Boeing KC-46 Pegasus
|Boeing KC-46A prototype takes off from Paine Field on a test flight in July 2015.|
|Role||Air-to-air tanker, strategic airlift|
|First flight||25 September 2015|
|Primary user||United States Air Force|
|Developed from||Boeing KC-767|
The Boeing KC-46 Pegasus is a military aerial refueling and strategic military transport aircraft developed by Boeing from its 767 jet airliner. In February 2011, the tanker was selected by the United States Air Force (USAF) as the winner in the KC-X tanker competition to replace older KC-135 Stratotankers. The first 18 combat-ready aircraft are scheduled to be delivered to the U.S. Air Force in early 2018 under the terms of the development contract.
The U.S. Air Force ran a procurement program to replace around 100 of its oldest KC-135E Stratotankers, and selected Boeing's KC-767. The Boeing tanker received the KC-767A designation from the United States Department of Defense in 2002 and appeared in the 2004 edition of DoD model designation report. The Air Force decided to lease 100 KC-767 tankers from Boeing.
Despite several nations leasing military aircraft, there was criticism. US Senator John McCain and others criticized the draft leasing agreement as being wasteful and problematic. In response to the protests, the Air Force struck a compromise in November 2003, whereby it would purchase 80 KC-767 aircraft and lease 20 more. In December 2003, the Pentagon announced the project was to be frozen when an investigation of allegations of corruption led to the jailing of one of its former procurement executives who applied to work for Boeing. The Air Force's KC-767A contract was officially canceled by the DoD in January 2006.
USAF KC-X Program
In 2006, the USAF released a request for proposal (RFP) for a new tanker program, KC-X, to be selected by 2007. Boeing had also announced it may enter an even higher capability tanker based on the Boeing 777, named the KC-777 Strategic Tanker. Airbus partnered with Northrop Grumman to offer the Airbus A330 MRTT, the tanker version of the A330, which was being marketed to the USAF under the company name, KC-30.
In late January 2007 the USAF issued the KC-X Aerial Refueling Aircraft Request for Proposal. The RFP called for 179 (4 system development and demonstration and 175 production) tankers, in a contract worth an estimated US$40 billion. However, Northrop and EADS expressed their displeasure at how the RFP was structured and threatened to withdraw, leaving only Boeing to offer an aircraft.
On 12 February 2007, Boeing announced it was offering the KC-767 Advanced Tanker for the KC-X Tanker competition. Boeing stated that for KC-X's requirements, the KC-767 was a better fit than the KC-777. On 11 April 2007, Boeing submitted its KC-767 tanker proposal to U.S. Air Force. The KC-767 Advanced Tanker offered for this KC-X round was based on the in-development 767-200LRF (Long Range Freighter), rather than the -200ER on which Italian and Japanese KC-767 aircraft are based differing by combining the -200ER fuselage, -300F wing, gear, cargo door and floor, -400ER digital flightdeck and flaps, uprated engines, and "sixth-generation" fly-by-wire fuel delivery boom. The KC-767 uses manual flight control, allowing unrestricted maneuverability to avoid threats anywhere in the flight envelope.
Boeing submitted the final version of its proposal on 3 January 2008. On 29 February 2008, the DoD chose the Northrop Grumman/EADS KC-30, over the KC-767. The KC-30 was subsequently designated KC-45A by the Air Force. Boeing submitted a protest to the United States Government Accountability Office on 11 March 2008 and began waging a public relations campaign in support of their protest. On 18 June, following a series of admissions by the Air Force on the flaws in the bidding process, the GAO upheld Boeing's protest and recommended the contract be rebid. On 9 July 2008, Defense Secretary Robert Gates announced that the Air Force would reopen bidding on the tanker contract. Secretary Gates put the contract for the KC-45 into an "expedited recompetition" with Defense Undersecretary John Young in charge of the selection process instead of the Air Force. A draft of the revised RFP was provided to the contractors on 6 August 2008 for comments. By mid-August the revised RFP was to be finalized. However, on 10 September 2008, the U.S. Defense Department canceled the KC-X solicitation.
On 24 September 2009, the USAF began the first steps in the new round of bids, with a clearer set of criteria, including reducing the number of requirements from 800 to 373 in an attempt to simplify the process and allow a more objective decision to be made. On 4 March 2010, Boeing announced it would bid the KC-767 tanker for the new KC-X round. EADS announced in April 2010 it would submit a tanker bid without Northrop Grumman as a U.S. partner. Boeing submitted its KC-767 "NewGen Tanker" bid on 9 July 2010. The company submitted a revised bid on 10 February 2011.
