Pontifications: Think tank analyzes KC-Y competitive landscape

Nov. 29, 2021, © Leeham News: A conservative think tank believes the US Air Force must invest not only in another round of aerial refueling tankers. It must also invest in infrastructure and future, innovative designs.

By Scott Hamilton

The Hudson Institute in Washington (DC) issued a study earlier this month in which it analyzed the Air Force’s global refueling requirements. The study may be downloaded here.

While perusing the website and looking at who’s involved with the institute makes it clear this isn’t just a conservative think tank but an overtly partisan one as well, the study appears well thought out and even-handed. It relies on well-reasoned data. The study is unlike Loren Thompson of the Lexington Institute, whose latest column about the next round of tanker procurement returns to the tiresome and expired whining about illegal subsidies for the Airbus A330-200.

Breaking news to Loren: the WTO case is over. Additional breaking news: subsidies and the WTO aren’t considered in military procurements. The Lexington Institute gets funding from Boeing. It also previously received funding from Lockheed. Thompson did not disclose in this latest missive if it still does.

Looking at the KC-Y procurement

Hudson received funding from Lockheed in 2020, the most recent information available on its contributors. But the authors say Lockheed had no role in creating this study.

Hudson’s study, by Timothy Walton and Bryan Clark, suggests that the Air Force’s requirements for “surface architecture” are so great that money should be invested even at the expense of purchasing some tankers in the KC-Y round.

KC-Y was intended to be a replacement for the aging McDonnell Douglas KC-10s. But this is now called a bridge tanker program. The Air Force intends to purchase between 140-160 more tankers to replace more ancient KC-135 tankers. KC-X, the first round, is a contract to buy 179 tankers. After three efforts, two of which were marred by scandal, Boeing won the contract for what was named the KC-46A based on the passenger 767-200ER model.

KC-Y competition is going to be between Boeing’s KC-46A and a revised version of the A330-200 Multi-Role Tanker Transport. Airbus joined with Lockheed Martin, which will be the lead in the new competition. Lockheed dubbed the airplane the LMXT.

“Enhancing the capacity and surface architecture should be a top priority for the US Air Force—even if it comes at the cost of tanker procurement,” Hudson’s study says. Long-term, improving the infrastructure means more tankers and more fuel for more missions.

Comparing the KC-46A and LMXT

The executive summary sets the even-handed tone in Hudson’s analysis of the two tankers.

“The LMXT provides greater offload capacity than the KC-46A, which could allow it to support missions with fewer aircraft, thus saving operating costs on some missions during peacetime…and reducing operational complexity during crises…,” Hudson concludes.

But “the smaller KC-46As generally higher fuel offload to ramp space ratio means that for a given airfield, the KC-46As may be able to deliver more aggregate fuel capacity and booms in the air than the LMXT, and the US Air Force could avoid incurring some costs by selecting the KC-46A and increasing commonality throughout the fleet.”

Hudson goes on to discuss the advantages and disadvantages of each tanker in a dispassionate way that contrasts favorably to Thompson’s entirely political approach to the looming competition.

Hudson doesn’t ignore Boeing’s struggles with the KC-46A. The Boeing tanker has been beset by problems and delays. The USAF received only 47 tankers through August instead of the planned 143 by year-end.

“Furthermore, continued problems with the KC-46As aerial remote vision system and other systems mean that those aircraft that have been delivered may not be certified for full operations until 2024 or later…,” Hudson writes.

Statistical data

Several statistical tables present easy-to-compare data between the LMXT, KC-46A, and future tanker concepts. The LMXT needs 1.29 parking spots compared with the KC-46A’s 0.88, using the Boeing C-17 as the baseline. The empty weight of the LMXT is 23% more than the Boeing but carries only 21% more fuel for off-loading. Hudson calculates that the KC-46A costs $191m and the LMXT will cost $225m, or 16% more—a greater spread than between Boeing and Airbus in the KC-X competition that Boeing won. (There will be more on this in a coming series on the KC-X competition that begins next week.)

There is much more data in the study that is instructive for reporters who will be covering the competition.

Hudson concludes that “Overall, significantly fewer LMXTs are required than KC-46As…to accomplish the same missions; although, as the LMXT is larger, more ramp space is usually required to support the same number of receiver aircraft.” Hudson says that up to a third fewer LMXTs could be required because of the larger capacity and greater range.

