The Boeing KC-46 Pegasus is an American military
aerial refueling
Aerial refueling, also referred to as air refueling, in-flight refueling (IFR), air-to-air refueling (AAR), and tanking, is the process of transferring aviation fuel from one aircraft (the tanker) to another (the receiver) while both aircraft a ...
and strategic
military transport aircraft
A military transport aircraft, military cargo aircraft or airlifter is a military aircraft, military-owned transport aircraft used to support military operations by airlifting troops and military equipment. Transport aircraft are crucial to ma ...
developed by
Boeing
The Boeing Company () is an American multinational corporation that designs, manufactures, and sells airplanes, rotorcraft, rockets, satellites, telecommunications equipment, and missiles worldwide. The company also provides leasing and product ...
from its
767 jet airliner
A jet airliner or jetliner is an airliner powered by jet engines (passenger jet aircraft). Airliners usually have two or four jet engines; three-engined designs were popular in the 1970s but are less common today. Airliners are commonly cl ...
. In February 2011, the tanker was selected by the
United States Air Force
The United States Air Force (USAF) is the air service branch of the United States Armed Forces, and is one of the eight uniformed services of the United States. Originally created on 1 August 1907, as a part of the United States Army Signal ...
(USAF) as the winner in the
KC-X tanker competition to replace older
Boeing KC-135 Stratotanker
The Boeing KC-135 Stratotanker is an American military aerial refueling aircraft that was developed from the Boeing 367-80 prototype, alongside the Boeing 707 airliner. It is the predominant variant of the C-135 Stratolifter family of transpor ...
s. The first aircraft was delivered to the Air Force in January 2019.
The Air Force intends to procure 179 Pegasus aircraft by 2027.
Development
Background
In 2001, the U.S. Air Force began 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
The United States Department of Defense (DoD, USDOD or DOD) is an executive branch department of the federal government charged with coordinating and supervising all agencies and functions of the government directly related to national secu ...
in 2002 and appeared in the 2004 edition of DoD model designation report.
The USAF decided to lease 100 KC-767 tankers from Boeing.
U.S. Senator
John McCain
John Sidney McCain III (August 29, 1936 – August 25, 2018) was an American politician and United States Navy officer who served as a United States senator from Arizona from 1987 until his death in 2018. He previously served two terms ...
and others criticized the draft leasing agreement as being wasteful and problematic. In response to protests, the USAF struck a compromise in November 2003, whereby it would purchase 80 KC-767s and lease 20 more. In December 2003, the Pentagon announced a freeze on the program over an investigation into alleged corruption that led to the jailing of
one of its former procurement executives who applied to work for Boeing. The 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 announced it may enter an even higher capability tanker based on the
Boeing 777
The Boeing 777, commonly referred to as the Triple Seven, is an American long-range wide-body airliner developed and manufactured by Boeing Commercial Airplanes. It is the world's largest twinjet.
The 777 was designed to bridge the gap bet ...
, named the ''KC-777'' Strategic Tanker.
Airbus
Airbus SE (; ; ; ) is a European Multinational corporation, multinational aerospace corporation. Airbus designs, manufactures and sells civil and military aerospace manufacturer, aerospace products worldwide and manufactures aircraft througho ...
partnered with
Northrop Grumman
Northrop Grumman Corporation is an American multinational aerospace and defense technology company. With 90,000 employees and an annual revenue in excess of $30 billion, it is one of the world's largest weapons manufacturers and military techn ...
to offer the
Airbus A330 MRTT, the tanker version of the
A330
The Airbus A330 is a wide-body aircraft developed and produced by Airbus.
Airbus conceived several derivatives of the A300, its first airliner in the mid-1970s. Then the company began development on the A330 twinjet in parallel with the A340 ...
, which was marketed to the USAF under the designation ''KC-30''. In January 2007, the USAF issued the KC-X Aerial Refueling Aircraft RFP, calling for 179 tankers (four system development and demonstration and 175 production), in a contract worth an estimated US$40 billion. However, Northrop and EADS expressed dissatisfaction at how the RFP was structured and threatened to withdraw, leaving only Boeing in the running.
[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.]
On 12 February 2007, Boeing announced it was offering the KC-767 Advanced Tanker for the KC-X,
[Borak, D]
"Boeing Unveils Air Force Tanker in $40 Billion Contract Competition"
. Associated Press
The Associated Press (AP) is an American non-profit news agency headquartered in New York City. Founded in 1846, it operates as a cooperative, unincorporated association. It produces news reports that are distributed to its members, U.S. newspa ...
. 12 February 2007. stating that the KC-767 was a better fit than the KC-777 for the requirements.
["Why the 767?"](_blank)
Air Force magazine, 13 February 2007. On 11 April 2007, Boeing submitted its KC-767 tanker proposal to USAF. The KC-767 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,
. Boeing, 12 February 2007. 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
Fly-by-wire (FBW) is a system that replaces the conventional manual flight controls of an aircraft with an electronic interface. The movements of flight controls are converted to electronic signals transmitted by wires, and flight control co ...
fuel delivery boom.
Boeing submitted its final proposal on 3 January 2008. On 29 February 2008, the DoD chose the KC-30 over the KC-767, the USAF subsequently designated it
KC-45A.
[Butler, Amy, Fulghum, Davis A and Wall, Robert]
"Northrop/EADS Clinches U.S. Refueler Deal"
''Aviation Week'', 29 February 2008. Boeing submitted a protest to the United States
Government Accountability Office
The U.S. Government Accountability Office (GAO) is a legislative branch government agency that provides auditing, evaluative, and investigative services for the United States Congress. It is the supreme audit institution of the federal govern ...
on 11 March 2008 and waged a public relations campaign in support of their protest.