In addition to the KC-X, observers speculate that a modified KC-46 will be used as the basis of the KC-Y tanker program, the second step of the Air Force's three-step tanker renewal plan, as altering the KC-46 process and replacing it with something entirely new is likely too big of a risk.
Selection and early development
On 24 February 2011, the Air Force announced the selection of Boeing's KC-767 tanker bid. The aircraft was designated KC-46A. Boeing was also awarded a development contract for the tanker. The contract calls for Boeing to complete and deliver 18 initial operational KC-46 tankers by 2017. The Air Force is seeking to receive a total of 179 new tankers. Boeing's "NewGen Tanker" is based on the 767-200 with an improved version of the KC-10 refueling boom, and cockpit displays from the 787.
In late June 2011, it was reported that development costs were projected to overrun by about $300 million. Boeing would be responsible for this amount, which exceeds the contract cost cap of $4.9 billion. In July 2011, revised cost projections indicated a reduced cost overrun. In March 2015, the program cost for development and procurement of 179 tankers was projected to total US$43.16 billion.
In 2013, the USAF added additional crews and flight hours for the aircraft to their future plans in response to a review that showed that the best of current plans did not take full advantage of the KC-46's cargo and aeromedical evacuation advantages over the KC-135.
On 21 August 2013, Boeing and the Air Force completed a critical design review (CDR) for the KC-46. The CDR was held from 8–10 July, and was completed one month ahead of the original schedule, which planned on the review to be finished on 24 September. With the CDR complete, the KC-46 design was set and production and testing could proceed. Assembling of the wing for the first aircraft began on 26 June 2013. Flight testing of the Boeing 767-2C airframe, which would be reconfigured into the KC-46, was scheduled to begin in mid-2014. The first fully equipped KC-46 tanker was projected to fly in early 2015. The contract calls for Boeing to build four test aircraft and deliver 18 combat-ready tankers by August 2017. The Air Force intended to buy 179 KC-46s, with all delivered by 2028.
On 12 December 2013, Boeing joined the wings and fuselage for the first 767-2C to be adapted into a KC-46A. On 23 December 2013, the first two PW4062 engines were delivered. The first of four 767-2C provision freighters were to complete assembly by the end of January 2014. Once assembled, it would go through ground vibration and instrumentation testing and have body fuel tanks added. The first test flight would occur during summer 2014 and include measuring its rate of climb and descent. The Engineering Manufacturing and Design (EMD) model would be integrated with instrumentation, electronics, and technologies needed to become a military-standard KC-46A by January 2015. Seven low-rate production KC-46s are to be delivered in 2015, 12 in 2016, and 15 delivered annually from 2017 to 2027. The KC-46A can carry 212,299 lb (96,297 kg) of fuel, 10 percent more than the KC-135, and 65,000 lb (29,000 kg) of cargo. It has both a probe and drogue and a boom and receptacle to conduct multiple refueling missions on a single mission. Survivability is improved with infrared countermeasures and the aircraft has limited electronic warfare capabilities. The airframe can be configured to carry 114 passengers and to serve as an aero-medical evacuation aircraft. The last of four test aircraft began assembly on 16 January 2014.
In April 2014, the Government Accountability Office (GAO) found that the KC-46 program was projected to underrun its projected cost estimate of $51.7 billion by $300 million. The program acquisition unit cost per jet will also be $287 million, $1.8 million less than estimated. The GAO noted that delays in training air crew and maintainers could cause testing to slip 6–12 months, but also stated that the program had not missed any major milestones and that the development of about 15.8 million lines of software code was progressing as planned. In May 2014, the Air Force estimated the cost of the development program, including the first four aircraft, could rise from $4.4–4.9 billion to $5.85 billion.
In July 2014, Boeing recorded a $272 million pre-tax charge to cover a redesign of the tanker's wiring. The wiring issue arose when it was found that 5-10% of the wiring bundles did not have sufficient separation distance or were not properly shielded to meet an Air Force requirement for double or triple-redundant wiring for some mission systems. In September 2014, it was confirmed that the wiring redesign would delay the first 767-2C flight from June 2014 to November 2014. The 767-2C's first flight took place on 28 December 2014; it flew from Paine Field and landed at Boeing Field.