But “When ramp space limitations are accounted for, groups of KC-46As can offload more fuel than groups of LMXT tankers,” offset in part by a need for more ground equipment and personnel. Also, Hudson writes, the KC-46As can operate from shorter, less firm runways when fully loaded. But if carrying the same payload of fuel, the LMXT has a thrust advantage to operate from the same or even shorter runways than the KC-46A.

In contrast, Loren Thompson not only ignores this kind of data in his advocacy for Boeing, but he also ignores Boeing’s own miscues, blaming the $5bn in write-offs the company has made so far entirely on Airbus’ illegal subsidies.

If this line of reasoning is the best Boeing can argue for KC-Y, it deserves to lose the next round.

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“Scott has written a lively and candid successor to “The Sporty Game.” Scott’s breadth of access to industry luminaries, who spoke so candidly, really made this book. Even in retirement, Connor, Leahy, and others are like war horses who continue to throw grenades while at the same time, offer candid mea culpas on the part of the company’s arrogance, product short-comings, and billion-dollar miscalculations.”

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“As an aerospace reporter, I was there for much of the last decade, and I can count on one hand the people who rival Hamilton’s industry connections and his grasp of details. He draws on both to tell the story of the biggest business brawl in recent decades.”

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72 Comments on “Pontifications: Think tank analyzes KC-Y competitive landscape

  1. KC-Y: Best option: A 251 metric tonne MTOW A330-800 LMXT with a fuel capacity in excess of 130,000 kg and with the A345´s Rear Centre Tank (RCT) integrated in the aft lower lobe.

    KC-Z: Option: A410XT using the A400M wing (and engines) which would be mated to the top of a modified and shortened A33o fuselage while using the same in-service ARBS boom as the A330 MRTT (i.e. keeping in mind that the 222-inch diameter A400M fuselage is derived from the 222-inch diameter A330 fuselage). MTOW of 160,000 kg and fuel capacity increased to, at least, 70,000 kg and with additional fuel tanks located in the lower fuselage. A modified A400M MLG would be integrated with a highly modified circular centre section, derived from the flat bottom A400M centre section.

    Hence, a KC-Y based on the LMXT and a KC-Z based on a Mach 0.72 capable and highly maneuverable, A400M-derived A410XT, would share the same basic cockpit and refueling systems.

    Hmm, what is not to like? 😉

    • just about everything, from a rational perspective 🙂

      KC-Y is effectively a “COTS” effort – looking to buy off the shelf either the current KC-46 or the boom equipped version of the MRTT with american commo gear. there is no money, time or political appetite for another developmental tanker, which an A330-800 based solution would be.

      KC-Z – first of all, the USAF would never buy a prop job tanker for refuelling jets (which is what KC-Z is for. KC-130J already exists for helos and other slowpokes), second there is a strong probability that KC-Z will be a clean sheet design with LO features designed to support B-21, F-35, F-22 and F-next in semi contested forward areas. there is also a strong possibility it will be either unmanned or optionally unmanned.

      • Reality is that LM + Airbus + A330MRT + US Production is money on top of money on top of money.

        The A330MRT does not stand a chance in a cost shoot out (let alone an A330NEO-MRT).

        What is missing is assessment of attack packages and how many aircraft in one of those vs booms available.

        There is a balance in fuel up and wait while others fuel up and then if too long, having to fuel again.

        If the KC-135 is ancient I hate to think what that makes me (and Scott! – fossils?)

      • @bilbo

        Hmm, it’s highly entertaining to observe the “buy American crowd”, which appear to be getting ever more desperate in their calls for the USAF to never ever acquire a single major European designed military system, and seemingly therefore, are left to resort to use distorted “facts and figures” and silly arguments — never mind taking into account (i); one of the most screwed up programs in Pentagon history (KC-46) and (ii); that European nations regularly buy C-130Js, P8-As, F-16s, F-18s, F-35s (etc.) in large numbers and (iii); that the U.S. has a massive trade surplus in arms sales and defense trade with countries in the European Economic Area (EEA). 😉

        Now, converting an A338 to a MRTT configuration would only require a Supplemental Type Certificate (STC) since all A330 types share the same Type Certificate Data Sheets (TCDS).
        Of course, this would lead to slightly increased costs for which Airbus would pick up the tab, since the A338 MRTT would become the de-facto Airbus large tanker offering from the end of the decade.

        As for “low-observable” features, didn’t you read the linked paper by Timothy A. Walton & Bryan Clark?