On 18 June, after USAF admissions on bidding process flaws, the GAO upheld Boeing's protest and recommended the contract be rebid.
[ On 9 July 2008, ]Defense Secretary
The United States secretary of defense (SecDef) is the head of the United States Department of Defense, the executive department of the U.S. Armed Forces, and is a high ranking member of the federal cabinet. DoDD 5100.1: Enclosure 2: a The s ...
Robert Gates
Robert Michael Gates (born September 25, 1943) is an American intelligence analyst and university president who served as the 22nd United States secretary of defense from 2006 to 2011. He was originally appointed by president George W. Bush an ...
announced that the USAF would reopen bidding, and put the contract into an "expedited recompetition" with Defense Undersecretary John Young John Young may refer to:
Academics
* John Young (professor of Greek) (died 1820), Scottish professor of Greek at the University of Glasgow
* John C. Young (college president) (1803–1857), American educator, pastor, and president of Centre Col ...
in charge of the selection process, not the USAF.[Kruzel, John J]
"Pentagon Reopens Bidding on Tanker Contract"
. US DoD, 9 July 2008. A draft of the revised RFP was provided to contractors on 6 August 2008 for comments. However, on 10 September 2008, the DoD canceled the KC-X solicitation.["DoD Announces Termination of KC-X Tanker Solicitation"](_blank)
. US DoD, 10 September 2008.
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
KC-X is the United States Air Force (USAF) program to procure its next-generation aerial refueling tanker aircraft to replace some of the older Boeing KC-135 Stratotankers. The contest was for a production contract for 179 new tankers with esti ...
tanker program, the second step of the USAF's three-step tanker renewal plan, as replacing it with something entirely new is likely too big a risk. In September 2016, Air Mobility Command
Air Mobility Command (AMC) is a major command (MAJCOM) of the U.S. Air Force. It is headquartered at Scott Air Force Base, Illinois, east of St. Louis, Missouri.
Air Mobility Command was established on 1 June 1992, and was formed from elements ...
stated that the follow-on ''KC-Y'' acquisition program to replace the remaining KC-135s had been abandoned in favor of further KC-46s with upgrades.
Selection and early development
On 24 February 2011, the USAF announced the selection of Boeing's KC-767 tanker bid. The aircraft was designated ''KC-46A''. Boeing was also awarded a development contract, which called for the delivery of 18 initial operational KC-46s by 2017. The USAF sought a total of 179 new tankers. Boeing's "NewGen Tanker" is based on the 767-200 with an improved version of the KC-10
The McDonnell Douglas KC-10 Extender is an American aerial refueling tanker aircraft operated by the United States Air Force (USAF). A military version of the three-engine DC-10 airliner, the KC-10 was developed from the Advanced Tanker Cargo A ...
refueling boom
Aerial refueling, also referred to as air refueling, in-flight refueling (IFR), air-to-air refueling (AAR), and tanking, is the process of transferring aviation fuel from one aircraft (the tanker) to another (the receiver) while both aircraft a ...
, and cockpit displays from the 787.
In June 2011, development costs were reportedly 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 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 USAF completed a critical design review
In the United States military integrated acquisition lifecycle the Technical section has multiple acquisition "Technical Reviews". Technical reviews and audits assist the acquisition and the number and types are tailored to the acquisition. Over ...
(CDR) for the KC-46. With the CDR complete, the design was set and production and testing could proceed. Wing assembly for the first aircraft began on 26 June 2013. Flight testing of the 767-2C airframe, which would be reconfigured into the KC-46, was scheduled to begin in mid-2014. The first fully-equipped KC-46 was projected to fly in early 2015. The contract called for Boeing to build four test aircraft and deliver 18 combat-ready tankers by August 2017. The USAF 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. 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 was to be integrated with the needed systems and technologies to become a military-standard KC-46A by January 2015. Seven low-rate production KC-46s were to be delivered in 2015, 12 in 2016, and 15 delivered annually from 2017 to 2027.["First KC-46A Baseline Test Aircraft Due This Month"](_blank)
. DoDBuzz.com, 12 January 2014 The last of four test aircraft began assembly on 16 January 2014.
In April 2014, the Government Accountability Office
The U.S. Government Accountability Office (GAO) is a legislative branch government agency that provides auditing, evaluative, and investigative services for the United States Congress. It is the supreme audit institution of the federal govern ...
(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 USAF estimated the development program's cost, 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 the tanker's wiring redesign. 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 a USAF 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.
Flight tests and delays
The 767-2C's first flight took place on 28 December 2014; it flew from Paine Field
Paine Field , also known as Snohomish County Airport, is a commercial and general aviation airport serving the Seattle metropolitan area in the U.S. state of Washington. It is located in unincorporated Snohomish County, Washington, between the ...
and landed at Boeing Field
Boeing Field, officially King County International Airport , is a public airport owned and operated by King County, five miles south of downtown Seattle, Washington. The airport is sometimes referred to as KCIA (King County International Airpo ...