In July 2015, Boeing announced that it had taken a further $835 million pretax charge to pay for redesigns and retrofits required to address a faulty integrated fuel system. A Boeing spokesperson stated that “in preparing for and performing fuel system qualification testing, we identified a number of fuel system parts and components that did not meet specifications and needed to be redesigned. We’re adding the engineers and ancillary staff resources needed to support the engineering redesign, manufacturing retrofit and qualification and certification of the fuel system changes, and the conclusion of functional and flight testing." Boeing may have to wait an extra eight months for $3 billion in contracts on the KC-46 because of delays caused by the wiring and fuel system parts flaws, according to the USAF. Low-rate production contracts to build the first 19 of the tankers may be delayed from August to as late as April 2016 in the latest schedule revision agreed on by the Air Force and Boeing. The planned first flight of a fully equipped KC-46 is being delayed to as late as September 2015. Air Force Spokesman, Charles Gulick, noted that the primary goal, "delivery of 18 tankers by August 2017" can be met. The Bank of America/Merrill Lynch noted in July 2015 “We fail to understand how Boeing could take a $1.26 billion pre-tax charge (since it won the contract over Airbus) on the Boeing KC-46A program since the program is based on the 767 airframe that has been in production for over 30 years.”
On 24 January 2016, the KC-46 successfully refueled an aircraft for the first time during a 5-hour 36 minute sortie just over the shared coast of Washington state and Oregon. This refueling was with an F-16. Next the KC-46 will test refueling a number of other military aircraft, including a C-17, F/A-18, A-10 and AV-8B. On 10 February, a test KC-46 refueled a F/A-18 in the first via its probe and drogue system.
On 22 March 2016, it was reported that the DoD's Defense Contract Management Agency had "low confidence in Boeing’s ability" to meet the August 2017 deadline. The agency predicts that the first 18 refueling aircraft would be delivered about seven months late, by March 2018. This is based on "past performance, current risks", such as delays in production, its assessment of new joint Air Force-Boeing schedule review, and the uncertainties with flight testing. The agency may revise its schedule estimate by June 2016. The Pentagon’s test office is to begin the tanker’s combat testing in late April 2017.
In March 2015 a refueling test with a C-17 transport aircraft was stopped because of a higher-than-expected boom axial load while delivering fuel. A Boeing spokesman stated "We don't yet know the schedule impact to the planned May (2016) Milestone C decision, but the problem is well understood and we don't expect an extended delay." The problem was caused by the turbulent "bow wave effect" generated by two large aircraft flying in line.
The April 2016 Report from the U.S. Government Accountability Office (GAO) described Boeing’s test schedule for the KC-46 program as “optimistic” and projects Boeing will need an additional four months beyond the August 2017 target to deliver 18 full-up tankers due to testing and parts qualification issues. The report notes that operational testing will not now begin until May 2017 and will not be completed until two months after the first tranche of 18 aircraft are delivered, risking late discoveries of problems. The GAO also noted that Boeing has not obtained Federal Aviation Administration's approval for two key aerial refueling systems - the centerline drogue system and the wing aerial refueling pods, which were built without following FAA processes. Boeing now projects these components will be ready for the FAA to certify by July 2017 — over three years late. The 18 aircraft were meant to include the four developmental aircraft, brought up to an operational standard, plus the first 14 low-rate production (LRP) examples. Instead, 16 of the 18 will be production line examples; because the aircraft will be delivered before operational testing is complete, Boeing will be responsible for any late design fixes.
In April 2016, Boeing announced that it would closely integrate its 767 and 747 programs. Bruce Dickinson, Vice President and General Manager for these programs said "The 767 production line is quite full, so the pressure we see for that is growing. We are getting to the point where we will see by next year the line alternating as tanker-freighter-tanker-freighter." More aircraft will be assembled on the 767 line in 2016 than delivered. About 22 KC-46 aircraft are to be built and an estimated 13 delivered during the year.
On 25 April 2016, the fourth test aircraft, 767-2C EMD-3 first flew. It performed operational engine checks, flight controls, and environmental systems checks, while flying to a maximum altitude of 39,000 ft. EMD-3 will conduct environmental control system testing, including hot day/cold day testing and smoke penetration testing.
On 27 April 2016, Boeing took another pre-tax charge for cost overruns on the program of $243 million, bringing the total amount Boeing has paid for tanker-related cost overruns to $1.5 billion to date. "This third charge allows Boeing to maintain schedule with concurrency between late-stage development testing and the transition to initial production." The charge will be split between Boeing Commercial ($162 million) and Boeing Military ($81 million). Boeing president and chief executive Dennis Muilenburg stated that 80% of the test points required for a positive Milestone C decision had been completed.