        To ensure the Bridge Tanker paves the way for a new tanker, throughout the 2020s, the US Air Force can methodically fund technology maturation, design, and prototyping efforts for capabilities to enhance the survivability of existing tankers and can launch the follow-on K-Z program. The K-Z tanker should likely be a dedicated medium tanker, termed K Z(M), that is efficient in terms of fuel consumption, fuel offload to ramp space ratio, and lifecycle costs and is capable of offloading fuel at range. A 95,000-pound (lb.) empty weight K Z(M) with 140,000 lb. of fuel appears to be a promising design that could offload relevant quantities of fuel to packages of small aircraft or one or more larger aircraft and would be capable of operating from a wide range of airfields near and far from fuel delivery areas. By adopting a balanced approach to survivability, the K-Z(M) could leverage a medium-sized fuselage, signature management best practices, and robust protection systems to allow it to operate slightly inside contested areas. Because it would remain outside highly contested areas and could defend itself against some missile threats, the K-Z(M) would not require a highly stealthy design, and its RDT&E and procurement costs could be reduced relative to a more sophisticated aircraft. If the necessary technologies are matured, making the K-Z(M) a highly automated unmanned aircraft would confer significant operational and lifecycle cost benefits.

        Now, despite your claims, the Mach 0.72 capable A400M routinely refuels fighter aircraft — in contrast to the slow-moving Mach 0.59 capable C-130J :

        A400M & Tornado Jet-Fighter Air Refueling! Full DUAL Ultimate Cockpit Movie (AirClips)

        Hence, an A400M-derived, A410XT KC-Z tanker that would use the very capable A400M defensive aid suite, would obviously tick all the boxes for the KC-Z requirements put forth by Walton and Clark.

        • Correction:

          The last two paragraphs came out wrong. They are not part of the excerpt from the paper by Walton & Clark.

          It should read:

          Now, despite your claims, the Mach 0.72 capable A400M routinely refuels fighter aircraft — in contrast to the slow-moving Mach 0.59 capable C-130J :

          A400M & Tornado Jet-Fighter Air Refueling! Full DUAL Ultimate Cockpit Movie (AirClips)

          Hence, an A400M-derived, A410XT KC-Z tanker that would use the very capable A400M defensive aid suite, would obviously tick all the boxes for the KC-Z requirements put forth by Walton and Clark.

        • @ov,

          I’m not part of the buy american crowd. I agree, the KC-46 development has been a sh*tshow.

          I’d be fine with it (and would have been fine with it before) if the USAF bought the KC-30/MRTT/LMXT or whatever they call it next week. it’s a good plane that has already gone through its growing pains. but adapting it to US reqs will cost money, the aircraft itself is more expensive & it is larger than the current physical infrastructure is designed to support. no matter how you look at it, bringing in a second type will increase lifecycle costs to the AF.

          as for my above statement about the KC-Z: did you read what I said? clean sheet (i.e. not commercial derivative), SEMI contested areas, LO features, not HIGHLY contested, full stealth.

          read your own quotes: “The K-Z tanker should likely be a dedicated medium tanker” (AKA clean sheet because the numbers they follow up with don’t align to _any_ commercial aircraft)

          ” signature management best practices, and robust protection systems to allow it to operate slightly inside contested areas”, huh, that looks an awful lot like LO features and semi contested areas.

          and given the development history (and ongoing reliability issues) of the A400, why exactly would we want to buy a highly modified derivative that would be too heavy, too slow and nowhere near even a little LO? an A400 derivative would not even be able to support a transatlantic fighter drag because it couldn’t keep up with the fighters, which typically refuel 3-4 times each during a crossing, and so fly in formation with the tanker for the entire crossing.

          • @bilbo

            As usual, too much is made out of the extra costs for an Airbus tanker. For example, the development of the Air Refueling Boom System (ARBS) was an Airbus (EADS) self-funded research and development effort. Airbus and Lockheed will IMJ only have to spend a fraction of what Boeing has already lost on the KC-46 on developing the LMXT KC-Y tanker (i.e. total KC-46 cost overruns now apparently exceeding $5 billion for which under the terms of its fixed-price deal with the USAF, Boeing must pay out of pocket for any expenses over the $4.9 billion R&D contract value).

            no matter how you look at it, bringing in a second type will increase lifecycle costs to the AF.