. In March 2015, a refueling test with a C-17 transport was stopped because of a higher-than-expected boom axial load while delivering fuel; the problem was caused by the turbulent "bow wave effect" generated by two large aircraft flying in line. On 24 January 2016, the KC-46 successfully refueled an F-16
The General Dynamics F-16 Fighting Falcon is a single-engine Multirole combat aircraft, multirole fighter aircraft originally developed by General Dynamics for the United States Air Force (USAF). Designed as an air superiority day fighter, it ...
for the first time during a 5 hour 36 minute sortie. Test refueling of several other military aircraft followed, including a C-17, F/A-18
The McDonnell Douglas F/A-18 Hornet is an all-weather, twin-engine, supersonic, carrier-capable, multirole combat aircraft, designed as both a fighter and attack aircraft (hence the F/A designation). Designed by McDonnell Douglas (now part ...
, A-10
The Fairchild Republic A-10 Thunderbolt II is a single-seat, twin-turbofan, straight-wing, subsonic attack aircraft developed by Fairchild Republic for the United States Air Force (USAF). In service since 1976, it is named for the Republi ...
, and AV-8B
The McDonnell Douglas (now Boeing) AV-8B Harrier II is a single-engine ground-attack aircraft that constitutes the second generation of the Harrier family, capable of vertical or short takeoff and landing (V/STOL). The aircraft is primaril ...
. On 10 February, a KC-46 refueled an F/A-18, using its probe-and-drogue system for the first time.
In July 2015, Boeing announced a further $835 million pretax charge for the faulty integrated fuel system's redesign and retrofit. Wiring and fuel system flaws could delay contracts worth $3 billion for up to eight months; following schedule revisions agreed by the USAF and Boeing, the first flight of a fully equipped KC-46 was delayed to as late as September 2015. 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 22 March 2016, the Defense Contract Management Agency
The Defense Contract Management Agency (DCMA) is an agency of the United States federal government reporting to the Under Secretary of Defense for Acquisition and Sustainment. It is responsible for administering contracts for the United States D ...
reportedly had low confidence in the August 2017 deadline, predicting the first 18 tankers' delivery to run about seven months late based on past performance and current risks, such as production delays, a new joint USAF-Boeing schedule review, and flight test uncertainties. The Pentagon's test office was to start combat testing in April 2017.
An April 2016 GAO report projected an additional four months beyond the August 2017 target to deliver 18 KC-46s, and that operational testing will not begin until May 2017 and will not be completed until two months after delivery of the first 18 aircraft, risking late discoveries of problems. The GAO also noted that Boeing has not obtained Federal Aviation Administration
The Federal Aviation Administration (FAA) is the largest transportation agency of the U.S. government and regulates all aspects of civil aviation in the country as well as over surrounding international waters. Its powers include air traffic m ...
'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 projected readiness for FAA certification by July 2017, over three years late. The 18 KC-46s were to include the four EMD aircraft raised to operational standards, plus the first 14 low-rate production tankers. Instead, 16 of the 18 were off the production line; Boeing was also liable for all late design fixes on tankers delivered before testing ended.
On 25 April 2016, the fourth test aircraft, 767-2C EMD-3, first flew. EMD-3 focused on environmental control systems, including temperature and smoke penetration testing. Two days later, Boeing took another pre-tax charge of $243 million for cost overruns, bringing the total amount paid for tanker cost overruns to $1.5 billion. Boeing president and chief executive Dennis Muilenburg
Dennis A. Muilenburg (born 1964) is an American engineer, business executive, and the former president and chief executive officer (CEO) of The Boeing Company, a multinational aerospace and defense company. He was CEO from 2015 to 2019, when h ...
stated that 80% of the test points required for a positive Milestone C decision had been completed. Flight testing helped determine whether a refueling fault could be resolved by either software or hardware changes, which Boeing worked on in parallel.
On 26 May 2016, a further delay of at least six months due to technical and supply chain issues was reported, potentially requiring program re-structuring and cuts. At the time, only 20% of the flight tests were completed. On 2 June 2016, USAF spokesman Maj. Rob Leese confirmed that, while the contract with Boeing lacked predefined delay penalties, not delivering the 18 certified KC-46s by August 2017 is a contract schedule breach, and that the USAF would receive considerations from Boeing in the schedule re-baseline after the RRA delay. On 12 July 2016, US Defense Acquisitions Chief Frank Kendall confirmed that the tanker program office was studying the delay's cost to the USAF, and that it was entitled to consideration for losses from operating the KC-135 for longer than planned.
On 8 June 2016, Boeing's defense unit CEO, Leanne Caret
Leanne Caret (born 18 November 1966) is an American businesswoman, former president and CEO of Boeing Defense, Space & Security (BDS), former executive vice president of Boeing, and serves on the United Service Organizations (USO) board of gover ...
, reported that a modified boom would be flown shortly. On 10 July 2016, Caret reported positive results from early flight tests with the revised boom. On 21 July 2016, Boeing took a further $393 million charge on the program, bringing the total value of penalties to almost $1.9 billion. The charge reflected higher costs associated with the schedule and technical challenges, such as the boom axial load issue, delays in the certification process and concurrency between testing and initial production. The initial 18 KC-46s were equipped with the boom and centerline drogue, but not the wing-mounted wing-aerial refueling pods (WARP) needed for full contractual Required Assets Available, they were delivered separately later.
On 5 July 2016, USAF spokesman Daryl Mayer stated that, despite the testing delays, Milestone C approval was expected in the following month, and that Boeing would add a fifth EMD aircraft to accelerate testing. EMD-1 and EMD-3 primarily conducted flight tests towards FAA airworthiness certificates, while EMD-2 and EMD-4 focused on USAF aerial refueling and 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 underwent regression testing on the F-16, followed by refueling demonstrations with the C-17 and A-10 for the final test for Milestone C approval. On 15 July 2016, the KC-46 successfully refueled an A-10, offloading 1,500 pounds of fuel at 15,000 feet. At the time, more than 900 flight test hours have been completed by the five EMD aircraft. On 12 August 2016, the program received Milestone C approval, indicating production readiness; the issuing of contracts for two lots covering 19 aircraft was expected within 30 days.