On 3 May 2016, US Air Force spokesman Daryl Mayer confirmed that Milestone C review was now expected to occur in June, "subject to completion of flight test verification" of a fix to refueling system glitches. "The problem is well understood." A spokesman for the US Air Force’s tanker directorate at Wright-Patterson AFB, Ohio also confirmed that flight testing being conducted will help determine whether the fault can be resolved with a software tweak, or a potentially more difficult hardware change. Boeing has been working hardware and software solutions in parallel. “Boeing is flight testing a software fix to the boom axial loads issue now; once that fix is fully verified in flight, the C-17 and A-10 refuelling demonstrations will begin, which we anticipate to occur in late May."
On 26 May 2016, it was reported that the program would face a further delay of at least six months, due to "technical and supply chain problems". This might require the program to be re-structured or for funding to be cut, either by Congress or the Pentagon. At this time, Boeing has only completed 20% of the development flight tests. A report from The Senate Appropriations Committee on the fiscal 2017 defense spending bill, issued on the same day, expressed concerns about the aircraft's future. The initial 18 aircraft are to be equipped with the refueling boom and centerline drogue, but not the wing-mounted wing-aerial refueling pods (WARP). The WARP systems, which are required to complete full contractual Required Assets Available (RAA), will be delivered separately in October 2018. Boeing stated "The underlying production system remains on track, and Boeing will have more than 18 aircraft through the factory line and in various stages of final change incorporation and certification by August 2017."
On 2 June 2016, USAF spokesman Maj. Rob Leese confirmed that, while the Air Force's KC-46 contract with Boeing does not contain any pre-defined penalties for schedule delays. Not delivering the 18 certified tankers by August 2017 is a contract schedule breach. "The Air Force will secure consideration from Boeing as part of the schedule re-baseline that is about to commence following the RRA delay announcement." On 12 July 2016, Frank Kendall, US Defense Acquisitions Chief, confirmed that the tanker program office was analyzing the likely costs for the service arising from the delay. "The government is losing some of the value that we have contracted for, so we are entitled to some consideration for that. The program office has several ideas for how we might do that, and they’re talking to Boeing." The USAF would incur additional costs were it necessary to operate the KC-135 fleet for longer than planned.
On 8 June 2016, Boeing's defense unit CEO, Leanne Caret, reported that a modified boom would be flown the following month. A hydraulic relief valve system would be installed so that if loads build up on the boom, the valves open to relieve the pressure. The system is similar to equipment used on the booms of the KC-10 and KC-767 tankers. On 10 July 2016, Caret reported 'positive' early results after flight tests with the revised boom commenced the previous week.
On 5 July 2016, Air Force spokesman Daryl Mayer stated that while KC-46 developmental testing was moving “slower than planned,” the program was on track to hit Milestone C the following month. He also stated that Boeing would add a fifth engineering and manufacturing development (EMD) aircraft to the fleet to accelerate the flight test program. EMD-1 and EMD-3 are primarily conducting flight tests required to secure FAA airworthiness certificates, while EMD-2 and EMD-4 are primarily focused on Air Force aerial refueling and other mission system testing.
An F-16 was successfully refueled on 8 July, and a C-17 on 12 July 2016. Once the hardware fix is verified, a KC-46 with the updated boom will complete regression testing on the F-16, followed by refueling demonstrations with the C-17 and A-10 to meet the final test for Milestone C approval. USAF chief of staff, General David Goldfein, commented "While it took some time, this week's results confirm my confidence the Boeing team will get this figured out. It's reassuring to see the program take this important step toward the production decision in August." On 15 July 2016 the KC-46 successfully refueled an A-10; during a four-hour flight, the KC-46 offloaded 1,500 pounds of fuel at 15,000 feet. "This completed the required air refueling demonstrations needed for the upcoming production milestone decision," said Boeing spokesman Chick Ramey. To date, more than 900 flight test hours have been completed with the five test aircraft.
On 21 July 2016, Boeing stated it would take a further $393 million charge on the KC-46 tanker program, bringing the total value of penalties to almost $1.9 billion. The charge reflects higher costs associated with the program’s current schedule and technical challenges, which include "implementation of the hardware solution to resolve the refueling boom axial load issue identified during flight testing, delays in the certification process and concurrency between late-stage development testing and initial production."
On 12 August 2016, the KC-46 program received Milestone C approval from the undersecretary of defense for acquisition, technology, and logistics, indicating that it is ready to enter production. Boeing was expected to receive initial contracts for two lots of 19 aircraft total in the next 30 days. 18 aircraft are scheduled to be delivered to the air force by early 2018.
In September 2016, Air Mobility Command announced they were abandoning plans to have the follow-on KC-Y acquisition program to replace the remainder of the KC-135 fleet, instead turning it into a "bridge" for further KC-46 orders with some upgrades.
