in the loop, you will end up in some conditions where you will end up contacting outside the receptacle.”
Sean Martin, Boeing KC-46 chief air refueling operator, moreover contends that the shadow and glare issue occurs in only 5-8% of tanking operations.
But that rate is too high for the Air Force. “We can’t have the 5% with restrictions because there may be very important missions where we have to refuel in those lighting conditions where a KC-135 can do it today but a KC-46 can’t,” says Col. John Newberry, KC-46 system program manager.
Boeing and the Air Force are also clashing over the results of their comprehensive joint study of the legacy fleet. Gibbons says the data shows that the rate of undetected contacts on the KC-46 is in the same range as on the existing KC-135 and KC-10 tankers. But Shipton disputes this, saying that, to her knowledge, Boeing has not yet delivered the results of the study to the Air Force.
Either way, Boeing is paying to upgrade the RVS software and will deliver the first aircraft with that modification in place, officials say.
The two parties also differ over the delivery schedule for the 18 aircraft contractually required by October. Boeing officials said during the media visit that the company could deliver all 18 tankers in quick succession. But Shipton says the two parties have agreed on a schedule after first delivery of accepting aircraft at a rate of three per month, or about every 10 days, which is a “surge” for the Air Force. The number of tankers the Air Force can accept at once is limited by the government’s rigorous acceptance process, as well as by the number of aircrew and maintainers that are trained on the aircraft, she says.
There may be opportunities to increase that rate, but not until at least after the first three aircraft are delivered, Shipton says.
“What we have said to Boeing is: first, let’s get to three; let’s show that we can do three repeatedly, and then we will look at potentially trying to do more,” Shipton says.
If you do the math, the three-per-month rate means Boeing is already late for the October deadline.
The Air Force and Boeing are united in working to expedite delivery of the first tanker. The program is considering changing a contractual requirement to certify eight receiver aircraft on the new KC-46 baseline before delivery to just three, Shipton says. All eight would be required by the start of initial operational test and evaluation, the aircraft’s final test period, she says.
Today, Boeing has 34 tankers in some stage of production and is about 95% complete with flight testing, according to company officials. The KC-46 program also has submitted the required flight-test data and reports to the
for review in advance of the expected Supplemental Type Certificate award, the last of two FAA certifications necessary for delivery.
But there is still a lot of work to be done before first delivery, says Shipton. The KC-46 must also obtain a Military Type Certificate, which is based on the FAA certifications and requires additional flight tests.
If Boeing does not deliver the first tanker by October, it would be the second time the company has missed the Required Assets Available deadline, originally slated for August 2017. To compensate for the delay so far, Boeing is providing additional training for KC-46 aircrew and maintainers above the contractual requirement. If the aircraft maker misses the deadline again, the Air Force will likely require additional compensation.