In January 2018, Air Mobility Command stated that tests for final FAA certification were roughly 94 percent complete. Boeing announced its FAA certification on 4 September 2018, with military certification outstanding. Aircraft refueled during testing include the F-16, F/A-18, AV-8B, C-17, A-10, KC-10
The McDonnell Douglas KC-10 Extender is an American aerial refueling tanker aircraft operated by the United States Air Force (USAF). A military version of the three-engine DC-10 airliner, the KC-10 was developed from the Advanced Tanker Cargo A ...
, KC-135
The Boeing KC-135 Stratotanker is an American military aerial refueling aircraft that was developed from the Boeing 367-80 prototype, alongside the Boeing 707 airliner. It is the predominant variant of the C-135 Stratolifter family of transpo ...
and the KC-46 itself. On 22 January 2019, a KC-46 from the 418th Flight Test Squadron
The 418th Flight Test Squadron is a United States Air Force squadron. It is assigned to the 412th Operations Group, Air Force Materiel Command, stationed at Edwards Air Force Base, California.
The first predecessor of the squadron was acti ...
at Edwards AFB
Edwards Air Force Base (AFB) is a United States Air Force installation in California. Most of the base sits in Kern County, but its eastern end is in San Bernardino County and a southern arm is in Los Angeles County. The hub of the base is Ed ...
made connection with an F-35A
The Lockheed Martin F-35 Lightning II is an American family of single-seat, single-engine, all-weather stealth multirole combat aircraft that is intended to perform both air superiority
Aerial supremacy (also air superiority) is the ...
, the occasion being the first time that the KC-46 connected with a fifth-generation jet fighter
A fifth-generation fighter is a jet fighter aircraft classification which includes major technologies developed during the first part of the 21st century. , these are the most advanced fighters in operation. The characteristics of a fifth-gene ...
. Completion of refueling certification of the F-35 by the KC-46 was announced by the 412th Test Wing on 5 June 2019.
On 30 March 2020, the USAF announced that chronic leaks in the fuel system had been upgraded to a Category I deficiency. The USAF identified the issue in June 2019, but had not originally believed it to be serious. Crews became aware of the issue when they discovered fuel between the primary and secondary fuel protection barriers; there was no known root cause at the time of the announcement. By January 2021, Boeing's losses on the program were estimated at $5 billion.[Reim, Garrett]
"Boeing delivers 14 KC-46A tankers in 2020, receives contract for a dozen more"
Flight Global
FlightGlobal is an online news and information website which covers the aviation and aerospace industries.
The website was established in February 2006 as the website of ''Flight International'' magazine, ''Airline Business'', ''ACAS'', ''Air ...
, 13 January 2021. At the time, it was expected that the KC-46 would not be combat ready until at least late 2023.
Design
The KC-46 Pegasus is a variant of the Boeing 767
The Boeing 767 is an American wide-body aircraft developed and manufactured by Boeing Commercial Airplanes.
The aircraft was launched as the 7X7 program on July 14, 1978, the prototype first flew on September 26, 1981, and it was certified on ...
and is a widebody, low-wing cantilever monoplane with a conventional empennage
The empennage ( or ), also known as the tail or tail assembly, is a structure at the rear of an aircraft that provides stability during flight, in a way similar to the feathers on an arrow.Crane, Dale: ''Dictionary of Aeronautical Terms, third ed ...
featuring a single fin and rudder. It has a retractable tricycle landing gear
Tricycle gear is a type of aircraft undercarriage, or ''landing gear'', arranged in a tricycle fashion. The tricycle arrangement has a single nose wheel in the front, and two or more main wheels slightly aft of the center of gravity. Tricycle g ...
and a hydraulic flight control system. The Pegasus is powered by two Pratt & Whitney PW4062 engines, one mounted under each wing. It has been described as combining "the 767-200ER's fuselage, with the 767-300F's wing, gear, cargo door and floor, with the 767-400ER digital flightdeck and flaps". The KC-46 uses a similar Maneuvering Characteristics Augmentation System
The Maneuvering Characteristics Augmentation System (MCAS) is a flight stabilizing feature developed by Boeing that became notorious for its role in two fatal accidents of the 737 MAX, which killed all 346 passengers and crew among both flights ...
(MCAS) to that implicated in two 737 MAX crashes; in March 2019, the USAF began reviewing KC-46 training due to this feature. Unlike the 737, the KC-46's MCAS takes input from dual redundant angle of attack sensors and disengages with stick input by the pilot.
The flightdeck has room for a crew of four with a forward crew compartment with seats for 15 crew members and in the rear fuselage either palletized passenger seating for 58, or 18 pallets in cargo configuration. The rear compartment can also be used in an aero-medical configuration for 54 patients (24 on litters). The KC-46A can carry of fuel,[ 10 percent more than the KC-135, and of cargo. Survivability is improved with ]infrared countermeasures
An infrared countermeasure (IRCM) is a device designed to protect aircraft from infrared homing ("heat seeking") missiles by confusing the missiles' infrared guidance system so that they miss their target (electronic countermeasure). Heat-see ...
and the aircraft has limited electronic warfare
Electronic warfare (EW) is any action involving the use of the electromagnetic spectrum (EM spectrum) or directed energy to control the spectrum, attack an enemy, or impede enemy assaults. The purpose of electronic warfare is to deny the opponen ...
capabilities. It uses manual flight controls, allowing unrestricted maneuverability to avoid threats anywhere in the flight envelope
In aerodynamics, the flight envelope, service envelope, or performance envelope of an aircraft or spacecraft refers to the capabilities of a design in terms of airspeed and load factor or atmospheric density, often simplified to altitude. The t ...