On 23 April 2014, the USAF announced that the KC-46 Pegasus will be based at McConnell Air Force Base in Wichita, Kansas. The base will start receiving the first of 36 tankers in 2016. The KC-135 Stratotanker is currently stationed at this base. McConnell AFB was chosen because it had low construction costs and it is in a location with a high demand for air refueling. Up to 10 operating bases are to be chosen for the KC-46 fleet. Pegasus crews will be trained at Altus Air Force Base, Oklahoma. Altus AFB was also chosen for its limited construction needs and for other training programs for the C-17 Globemaster and KC-135 already at the base.
On 29 October 2015, the USAF announced that Seymour Johnson Air Force Base, North Carolina, was chosen as the preferred alternative for the first Reserve-led KC-46A Pegasus main operating base. The KC-46As will begin arriving at Seymour Johnson in fiscal year 2019. Tinker Air Force Base, Oklahoma; Westover Air Reserve Base, Massachusetts; and Grissom Air Reserve Base, Indiana, were named as the reasonable alternatives. The Air Force plans to begin the Environmental Impact Analysis Process (EIAP). Once the requirements of the EIAP are complete, the Air Force will make its final basing decision.
In June 2014, Boeing submitted the KC-46 for the Republic of Korea Air Force's requirement for four aerial tankers. The KC-46 competed with the Airbus A330 MRTT, and South Korea selected the Airbus A330 MRTT in June 2015.
Boeing pitched the KC-46 to the Polish Air Force for their tanker requirement. In December 2014, Airbus was awarded a contract for four A330 MRTTs from a consortium of Poland, the Netherlands, and Norway.
On 23 October 2015, the Japan Air Self-Defense Force selected the KC-46 as their new tanker, with a contract for three tankers expected in 2016. The decision allows for common operations and training with the USAF, and Japan was reportedly attracted to its capability to refuel MV-22 Osprey tiltrotors the JASDF will soon receive. Airbus declined to bid their A330 MRTT, because they viewed Japan's request for proposals as intended for the KC-46. The three tankers are to be fielded around 2020 at a cost of more than ¥20.8 billion, about US$173 million per aircraft.
On 2 February 2017, Boeing stated it would bid the KC-46A for the Royal Canadian Air Force's Strategic Tanker Transport Capability competition, a project to replace Canada's fleet of CC-150 Polaris tanker aircraft. The contract is valued at C$1.5+ billion.
- United States Air Force
- 418th Flight Test Squadron (AFMC) - Edwards AFB, California
- 97th Air Mobility Wing (AETC) – Altus AFB, Oklahoma (aircrew training)
- 22d Air Refueling Wing (AMC) – McConnell AFB, Kansas (planned host site)
- 157th Air Refueling Wing (ANG) – Pease ANGB, New Hampshire (planned host site)
- 916th Air Refueling Wing (AFRC) – Seymour Johnson AFB, North Carolina (planned host site)
- Crew: 3 (2 pilots, 1 boom operator) basic crew; 15 permanent seats for additional/optional air crew members, including aeromedical evacuation crew members
- Capacity: seating for up to 114 people, 18 463L pallets, or 58 patients (24 litters, 34 ambulatory)
- Payload: 65,000 lb (29,500 kg)
- Length: 165 ft 6 in (50.5 m)
- Wingspan: 157 ft 8 in (48.1 m)
- Height: 52 ft 1 in (15.9 m)
- Empty weight: 181,610 lb (82,377 kg)
- Max. takeoff weight: 415,000 lb (188,240 kg)
- Fuel Capacity: 212,299 lb (96,297 kg)
Maximum Transfer Fuel Load: 207,672 lb (94,198 kg)
- Powerplant: 2 × Pratt & Whitney PW4062 turbofan, 63,300 lbf (282 kN) each
- Maximum speed: Mach 0.86 (570 mph, 914 km/h)
- Cruise speed: Mach 0.80 (530 mph, 851 km/h)
- Range: 6,385 nmi (11,830 km) ; global with in flight refueling
- Service ceiling: 40,100 ft (12,200 m)
- Related development
- Aircraft of comparable role, configuration and era
- EADS/Northrop Grumman KC-45
- Airbus A310 MRTT
- Airbus A330 MRTT
- Boeing KC-135 Stratotanker
- McDonnell Douglas KC-10 Extender
- "GAO-15-342SP DEFENSE ACQUISITIONS Assessments of Selected Weapon Programs" (PDF). US Government Accountability Office. March 2015. p. 103. Retrieved 15 July 2015.