            If lifecycle costs were the determining factor (i.e. another nonsensical argument in order to try to middle the picture with respect to a possible LMXT acquisition by USAF), the USAF would never have contemplated launching KC-Y and KC-Z follow-up programmes following the initial KC-X programme. Nice try, though.

            Now, the A400M can already operate slightly inside contested areas, so your “concern” about the defensive aids suite for self-protection of an A410XT tanker, is really a non-starter.

            Of course, an A410XT KC-Z tanker would have major in-theater operational advantages. It would have a robust landing gear (i.e. A400M-derived) and the positioning of the engines on the high wing would make it less likely to ingest foreign object debris, which for example, would enable operation from runways that have been repaired after attacks.

            Walton & Clark:

            Additionally, the thrust, weight, and gear structure of tankers affect the length and firmness of necessary airfields and, in turn, the locations where tankers can operate. Access to more airfields (provided the airfields have fuel) can enhance operational resilience. Figure 28 shows how the lighter-weight K-Z(M) and K-Z(S) concepts, by being able to operate from runways 6,000 ft or greater and with less-firm surfaces, could operate from more airfields when fully loaded than existing tanker designs.119

            Access to more airfields is an operational benefit. However, perception of this advantage should be tempered by an un- derstanding of available ramp space and fuel stores at airfields. For example, on US and allied territory in the Indo-Pacific, the K-Z(M) design could access twice as many airfields as the KC- 46A, but it is only able to access 18% more ramp space, since approximately 93% of ramp space in the theater is located at major airbases or airports or minor airbases. Consequently, there is likely a promising middle space in which K-Z designs can operate from shorter runways (such as 6,000 ft or greater) and surfaces with less firmness than larger aircraft; however, the expense and weight of higher-thrust engines required to allow tankers to operate from very short runways may not be worth the effort, as there may be insufficient fuel and ramp space at those locations to support operations.120 An exception to this observation is adding features to tankers to enable operation from runways that have been repaired after attacks, such as incorporating robust landing gear and positioning engines in locations that are less likely to ingest foreign object debris.

            Quote from Bilbo: “and given the development history (and ongoing reliability issues) of the A400, why exactly would we want to buy a highly modified derivative that would be too heavy, too slow and nowhere near even a little LO? an A400 derivative would not even be able to support a transatlantic fighter drag because it couldn’t keep up with the fighters, which typically refuel 3-4 times each during a crossing, and so fly in formation with the tanker for the entire crossing.”

            The A400M is by far the most advanced military transport aircraft in the world and it has no worse development history (and ongoing reliability issues) than, for example, the C-5 and C-17.

            Now, the A400M can accommodate a wide range of speeds for air refueling, from 105 KIAS (Knots-Indicated Air Speed) for helicopter re-fueling to 300 KIAS with the Eurofighter.

            In contrast, the KC-135 can accommodate a range of speeds for air refueling, from 200 KIAS with the C-130J to 320 KIAS with the B-1B.

            So, what’s the issue?

          • @OV

            the USAF will not buy a M .72 tanker when all the planes they want to refuel cruise at M .85. again, an A410XTZZTOPNINJABOOM would not be able to perform a simple fighter, bomber or cargo drag across the atlantic, where the fighters/bombers/cargo and the tankers fly in formation and refuel several times during the mission.
            this is one of the most common tanker missions. to do this with an A400 derivative, you would need 3 or more A410XTEAGLEDEATHCLAWs staged out and perfectly timed to rendezvous with the fighters along the way.

            you must have me confused with someone else, because I never expressed any “concern” about defensive suites. nice try though.

            and if you think lifecycle costs are not going to play into this decision, I have a nice bridge in brooklyn I can sell you.

            WRT a tanker with soft field capability – the USAF won’t care. all their ops are based around hard fields, with only pure cargo planes having _any_ soft field capability. the aircraft the tanker is supporting all require long hard fields, so if those don’t exist, the tanker is moot anyway.

          • Phew, the absurdity of an A400 tanker boggles the mind. While the cost vs return is beyond belief, as is the fuel offload as is the boom issue.

            I would love to see the boom design for one though!

          • @TransWorld

            Why don’t you just read the paper by Walton and Clarke. It’s all in there.

            What they are proposing is a “medium tanker” for the KC-Z.

            KC-Z is not KC-Y – OK?