.
At the rear of the aircraft is a fly-by-wire refueling boom supplemented by wing air refueling pods at each wingtip and a centerline drogue system under the rear fuselage so it can handle both types of refueling in one mission.
Rather than using a single boom operator seated or prone at the tail looking out a window, the Aerial Refueling Operator Station (AROS) seats two operators at a video station at the front of the aircraft. They view images from a series of multi-spectral cameras distributed around the aircraft. AROS includes three main displays in front of each operator. The central 2D/3D display provides a view out the back of the aircraft for boom refueling operations. Boom operators can execute their mission in total darkness, with both aircraft blacked out. The hybrid 2D-3D system requires the use of stereoscopic glasses to get the full effect. The Remote Vision System (RVS) that feeds video to the AROS has been a source of problems including motion viewed in the RVS versus which can create a depth compression and curvature effect.
Blackouts and washouts on the video displays during refueling, caused by shadows or direct sunlight are a problem that will be fixed by the RVS 2.0 upgrade. RVS 2.0 is expected to alleviate problems in depth perception with new cameras and a full-color, high-definition screen. Boom operators with hundreds of hours of experience on older refuelers still prefer the KC-46, even with its current drawbacks.
The boom is furnished with a hydraulic relief valve system, similar to those on the KC-10 and KC-767 tankers, to relieve axial pressure in the event of excessive loads building up on the boom. Near the front landing gear, there is a ladder that can be pulled down, providing quick ingress by the crew to the aircraft.
Operational history
United States
On 23 April 2014, the USAF announced that the KC-46 will be based at McConnell Air Force Base
McConnell Air Force Base is a United States Air Force base located four miles (6 km) southeast of the central business district of Wichita, a city in Sedgwick County, Kansas, United States., effective 2007-12-20 The airbase was named in ...
in Wichita, Kansas
Wichita ( ) is the largest city in the U.S. state of Kansas and the county seat of Sedgwick County, Kansas, Sedgwick County. As of the 2020 United States census, 2020 census, the population of the city was 397,532. The Wichita metro area had ...
, with an optimistic expectation of receiving the first of 36 tankers in 2016. McConnell AFB was chosen because it had low construction costs and it is in a location with a high demand for air refueling, having KC-135 Stratotankers based there. In addition to McConnell AFB serving as the home base, up to 10 operating bases will be used by the KC-46. Crews will be trained at Altus Air Force Base
Altus Air Force Base (Altus AFB, AAFB) is a United States Air Force base located approximately east-northeast of Altus, Oklahoma.
The host unit at Altus AFB is the 97th Air Mobility Wing (97 AMW), assigned to the Nineteenth Air Force (19 AF ...
, Oklahoma, which was also chosen for its limited construction needs and for its existing experience with training programs for the C-17 Globemaster
The McDonnell Douglas/Boeing C-17 Globemaster III is a large military transport aircraft that was developed for the United States Air Force (USAF) from the 1980s to the early 1990s by McDonnell Douglas. The C-17 carries forward the name of two ...
and the KC-135.
On 29 October 2015, the USAF announced that Seymour Johnson Air Force Base
Seymour Johnson Air Force Base is a United States Air Force (USAF) base located in Goldsboro, North Carolina. The base is named for U.S. Navy Lt. Seymour A. Johnson, a test pilot from Goldsboro who died in an airplane crash near Norbeck, Maryland, ...
, North Carolina, was chosen as the preferred alternative for the first Reserve-led KC-46A main operating base, with an anticipated arrival of the KC-46As at Seymour Johnson in fiscal year 2019. Tinker Air Force Base
Tinker Air Force Base is a major United States Air Force base, with tenant U.S. Navy and other Department of Defense missions, located in Oklahoma County, Oklahoma, surrounded by Del City, Oklahoma City, and Midwest City.
The base, origina ...
, Oklahoma; Westover Air Reserve Base
Westover Air Reserve Base is an Air Force Reserve Command (AFRC) installation located in the Massachusetts communities of Chicopee and Ludlow, near the city of Springfield, Massachusetts. Established at the outset of World War II, today Westo ...
, Massachusetts; and Grissom Air Reserve Base
Grissom Air Reserve Base is a United States Air Force base, located about north of Kokomo in Cass and Miami counties in Indiana. The facility was established as a U.S. Navy installation, Naval Air Station Bunker Hill, in 1942 and was an active ...
, Indiana, were named as the reasonable alternatives. The October 2015 announcement also stated that the USAF intended to initiate an Environmental Impact Analysis Process (EIAP), which the USAF would use to make its final basing decisions.
On 10 January 2019, the USAF took delivery of the first KC-46, well past the original 2016 delivery date, albeit with two issues outstanding and funds withheld. The two outstanding issues were inadequate boom pressure when refueling the A-10 Warthog
The Fairchild Republic A-10 Thunderbolt II is a single-seat, twin-turbofan, straight-wing, subsonic attack aircraft developed by Fairchild Republic for the United States Air Force (USAF). In service since 1976, it is named for the Republic ...
and glare induced distortion under certain conditions in the remote vision system (RVS). The USAF acknowledged that they failed to give Boeing adequate specifications for the A-10. At milestone C, Boeing gave the USAF a boom design that used the international standard of 1400 lbs of thrust resistance, which they accepted, but A-10 is only able to generate 650 lbs.