- "Model Designation of Military Aerospace Vehicles" (PDF). US: DoD. 12 May 2004. DoD 4120.15L.
- Tirpak, John A. "100 Tankers" Archived February 26, 2011, at the Wayback Machine.. Air Force magazine, August 2003.
- "Tanker Twilight Zone", Air Force magazine, 87 (2), February 2004, archived from the original on 2011-02-26
- Pope, Charles (6 November 2003). "Pentagon finalizes Boeing tanker deal". Seattle Post-Intelligencer. Retrieved 21 July 2016.
- Cahlink, George, "Ex-Pentagon procurement executive gets jail time". Government Executive, October 1, 2004.
- Majumdar, Dave. "Boeing wins KC-X tanker battle". AirForceTimes, 24 February 2011.
- Northrop Grumman KC-30 marketing web site Archived January 30, 2009, at the Wayback Machine.
- Air Force Posts KC-X Request for Proposals Archived February 15, 2007, at the Wayback Machine.. USAF, 2007-01-30.
- Evens, Ben and Daly, Matthew (AP), "Northrop-EADS threatens to withdraw bid for US Air Force contract leaving only Boeing". Aerotech News and Review, 2 February 2007.
- Borak, D. "Boeing Unveils Air Force Tanker in $40 Billion Contract Competition". Associated Press. 12 February 2007.
- "Why the 767?" Archived April 29, 2011, at the Wayback Machine.. Air Force magazine, 13 February 2007.
- "Boeing Submits KC-767 Advanced Tanker Proposal to U.S. Air Force" Archived May 21, 2007, at the Wayback Machine.. Boeing, 11 April 2007.
- "Boeing Offers KC-767 Advanced Tanker to U.S. Air Force" Archived February 14, 2007, at the Wayback Machine.. Boeing, 12 February 2007.
- "Size matters in US Air Force KC-X contest". Flightglobal. 21 January 2008. Retrieved 25 November 2009.
- "Boeing to Offer NewGen Tanker to US Air Force" Archived July 11, 2011, at the Wayback Machine.. finchannel.com, 5 March 2010.
- "Boeing Submits Final KC-767 Advanced Tanker Proposal to U.S. Air Force" Archived June 28, 2011, at the Wayback Machine.. Boeing, 3 January 2008.
- Butler, Amy, Fulghum, Davis A and Wall, Robert. "Northrop/EADS Clinches U.S. Refueler Deal". Aviation Week, 29 February 2008.
- "GAO backs Boeing tanker protest". KING-TV. 18 June 2008. Archived from the original on December 29, 2008. Retrieved 18 June 2008.
- "Air Force to Reopen Bidding on Tanker Contract". New York Times, 10 July 2008.
- Kruzel, John J. "Pentagon Reopens Bidding on Tanker Contract" Archived August 15, 2008, at the Wayback Machine.. US DoD, 9 July 2008.
- "Pentagon Issues New Tanker Bid Parameters". Aviation Week, 6 August 2008.
- "DoD Announces Termination of KC-X Tanker Solicitation" Archived September 13, 2008, at the Wayback Machine.. US DoD, 10 September 2008.
- Air Force Resumes Tanker Contest
- "Boeing to Offer NewGen Tanker to US Air Force". Boeing, 4 March 2010.
- "EADS Re-Enters Tanker Bidding". Wall Street Journal, 21 April 2010.
- Butler, Amy. "Northrop Grumman Officially Out of KC-X"[dead link]. Aviation Week, 9 March 2010.
- Trimble, Stephen (9 July 2010). "USAF receives three proposals for KC-X, but Antonov team admits concerns". Flightglobal. Archived from the original on 13 July 2010. Retrieved 9 July 2010.
- "Boeing Submits NewGen Tanker Proposal to US Air Force". Boeing, 9 July 2010.
- Gates, Dominic. "Boeing, EADS Submit Final Bids For Air Force Tanker Contract". Seattle Times, 11 February 2011.
- "What's Next: USAF Lays Groundwork To Replace Fighter, Tanker Fleets". Defensenews.com, 14 September 2014
- Trimble, Stephen (24 February 2011). "USAF selects Boeing for KC-X contract". Washington DC: Flightglobal. Retrieved 24 February 2011.
- "Boeing Wins $35B Air Force Tanker Deal". Bloomberg, 24 February 2011.
- "Boeing Receives US Air Force Contract to Build Next-Generation Refueling Tanker" (press release). Boeing. 24 February 2011.