            Quote by @TransWorld: “Phew, the absurdity of an A400 tanker boggles the mind. While the cost vs return is beyond belief, as is the fuel offload as is the boom issue.”

            Well, the A400M can already function as a tanker:


            Now, would the all new medium tanker proposal by Walton & Clarke have a “cost vs. return that is beyond belief”, or is that type of hyperbole only reserved for any Airbus derivative aircraft?

            Now, my A410XT proposal is likewise a “medium tanker”. It would have exactly the same boom as the A330 MRTT. In fact, it would have a shortened (A310-size) A330 fuselage with the A400M wing mounted on top of the centre fuselage section. That’s not too hard to comprehend, is it?

          • @bilbo

            Again, this is not about what you believe the Pentagon wants, but rather what type of tanker Walton & Clarke is proposing for the KC-Z. Their “medium” KC-Z(M) will not be able to support your transatlantic fighter drag. With 179 KC-46 tankers and 140-160 KC-Y bridge tankers, why would USAF need that capability for the KC-Z?

            Now, if you’d actually read their paper, you should have been able to recognise that an A410XT type tanker would fit their KC-Z(M) requirements nicely.

    • This started of as a good read but then it became brilliant. Any 6 year old could see it, why couldn’t we? Lego should be invited into and integrated into Airbus Immediately. What is missing in this Hispano Franco German operation is Danish precision modularity.

      • Actually, the Soviets were the masters of “LEGO-engineering”:

        The Tu-114 used the basic wing, empennage, landing gear, and powerplants of the Tu-95 bomber, mated to a totally new pressurized fuselage of much larger diameter. To cope with the increased weight, increased landing flap surface area was required, and the flap chord was increased compared to the bomber’s flaps. The wing was mounted low on the fuselage, giving the Tu-114 a much higher stance on its landing gear than the bomber. As a result, a new nose landing gear strut was required, although the main landing gear remained unchanged.



        Now, in contrast to the TU-114, an A410XT KC-Z tanker would have the same fuselage diameter as the A400M, which means that the A410XT tanker would have exactly the same wing-to-body fairing (and internal systems that are located under the fairing) as the A400M. Also, a slightly modified (at the base) A400M T-tail empennage would be mounted on top of a slightly modified A330 aft fuselage section (i.e. Section 19). Hence, we’re talking about massive savings over what would be required for an all new KC-Z tanker; developed along the lines suggested by Walton and Clark.

          • Why make a new plane that is ‘A330 like’ when you have the A330. T

            If they need an even bigger tanker the A350-900 or A350F is there too, only a few metres more in length but a bigger wingspan and of course the costs of adapted it to the MRTT configuration

          • @Dukeofurl

            What’s most baffling is how @bilbo, @Transworld and @Dukeofurl all seem not to have bothered reading the paper by Walton and Clark, which of course, is the main premise of Scott Hamilton’s comment.

            Walton & Clark is proposing a “medium” tanker for the KC-Z. Now, I’m also proposing a “medium” tanker for the KC-Z (A410XT) — and again, the KC-Z is not the KC-Y.

            So, why all the controversy?

            Now, the “medium” tanker concept would have an OEW of 95,000 lb and a fuel capacity of 140,000 lb.

            The K-Z tanker should likely be a dedicated medium tanker, termed K-Z(M), that is efficient in terms of fuel consumption, fuel offload to ramp space ratio, and lifecycle costs and is capable of offloading fuel at range. A 95,000-pound (lb.) empty weight K-Z(M) with 140,000 lb. of fuel appears to be a promising design that could offload relevant quantities of fuel to packages of small aircraft or one or more larger aircraft and would be capable of operating from a wide range of airfields near and far from fuel delivery areas. By adopting a balanced approach to survivability, the K-Z(M) could leverage a medium-sized fuselage, signature management best practices, and robust protection systems to allow it to operate slightly inside contested areas. Because it would remain outside highly contested areas and could defend itself against some missile threats, the K-Z(M) would not require a highly stealthy design, and its RDT&E and procurement costs could be re- duced relative to a more sophisticated aircraft. If the necessary technologies are matured, making the K-Z(M) a highly automat-ed unmanned aircraft would confer significant operational and lifecycle cost benefits.

            Hence, this is not about making a bigger tanker, but adapting existing technologies and in-production hardware, into a “medium” tanker.

            An A410XT would not be “A330-like” with respect to performance (i.e. A310 sized fuselage using the A330 cockpit and tail section; shortened A330 fuselage sections; A400M wing (A310-size) and engines; A400M T-tail; A400M MLG etc.).