On 25 January 2019, the 22d Air Refueling Wing at McConnell AFB received its first two KC-46As (''15-46009'' and ''17-46031''). On 3 February 2019, the 97th Air Mobility Wing
The 97th Air Mobility Wing (97 AMW) is a United States Air Force (USAF) unit assigned to Nineteenth Air Force of Air Education and Training Command. It is stationed at Altus Air Force Base, Oklahoma. The wing is also the host unit at Altus. I ...
at Altus AFB received its first KC-46.
On 2 April 2019, it was confirmed that the USAF halted all deliveries on 23 March and until further notification, as loose material and debris were found in planes already delivered.
On 8 August 2019, the 157th Air Refueling Wing at Pease Air National Guard Base
Pease Air National Guard Base is a New Hampshire Air National Guard base located at Portsmouth International Airport at Pease in New Hampshire. It occupies a portion of what was once Pease Air Force Base, a former Strategic Air Command facility ...
received its first KC-46A.
On 12 September 2019, the USAF restricted the KC-46 from carrying cargo and passengers due to an issue with the floor cargo locks unlocking mid-flight. A fix was approved by the USAF on 12 November 2019 and were retrofitted upon delivered aircraft. By 20 December 2019, four KC-46As had received new cargo locks and the USAF had closed the Category 1 deficiency and cleared retrofitted aircraft for cargo and passenger operations.
On 12 June 2020, the 916th Air Refueling Wing
The 916th Air Refueling Wing is an Air Reserve Component (ARC) of the United States Air Force. It is assigned to the Fourth Air Force, Air Force Reserve Command, stationed at Seymour Johnson Air Force Base, North Carolina. If mobilized, the W ...
at Seymour Johnson Air Force Base
Seymour Johnson Air Force Base is a United States Air Force (USAF) base located in Goldsboro, North Carolina. The base is named for U.S. Navy Lt. Seymour A. Johnson, a test pilot from Goldsboro who died in an airplane crash near Norbeck, Maryland, ...
received its first KC-46A. By January 2021, Boeing had delivered 42 KC-46As to the USAF and was on contract for 94 tankers.[Reim, Garrett]
''Boeing wins $2.1bn for 15 more KC-46A tankers, points to battle communications role''
Flight Global
FlightGlobal is an online news and information website which covers the aviation and aerospace industries.
The website was established in February 2006 as the website of ''Flight International'' magazine, ''Airline Business'', ''ACAS'', ''Air ...
, 22 January 2021.
In early 2021, the USAF cleared the KC-46 for limited operational use, years after its planned 2017 introduction. The type can conduct U.S.-based refueling only, requiring other tankers for deployments to combat areas. At the time, the KC-46 could refuel the B-52, F-15, F-16, and F/A-18, but it was not approved to service the A-10, F-22, F-35, B-1, or B-2; it is expected to be fully combat-ready by 2023.[Despite growing pains, KC-46 tanker will begin 'limited operations']
''Defense News
''Defense News'' is a website and newspaper about the politics, business, and technology of national security published by Sightline Media Group. Founded in 1986, ''Defense News'' serves an audience of senior military, government, and industry de ...
''. 25 February 2021.
As of 14 September 2022, the USAF approved the KC-46 for general operational use, closing out a 15-month evaluation period.
Export bids
India
In January 2018, the Indian Air Force
The Indian Air Force (IAF) is the air arm of the Indian Armed Forces. Its complement of personnel and aircraft assets ranks third amongst the air forces of the world. Its primary mission is to secure Indian airspace and to conduct aerial w ...
re-launched its air-to-air refueling procurement program, and sent out a request for information for six refueling aircraft to Airbus, Boeing
The Boeing Company () is an American multinational corporation that designs, manufactures, and sells airplanes, rotorcraft, rockets, satellites, telecommunications equipment, and missiles worldwide. The company also provides leasing and product ...
, and Ilyushin
The public joint stock company Ilyushin Aviation Complex, operating as Ilyushin (russian: Илью́шин) or as Ilyushin Design Bureau, is a former Soviet and now a Russian aircraft manufacturer and design bureau, founded in 1933 by Sergey Vl ...
, to which Boeing could respond with an offer for the KC-46 Pegasus. Airbus and Boeing responded to the request for information, while Ilyushin was disqualified as the official requirement is for an aircraft with two turbofan
The turbofan or fanjet is a type of airbreathing jet engine that is widely used in aircraft engine, aircraft propulsion. The word "turbofan" is a portmanteau of "turbine" and "fan": the ''turbo'' portion refers to a gas turbine engine which ac ...
engines.
On 6 April 2022, Hindustan Aeronautics Limited (HAL) announced that it had entered into an MoU with Israel Aerospace Industries (IAI) to convert passenger aircraft into multi-mission tanker transport (MMTT) aircraft in India.
Indonesia
In January 2018, Indonesian Air Force
The Indonesian Air Force ( id, Tentara Nasional Indonesia Angkatan Udara (TNI-AU), literally "''Indonesian National Military-Air Force''") sometimes shortened as IDAF / IdAF, is the aerial branch of the Indonesian National Armed Forces. The ...
officials were reported as saying they were studying both the Airbus A330 MRTT and Boeing KC-46 Pegasus aerial refueling aircraft for a future modernization program, expected to take place after the current Airbus A400M Atlas
The Airbus A400M AtlasNamed after the Greek mythological figure. is a European four-engine turboprop military transport aircraft. It was designed by Airbus Military (now Airbus Defence and Space) as a tactical airlifter with strategic capab ...
program completes. The Indonesian Air Force is said to compare the aircraft on compatibility with the force's current aircraft, life-cycle costs, interoperability with current and future assets, and potential funding and technology transfer options with state-owned aircraft manufacturer Indonesian Aerospace
Indonesian Aerospace (IAe) ( id, PT Dirgantara Indonesia (Persero)), is an Indonesian aerospace company involved in aircraft design and the development and manufacture of civilian and military regional commuter aircraft. The company was formerly k ...