- Warwick, Graham. "Boeing Wins Restaged U.S. Air Force KC-X Tanker"[dead link]. Aviation Week, 25 February 2011.
- Trimble, Stephen (29 September 2010). "Boeing source reveals specifications for KC-767 NewGen Tanker". Flight International. Flightglobal. Archived from the original on 2 October 2010.
- Cappacio, Tony. "Boeing projected to face $300 million overrun on tanker contract". The Seattle Times. NW source.
- Butler, Amy (29 June 2011). "Boeing Liable For KC-46 Overage". Aviation Week. Retrieved 29 July 2011.[dead link]
- Weisgerber, Marcus. "Boeing Lowers KC-46 Cost Estimate". Defense News, 27 July 2011.
- "Air Force increases projected KC-46 flying hours, crew ratio". Global security. 2013-02-05.
- Majumdar, Dave (4 September 2013). "USAF and Boeing complete KC-46 critical design review". Washington DC: Flightglobal. Retrieved 5 September 2013.
- "US Air Force, Boeing Finalize KC-46A Tanker Aircraft Design." Boeing news release, 4 September 2013.
- "Boeing Joins First KC-46A Airframe". Aviation Week. 12 December 2013.
- "First PW4062 engines for KC-46 tanker delivered". Shephardmedia.com, 23 December 2013
- KC-46A Tanker Factsheet. U.S. Air Force, February 2016.
- "First KC-46A Baseline Test Aircraft Due This Month". DoDBuzz.com, 12 January 2014
- Hemmerdinger, Jon (16 January 2014). "Boeing assembles final KC-46A test aircraft". Washington DC: Flightglobal. Retrieved 18 January 2014.
- "KC-46 on the Money". Air Force mag. 11 April 2014.
- Cameron, Doug. "Boeing takes hit for tanker troubles"[dead link]. Wall Street Journal, 24 July 2014, p. B2.
- "Boeing Reports Second-Quarter Results and Raises 2014 EPS Guidance". Boeing, 23 July 2014.
- Trimble, Stephen (23 July 2014). "Boeing reports KC-46A loss, rejects wider concerns". Washington DC: Flightglobal. Retrieved 27 July 2014.
- Everstine, Brian (16 September 2014). "First Flight for KC-46 Tanker Platform Slips Further". Aviation Week. Penton. Retrieved 12 September 2014.
- Everstine, Brian (16 September 2014). "First flight delayed for KC-46A test aircraft". airforcetimes.com. Gannett. Archived from the original on 16 September 2014. Retrieved 16 September 2014.
- Norris, Guy (29 December 2014). "Boeing 767-2C First Flight Begins Tanker Test Campaign". Aviation Week. Retrieved 2 January 2015.
- Daryl Mayer (28 December 2014). "Boeing completes successful first flight in KC-46 program". 88th Air Base Wing Public Affairs. Retrieved 14 January 2015.
- "Supplier Quality Control, Fuel System Integration Haunt KC-46". Aviation Week. 24 July 2015. Retrieved 24 July 2015.
- "Boeing Faces Eight-Month Delay on $3 Billion Tanker Contracts". Bloomberg Business. 21 July 2015. Retrieved 21 July 2015.
- "Opinion: For Boeing, Big Losses And Missed Opportunities In The Tanker Market: KC-46 Falls Flat In International Market". Aviation Week. 22 July 2015. Retrieved 22 July 2015.
- "Boeing, U.S. Air Force Aircrews Make History with First KC-46A Tanker Refueling Flight". Boeing Press Release. 24 January 2016. Retrieved 15 February 2016.
- Thulowiet, Kenji (16 February 2016). "KC-46 refuels fighter jet with hose, drogue system for first time". USAF, 412th Test Wing Public Affairs. Retrieved 20 February 2016.
- "Boeing Likely to Miss Delivery Date for Tankers, Pentagon Says". Bloomberg. 22 March 2016. Retrieved 23 March 2016.
- Drew, James (4 April 2016). "Boeing's KC-46 test run complicated by C-17 refuelling issue". Washington DC: Flightglobal. Retrieved 5 April 2016.
- "Air Force: Boeing Tanker Issue Could Delay Production Decision". Defense News. 1 April 2016.
- Shalal, Andrea (1 April 2016). "Boeing tanker issue may delay U.S. production decision". St. Louis Post-Dispatch. Retrieved 1 April 2016.
- "Watchdog: Challenges Ahead For Boeing's KC-46 Tanker". Defense News. 11 April 2016.
- Drew, James (12 April 2016). "Boeing's 'optimistic' KC-46 plan delivers 18 tankers in six months". Washington DC: Flightglobal. Retrieved 13 April 2016.