            An A410XT would, therefore, meet the medium tanker requirements for the KC-Z(M) proposal, suggested by Walton & Clarke, but would, of course, not meet the KC-Y requirements — which, of course, it’s not intended to meet.

          • The KC-46 is already the ‘medium tanker’.

            if they want an even smaller one ( around 100,000 lb OWE) they will develop it out of existing narrow bodies as thats ‘the number’ for the 737 Max.

            The A310 had an OWE of around 175,000 lb as it really was a development of A300 to match the 767. the A400 is up around that number too and its wing is sized and strengthened for its 300,000 lb max TO weight. The A330 horizontal and vertical tail is already composite rather than grafting a T tail on from the A400

          • @Dukeofurl

            The KC-46 is more capable than the KC-135. Therefore, it’s not really a “medium” tanker.

            The A400M fuselage (cockpit to tail) is significantly heavier than the similar sized A310 fuselage. OEW for an A310-sized A410XT tanker would be slightly more than the OEW of a 757-200 and slightly less than the OEW of a 757-300 (i.e. less than than 140,000 lb).

            Of course, retaining the A300 empennage (minus the too large horizontal stabilizer) is an option. However, the T-tail ensures the tailplane surfaces behind the wings are out of the airflow. This ensures smooth flow and better pitch control of the aircraft at low speeds.

          • The KC-46 is the medium tanker , an A330/KC-30 or a KC-777 is the larger end.
            The possible single aisle 737 type would be the lower end.

            The OWE numbers confirm this and the KC-46 has just ‘a bit more’ fuel offload capacity ( 212,000 lb) than the KC-135R (200,000lb) which was intentional. Yes it can fly further because of more economical engines.

            You still havent come up with a 100,000 lb OWE aircraft of any description.. with your lego approach. Anyone else can see the 737 Max is that plane , but rightly so ,no one wants that. The 737-800 as a freighter can carry about 25 tons of payload

          • @Dujeofurl

            Again, it’s how the tanker sizes are defined by Walton & Clarke that’s the premise for this discussion. Not yours, not mine (i.e. KC-Z(Small), KC-(Z)(Medium) and then; the larger tankers (KC-135, KC-46, A330-MRTT and KC-10)).

            Hence, the KC-46 is not a “medium tanker” according to the authors.

            Now, the whole point about an A410XT tanker would be to take maximum advantage of the existing refueling capabilities of the existing 0.72 Mach capable A400M (i.e. the A400M wing and engines and probe-and-drogue system), and then add the Airbus Aerial Refuelling Boom System (ARBS) on an optimised fuselage that would be mated to the A400M wing, in order to be able to offer a truly “medium” tanker.

            The cheapest way to develop such a tanker would be to re-use the same diameter A330 fuselage. However, overall fuselage length (i.e. cockpit, fuselage and empennage) would be similar in length to the A310, not the A330-200.

            Of course, that doesn’t mean that other lighter options are not available, such as using the smaller A321 fuselage instead

            Mating the A400M outer wings wings to an A321 fuselage would require using a smaller (i.e about 1.5m narrower) centre wing box to which the existing A400M outer wing box(es) would be attached. The (A321) lower fuselage would hold additional fuel (i.e. same arrangement as the KC-135).

            With the low weight of the A400M wing, and the smaller A321 fuselage, the OEW of this notional A421XT tanker should not exceed 100,000 lb.

            It’s at this facility that Airbus completes the complex task of integrating wing spars, wingskins and an assortment of other large carbon fiber composite structures into the A400M’s massive wing before equipping the structure with an array of complex systems, covering “fuel, electrics, pneumatics and hydraulics.” In addition, the plant installs all fixed and moveable structures, including trailing-edge devices (e.g., ailerons and flaps), leading edges and wingtips. This assembly effort represents one of the largest such operations in the world, producing a wing that weighs only 6500 kg/14,330 lb, but can contain and carry aloft as much as 25,000 kg/55,116 lb of fuel.


    • That story of the ‘re-used A330 222 in fuselage has been arounnd for a while

      Not quite
      ‘When we did that we realised the upper diameter was only a few centimetres less than the cross-section of the A330/A340. So we decided to set the diameter to the same amount for commonality. Not a single frame is the same, but by sharing similar dimensions we can use many of the same parts of the manufacturing and assembly process such as the stretch-forming tools and panel-carrying trolleys.”