.
Japan
The Japan Air Self-Defense Force
The , , also informally referred to as the Japanese Air Force, is the air and space branch of the Japan Self-Defense Forces, responsible for the defense of Japanese airspace, other air and space operations, cyberwarfare and electronic warfa ...
(JASDF) operates four of the earlier Boeing KC-767 tankers that were delivered from 2008 to 2010. On 23 October 2015, Japan selected the KC-46, 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
The Bell Boeing V-22 Osprey is an American multi-mission, tiltrotor military aircraft with both vertical takeoff and landing (VTOL) and short takeoff and landing (STOL) capabilities. It is designed to combine the functionality of a convention ...
tiltrotor
A tiltrotor is an aircraft which generates lift and propulsion by way of one or more powered rotors (sometimes called ''proprotors'') mounted on rotating shafts or nacelles usually at the ends of a fixed wing. Almost all tiltrotors use a trans ...
s, which the JASDF is to receive. Airbus declined to bid its 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. An order for a third and fourth KC-46 was placed on 30 October 2020. Japan has ordered two additional KC-46 tankers in December 2022 for the Japan Air Self-Defense Force (JASDF), bringing Japan's order total to six.
On 8 February 2021, the JASDF conducted its first KC-46 flight. Training of Japanese KC-46 pilots began in June 2021 and Japan received its first KC-46 in November 2021.
Israel
On 3 March 2020, the State Department
The United States Department of State (DOS), or State Department, is an United States federal executive departments, executive department of the Federal government of the United States, U.S. federal government responsible for the country's fore ...
approved the Foreign Military Sale to Israel
Israel (; he, יִשְׂרָאֵל, ; ar, إِسْرَائِيل, ), officially the State of Israel ( he, מְדִינַת יִשְׂרָאֵל, label=none, translit=Medīnat Yīsrāʾēl; ), is a country in Western Asia. It is situated ...
of eight KC-46s and related equipment for a cost of $2.4 billion.
On 1 September 2022, Boeing announced Israel has purchased four KC-46A aircraft from the company to be delivered in 2025.
Others
In May 2019, according to manufacturer Boeing, the United Arab Emirates
The United Arab Emirates (UAE; ar, اَلْإِمَارَات الْعَرَبِيَة الْمُتَحِدَة ), or simply the Emirates ( ar, الِْإمَارَات ), is a country in Western Asia (The Middle East). It is located at th ...
made a formal request to procure three KC-46As.
Failed bids
Canada
On 2 February 2017, Boeing stated it would bid the KC-46A for the Royal Canadian Air Force
The Royal Canadian Air Force (RCAF; french: Aviation royale canadienne, ARC) is the air and space force of Canada. Its role is to "provide the Canadian Forces with relevant, responsive and effective airpower". The RCAF is one of three environm ...
's Strategic Tanker Transport Capability competition, which is to replace Canada's fleet of CC-150 Polaris tankers. The contract is valued at C$1.5+ billion. However, on 1 April 2021, Airbus Defence and Space
Airbus Defence and Space is the division of Airbus SE responsible for the development and manufacturing of the corporation's defence and space products, while also providing related services. The division was formed in January 2014 during the ...
and their submission of the A330 MRTT
The Airbus A330 Multi Role Tanker Transport (MRTT) is a European aerial refuelling and military transport aircraft based on the civilian Airbus A330. A total of 16 countries have placed firm orders for approximately 68 aircraft, of which 51 ha ...
was deemed to be the only qualified bidder to replace the CC-150.
Korea
In June 2014, Boeing submitted the KC-46 for the Republic of Korea Air Force
The Republic of Korea Air Force (ROKAF; ko, 대한민국 공군; RR: ''Daehanminguk Gong-gun''), also known as the ROK Air Force or South Korean Air Force, is the aerial warfare service branch of South Korea, operating under the Ministry of N ...
's requirement for four aerial tankers. The KC-46 competed with the Airbus A330 MRTT; South Korea selected the Airbus A330 MRTT in June 2015.
Poland
Boeing pitched the KC-46 to the Polish Air Force
The Polish Air Force ( pl, Siły Powietrzne, , Air Forces) is the aerial warfare branch of the Polish Armed Forces. Until July 2004 it was officially known as ''Wojska Lotnicze i Obrony Powietrznej'' (). In 2014 it consisted of roughly 16,425 mil ...
for its tanker requirement. In December 2014, Airbus was awarded a contract for four A330 MRTTs from a consortium of Poland, the Netherlands, and Norway.
Operators
;
*Israeli Air Force
The Israeli Air Force (IAF; he, זְרוֹעַ הָאֲוִיר וְהֶחָלָל, Zroa HaAvir VeHahalal, tl, "Air and Space Arm", commonly known as , ''Kheil HaAvir'', "Air Corps") operates as the aerial warfare branch of the Israel Defense ...
- 4 aircraft on order, out of 8 planned
;
*Japan Air Self-Defense Force
The , , also informally referred to as the Japanese Air Force, is the air and space branch of the Japan Self-Defense Forces, responsible for the defense of Japanese airspace, other air and space operations, cyberwarfare and electronic warfa ...
