US Air Force Tankers: Is KC-X-Y-Z Easy As 1-2-3?
(Source:; posted Nov. 16, 2020)

(Originally published by ADIT on Nov. 13, 2020)
The US Air Force is not be able to use its new Boeing KC-46A tankers because of recurring technical and quality control problems, but the service is preparing to launch the second phase of its tanker fleet recapitalization plans. (USAF photo)
PARIS --- In spite – or because – of the KC-46’s woes, the United States Air Force is going ahead with the second step of its tanker fleet rejuvenation, known as KC-Y, according to General Jacqueline D. Van Ovost, commander of the Air Mobility Command, speaking at the at the virtual 26-29 October conference of the Airlift / Tanker Association.

The first step KC-X of the tanker fleet renewal aimed to replace part of KC-135s tanker fleet, which will be completely phased out by 2025. Initially, the Northrop Grumman/EADS (Airbus) consortium won the tender in 2008, and was awarded a $1.5 billion contract for the System Development and Demonstration (SDD) phase of the program. This phase included the manufacture of four test aircraft.

However, the program was halted when Boeing filed a protest with the Government Accountability Office (GAO). Finally, an initial $4.9 billion contract was awarded to Boeing in 2011. Out of the 179 KC-46s that the Air Force plans to purchase, 67 are already under contract and 38 have already been delivered since January 2019.

The total cost of the program (for 179 aircraft) is estimated at between $35bn and $43bn. According to some estimates, each KC-46 costs approximately $239.8mn a piece.

The second phase, KC-Y, aims to replace the the rest of the KC-135 fleet. KC-Y is supposed to be a stepping stone towards Phase 3 (KC-Z), which aims to acquire a more futuristic tanker. Van Ovost specified that the competition for Phase 2 will be "full and open". She did not give any timeline, but according to Air Force Magazine, the industry believes that if the USAF wants the KC-Y to follow production of the KC-X / KC-46 -- which is due to end in 2027 -- the financing of the bridge tanker could be included in the FY22 budget request.

Lockheed Martin expects the USAF to issue a request for information by the end of Dec. 2021, Michele A. Evans, Vice President of Lockheed Martin Aeronautics, told Air Force Magazine. An Air Mobility Command spokesman said the tanker will be a "non-development" program, meaning it will be based on an off-the-shelf, proven aircraft.


To compensate for an obvious in-flight refuelling capability shortfall, the Pentagon plans to disengage from some of its deployments currently in support of France in the framework of the Barkhane operation in Mali. In the same way, private contractor Meta Aerospace is expected to temporarily make up for the USAF's capacity shortfall.

According to General Stephen R. Lyons, the capacity shortfall is such that it already threatens the projection capacity needed to meet the expansionist ambitions of China and Russia. Finally, the Phase 2 is necessary because the ageing KC-135 fleet represents an increasingly high cost, according to General Ovost. By the time the USAF will have received its fleet of KC-46s, the remaining KC-135s will be 70 years old…

Boeing VS Airbus

As with KC-X, the two contenders for Phase 2 of the USAF's tanker renewal plan are Boeing's KC-46A and Airbus' A330 MRTT. And it is not outrageous to say that, as of today, their respective operational, financial and technical track records speak for themselves.

The KC-46 has encountered - in addition to its successive delays – numerous technical difficulties: in July 2019 a fuel leak was discovered, the Remote Vision System (RVS), developed by Rockwell Collins, is not working as expected, then another problem arose with the boom system, and the program also had to deal with recurrent Foreign Debris Contamination issues…..

These "critical failures" could take several years to correct. In 2020, the growing difficulties of the program caused Boeing's spending to almost double, increasing by $4.6bn over the initial budget ($4.9bn) - Boeing is stuck in a fixed-price contract for which it is responsible for paying all expenses beyond the initial $4.9bn awarded for the development of the aircraft.

Air Force Secretary Heather Wilson in a March 2018 interview with Bloomberg, said that "One of our frustrations with Boeing is they're much more focused on their commercial activity than on getting this right for the Air Force and getting these aircraft to the Air Force."

The many problems encountered by the KC-46 program have forced the Pentagon to delay its operational test & evaluation, which in turn will also postpone the decision to begin full production to the end of 2024 - five years behind schedule…

Why, then, did the KC-46 win the Phase 1 tender, when Boeing's tanker was just a drawing board at that time?

Firstly, the KC-46 has the advantage of being smaller, which means that more aircraft can be purchased, which gives greater flexibility for aircraft distribution on air bases with smaller ramps and runways. Secondly, if the KC-46 were chosen for Phase 2, this would allow production to continue, reducing unit costs and simplifying USAF logistics. Finally, it seems Boeing’s lobbying firepower played a major role, and might still work again….

Airbus is now well positioned in the competition to win Phase 2 and will take advantage of the difficulties of the KC-46. In Dec. 2018, Lockheed Martin and Airbus signed an MoU “to jointly explore opportunities to meet the growing demand for in-flight refuelling for US defence customers.”

Airbus would offer a variant of the A330 that would offer capabilities currently lacking in the KC-46. The A330 has the advantage of being combat-proven and operated by nine different countries (45 aircraft are already operational) whereas the KC-46 has been ordered by only two countries (Japan and Israel) in addition to the United States.

Finally, the A330 is a larger than the KC-46 aircraft which therefore meets the wishes of the USAF. If the A330 MRTT aircraft is selected, Lockheed Martin Corporation would locate the final assembly line at its Marietta (Georgia) plant.

KC-Z: A revolutionary aircraft?

While the KC-Y should be a program based on an existing aircraft, it's quite different for Phase 3, the KC-Z. "We're still undergoing basic studies on the types of attributes that this aircraft would have: Whether it's autonomous, or whether there's a pilot in it; whether it needs to be stealth-like, or just needs to be really large," Van Ovost said of the later KC-Z tanker.

As the USAF increasingly looks at the possibility of a conflict with a peer competitor over the Pacific area, the KC-Z tanker will probably be a very sophisticated, highly connected, and fully multi-mission platform. According to Colonel Tim West, deputy chief executive officer of the Air Force Research Laboratory (AFRL), the laboratory has developed and proposed an unmanned tactical tanker that could supplement the fuel requirements of high-end fighters.

Lockheed already presented futuristic, stealthy concepts, and no doubt that Boeing has other projects on its (digital) drawing board. Airbus is also expected to respond to the tender for Phase 3.

The competition between the two biggest aerospace players promises to be tough to win this military contract, and even more so with Boeing’s civil aviation business being heavily impacted by the Covid-19 pandemic.


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