      ‘Not a single frame is the same’ but the panel carrying trolleys get a second life along with the thin skin forming tools

      • @Dukeofurl

        The whole point being that with the same fuselage diameter (i), the A400 wing (and engines) and (ii), the entire unmodified A400M wing-to-body-fairing, and (iii), most of the centre fuselage section with the large cut-out on the top (i.e. except for the flat bottom) would be re-used on an A410XT KC-Z tanker. The fact that no single fuselage frame in the centre section is similar to A330 fuselage frames, doesn’t prevent major A330 forward and aft fuselage assemblies being mated to a “circularised” A400M centre fuselage section.


        • Its a crazy idea.
          The A400 fuselage section is almost circular anyway, that was the whole idea of reusing some skin and panel tooling for the same dimensions.
          The framing had to be different because of heavier loads , above fuselage wing and the undercarriage location.
          The flat section loading area comes from the across the bottom of the ‘almost circular fuselage’ like the do for belly cargo pallets. The passenger flat floor comes across the mid section.
          The whole USAF request is based on in production airliner , not a new development of a franken-plane.
          Theres a very good dimensioned diagram in this blog ( in french) , down the page, from a Laurent Simon which shows the circularity of the A400 . The C-17 is definitely pear shaped fuselage but other smaller planes are fairly circular too. Of course the actual load area is a ‘box’ inside the airframe

  2. the LMXT may be at a major cost disadvantage because it _will_ require some significant redesign from the current in production MRTT due simply to some of the same issues that caught Boeing out with the KC-46 (wiring separation, hydraulics separation, other US Mil standards). Boeing will come in with a “We’re 100% done with development” 767 pricing. LM/AB will have to either eat a lot of cost (as Boeing did on the KC-46 initial contract) or convince the USAF that fewer booms for the same money is somehow better.

    I am not convinced that the “well, you don’t need to buy as many LMXTs because they carry more fuel” argument will fly as (historically) the USAF has favored more booms/less fuel/more orbits over fewer booms/more fuel/fewer orbits.

    Boeing will also be able to argue they have better total program lifecycle costs because the KC-46 is already in the fleet, the training pipeline, simulators, maintainers and maintenance equipment and depos are already in place, it fits on the existing ramps and in the existing hangars.

    the USAF also will go to great lengths to avoid spending any money on extra ramp space or new hangars. for some reason the idea of spending $100M on base improvements that would enable massive capability increases at a base always comes second to $100M for one more fighter jet.

    • I agree. Boeing can offer a mostly functional aircraft and a running production line. The Airbus offer comes with more cost and time risks, even though the company currently is much better at program execution.
      However, the competition allows Airbus to put price pressure on Boeing.

      • What is being ignored.

        1. Setting up an assembly line in the US, for the A330CEO.

        2. LM exist on high cost defense products, ergo, no profits here

        3. Airbus needs to make a profit.

        The bizarre thing is that LM has jumped into this. The only remote thing is they are setting themselves up to bid on the KC-Z. Maybe the bid process is rubber stamp stuff and low enough cost.

        By the time this comes to light of day Boeing will have the boom issues fixed.

        Hats off to Airbus for both the boom development/vision system and the move to automated fueling.

  3. Was/is lack of ramp space also an issue for the huge LM C-5 Galaxy transporters?
    And the USAF has no problem finding room for its 223 C-17s.

    Wouldn’t it be nice if LM/AB just did us all a favor and stopped this circus? Even if the USAF wants the LMXT, lobbying / lawsuits / backroom politics will just divert the order to Boeing — same as last time.
    Is there no better use for the time and money that will be wasted on this “contest?

    • I think the only reason why Airbus even bothers taking part in this rigged circus is to make sure Boeing can’t just quote whatever it pleases and use it to recoup some of subsidies lost due to the WTO case.

    • yes, but the govt bought in from day 1 that new ifrastructure would be required because the C-5 was a whole new category.

      the C-17s basically replaced the C-141s (on a less than 1 for 1 basis) and are of very similar dimensions and easier on the pavement.

      Hopefully LM can at least force Boeing to come in cheap.

      • Bryce engages in his usual what absolutism’s.

        First, tankers do not operate like freighters. Ergo, tankers are stationed at a field, a C-17 flies in and out. LOL, implied all C-17s at one base. Wow.