- "Boeing Restructures To Hold The Line On 747-8". Aviation Week. 22 April 2016.
- "Fourth KC-46 test aircraft completes initial flight". IHS Jane's Defence Weekly. 27 April 2016.
- Drew, James (27 April 2016). "Boeing records $243 million KC-46 charge as it seeks LRIP contract". Washington DC: Flightglobal. Retrieved 28 April 2016.
- "Boeing KC-46 Tanker $3b Production Decision Slips to June". Bloomberg. 3 May 2016.
- Drew, James (5 May 2016). "KC-46 team working fixes to complete C-17 demo in 'late May'". Washington DC: Flightglobal. Retrieved 9 May 2016.
- "KC-46A Tanker Program Braces For Another Delay". Aviation Week. 26 May 2016.
- "Boeing's KC-46 Tanker Will Miss Major Deadline". Defense News. 27 May 2016.
- "Boeing's Penalty For Latest KC-46 Delay Still Unclear". Defense News. 2 June 2016.
- Drew, James (14 June 2016). "USAF Considering Penalty For Boeing Over KC-46 Delays". Aviation Week.
- Mehta, Aaron (12 July 2016). "Pentagon Seeks 'Consideration' for KC-46 Tanker Delay". Defense News.
- Weisgerber, Marcus (8 June 2016). "Here's How Boeing Aims To Fix Its Broken Tanker". Defense One. Atlantic Media. Retrieved 15 June 2016.
- Seligman, Lara (5 July 2016). "Boeing KC-46 Tests Moving 'Slower Than Planned'". Aviation Week.
- Mehta, Aaron (13 July 2016). "Reworked KC-46 Boom Refuels F-16, C-17". Defense News.
- Seligman, Lara (13 July 2016). "KC-46 Successfully Refuels C-17". Aviation Week.
- Erwin, Sandra (18 July 2016). "Boeing's KC-46 Tanker to Receive Production Green Light". National Defense.
- Insinna, Valerie (21 July 2016). "Boeing Racks Up Another $393M In Cost Overruns On KC-46 Program". Defense News.
- "KC-46a approved for production". U.S. Air Force. Retrieved October 10, 2016.
- On to the Stealthy KC-Z - Airforcemag.com, 21 September 2016.
- "USAF: McConnell to house next generation tankers" Archived April 24, 2014, at the Wayback Machine.. KWCH, 22 April 2014.
- "McConnell gets final OK for refueling tankers, prepares to spend $219 million for construction". The Wichita Eagle, 22 April 2014.
- "Altus selected for KC-46A training" Archived April 24, 2014, at the Wayback Machine.. Militarytimes.com, 23 April 2014.
- Secretary of the Air Force Public Affairs (29 October 2015). "Seymour-Johnson chosen for first Reserve-led KC-46A basing". Air Force Reserve Command. Archived from the original on 26 January 2016. Retrieved 14 January 2016.
- Hoyle, Craig (30 June 2014). "Boeing offers KC-46 for South Korea tanker requirement". London: Flightglobal. Retrieved 30 June 2014.
- "South Korea Selects Airbus for $1.33B Tanker Contract". Defense News. 30 June 2015. Retrieved 30 June 2015.
- Perry, Dominic (3 September 2014). "Boeing eyes Poland as first KC-46A export buyer". Warsaw: Flightglobal. Retrieved 3 September 2014.
- "Airbus leaps ahead of Boeing in race for airborne tanker exports". Puget Sound Business Journal. 24 December 2014. Retrieved 24 December 2014.
- "European Partners Opt for Airbus Military Tanker". The Wall Street Journal. 19 December 2014. Retrieved 19 December 2014.
- "新たな空中給油・輸送機の機種決定について". Ministry of Defense (Japan). 23 October 2015.
- Drew, James (23 October 2015). "Japan chooses Boeing KC-46, halting Airbus tanker winning streak". Washington DC: Flightglobal. Retrieved 24 October 2015.
- "McConnell, Pease and Altus chosen to host KC-46A tanker". Air Force Times. 2013-05-22. Archived from the original on 2014-04-30. Retrieved 2014-07-26.
- "Seymour-Johnson chosen for first Reserve-led KC-46A basing". 29 October 2015. Archived from the original on 2016-01-26. Retrieved 2016-01-14.
- KC-767 Advanced Tanker product card (archive copy), KC-767 International Tanker backgrounder. Boeing.
- 767-200ER specifications Archived February 16, 2013, at the Wayback Machine.. Boeing.
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