- 2nd of 4 aircraft on order delivered as of 24 February 2022
;
*United States Air Force
The United States Air Force (USAF) is the air service branch of the United States Armed Forces, and is one of the eight uniformed services of the United States. Originally created on 1 August 1907, as a part of the United States Army Signal ...
- 61 aircraft delivered
** 412th Test Wing (AFMC) - Edwards AFB
Edwards Air Force Base (AFB) is a United States Air Force installation in California. Most of the base sits in Kern County, but its eastern end is in San Bernardino County and a southern arm is in Los Angeles County. The hub of the base is Ed ...
, California
California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...
(2 on loan from McConnell AFB)
***418th Flight Test Squadron
The 418th Flight Test Squadron is a United States Air Force squadron. It is assigned to the 412th Operations Group, Air Force Materiel Command, stationed at Edwards Air Force Base, California.
The first predecessor of the squadron was acti ...
**97th Air Mobility Wing
The 97th Air Mobility Wing (97 AMW) is a United States Air Force (USAF) unit assigned to Nineteenth Air Force of Air Education and Training Command. It is stationed at Altus Air Force Base, Oklahoma. The wing is also the host unit at Altus. I ...
(AETC) – Altus AFB
Altus Air Force Base (Altus AFB, AAFB) is a United States Air Force base located approximately east-northeast of Altus, Oklahoma.
The host unit at Altus AFB is the 97th Air Mobility Wing (97 AMW), assigned to the Nineteenth Air Force (19 A ...
, Oklahoma
Oklahoma (; Choctaw language, Choctaw: ; chr, ᎣᎧᎳᎰᎹ, ''Okalahoma'' ) is a U.S. state, state in the South Central United States, South Central region of the United States, bordered by Texas on the south and west, Kansas on the nor ...
(aircrew training), full complement of 8 delivered as of 6 October 2021
*** 56th Air Refueling Squadron
** 22d Air Refueling Wing (AMC) – McConnell AFB, Kansas
Kansas () is a state in the Midwestern United States. Its capital is Topeka, and its largest city is Wichita. Kansas is a landlocked state bordered by Nebraska to the north; Missouri to the east; Oklahoma to the south; and Colorado to the ...
, 22 delivered as of 20 May 2022
*** 344th Air Refueling Squadron
** 157th Air Refueling Wing (ANG) – Pease ANGB, New Hampshire
New Hampshire is a U.S. state, state in the New England region of the northeastern United States. It is bordered by Massachusetts to the south, Vermont to the west, Maine and the Gulf of Maine to the east, and the Canadian province of Quebec t ...
, full complement of 12 delivered as of 5 February 2021
*** 133d Air Refueling Squadron
**916th Air Refueling Wing
The 916th Air Refueling Wing is an Air Reserve Component (ARC) of the United States Air Force. It is assigned to the Fourth Air Force, Air Force Reserve Command, stationed at Seymour Johnson Air Force Base, North Carolina. If mobilized, the W ...
(AFRC) – Seymour Johnson AFB
Seymour Johnson Air Force Base is a United States Air Force (USAF) base located in Goldsboro, North Carolina. The base is named for U.S. Navy Lt. Seymour A. Johnson, a test pilot from Goldsboro who died in an airplane crash near Norbeck, Maryland, ...
, North Carolina
North Carolina () is a state in the Southeastern region of the United States. The state is the 28th largest and 9th-most populous of the United States. It is bordered by Virginia to the north, the Atlantic Ocean to the east, Georgia and So ...
, 11 delivered as of 3 June 2022
*** 77th Air Refueling Squadron
**6th Air Mobility Wing
The United States Air Force's 6th Air Refueling Wing is the host wing for MacDill Air Force Base, Florida. It is part of Air Mobility Command's (AMC) Eighteenth Air Force. The wing's 6th Operations Group is a successor organization of the 3d Ob ...
(AMC)
*** 911th Air Refueling Squadron – Seymour Johnson AFB
Seymour Johnson Air Force Base is a United States Air Force (USAF) base located in Goldsboro, North Carolina. The base is named for U.S. Navy Lt. Seymour A. Johnson, a test pilot from Goldsboro who died in an airplane crash near Norbeck, Maryland, ...
, North Carolina
North Carolina () is a state in the Southeastern region of the United States. The state is the 28th largest and 9th-most populous of the United States. It is bordered by Virginia to the north, the Atlantic Ocean to the east, Georgia and So ...
(Active Duty Associate to the 916 ARW)
**305th Air Mobility Wing
The 305th Air Mobility Wing is a United States Air Force strategic airlift and air refueling wing under the operational control of the Air Mobility Command. It generates, mobilizes and deploys C-17 Globemaster III and KC-10 Extender aircraft. ...
(AMC) - Joint Base McGuire–Dix–Lakehurst
Joint Base McGuire–Dix–Lakehurst (JB MDL) is a United States military facility located southeast of Trenton, New Jersey. The base is the only tri-service base in the United States Department of Defense and includes units from all six armed ...
, 8 of 24 delivered as of 17 June 2022
*** 2nd Air Refueling Squadron
** 514th Air Mobility Wing (AFRC) - Joint Base McGuire–Dix–Lakehurst
Specifications
See also
References
External links
*
Boeing.com Feature story on KC-46A contract award
*
{{US transport aircraft
KC-46
Twinjets
Air refueling
Boeing 767
Low-wing aircraft
Aircraft first flown in 2015