        The C-5 is a Strategic Airlifter. While its capable of short and soft field, that is not its role.

        In turn, while the C-17 flies international missions, its key role is distribution out of a C-5 airport (big regional out of combat zone).

        In that regard the A400 and C-17 are somewhat contemporaries with a nod to the A400 for smaller and tighter fields. C-17 can carry an Abrams MBT that the A400 cannot.

        The there is the C-130. France and Germany are both operating the latest J model as there is a need for something smaller than the A400 tactically.

        Sans an emergency you don’t want to risk a C-17 or an A400 in a hot combat zone.

        Nor would you station a tanker that close to a hot zone that it could get taken out (given that even regional fields are withing long range missile attack – ergo the Anti missile defenses do have to work)

        • TW engages in his usual name-calling and waffling when someone makes a point that he finds difficult to refute using logic 😏

  4. Well, we have now actually got some pictures to look at regarding the A350 paint problems. Appears to be a simple though serious primer adhesion problem. Why is it so hard to deal with? Is the copper corroding?Release agent contamination? The only issues I have seen like this have turned out to be fairly basic compatibility problems.
    I think that you could describe it as a bit more than a “cosmetic” problem.

    • A typical repaint cost on a B777 according to American Airlines is $100k to $200k. Using that as an indication I’m assuming this is going to cost around $500k per A350 given the replacement of the protective coating may be involved and that would be far more complex. Given that there have been 443 deliveries to date this could be a $220 million dollar boo boo.

      • If Airbus can really fix the problem once and for all for $220 million, they probably won’t be too unhappy. At least it ends a damaging quarrel with an important customer and removes uncertainty that might be felt by other potential customers.

        • I suspect it could head well North of 1 million dollars per aircraft. The issue (worst case) may be hydrogen formation from galvanic corrosion between the copper and the carbon fibre. This is a problem Boeing discovered and gave them difficulties. The copper may also need something to bond it into the protective layer. All of these measures may add thickness or weight. Once issue will be oxide formation and corrosion on the copper which must provide lightning strike protection.

  5. I’ll see if I can get someone to buy me the book for Christmas. If not then I’ll buy it for someone else and borrow it back.

  6. Ten years to select from 2001 to 2011, and then ten years until 2021 to deliver the first 50. At that rate, I’m not holding my breath for any future selections.

    • The military-industrial complex (in the words of D.D.E.) is good at sucking its host (almost) bone dry.

  7. Sorry for the off-topic excursion but further details have finally emerged today concerning the nature of the paint degradation issues on the A350…including some very detailed photos on Reuters.
    There’s a bonding incompatibility between the paint and the underlying copper lightning conduction mesh:
    “At the root of these problems is the new material used in the construction of the A350. Rather than an aluminum body, the A350 follows the Dreamliner in having a composite fuselage. With a non-metal body, the aircraft needed a mesh installed for lightning conduction. This makes it more difficult to get a good stick on the paint. Adding to the complexity is the fact that, like metal, paint expands and contracts with changes in temperature, while carbon fiber does not.”

    Another five airlines are now reporting this problem. Although the issue is being labeled as “cosmetic” (except by Qatar), it’s a nasty headache for Airbus, and is no doubt costing them a bag of money. Some of the photos reveal a condition that appears more severe than just “cosmetic”.

    Three links: Simple Flying, BNN Bloomberg and Reuters. Although the Reuters link is behind a firewall, the detailed photos can be scrolled through outside the paywall.




  8. That report is going to take a lot of time to digest (for those who actually read it)

    I don’t see the 23% more weight vs 21% more fuel as “mere”. It is in line with you got to be bigger to carry more and its only a 2% difference.

    Reality is you don’t get equal numbers of tankers and the KC300MRT would have to offer a large benefit in ops to offset it much higher costs and how many you can park on an air field vs how many you will need.

    I have yet to see a conflict that they had more tankers than they needed.

    You can rob Peter to pay Paul, but longer term that impacts the overall and becomes a deficit. You do it if you have to and watch the deficit side to minimize it or understand what its doing to your ops.

    • The “reds” will be delighted if the USAF chooses the KC-46’s “limited ops”: there’s nothing as comforting as a military asset that can’t be deployed when it’s needed.

    • As a pax plane a330 had 20% more capacity for 10% more blockfuel.
      The a330 wears its weight rather well.

  9. On the subject of air force order contests, Boeing recently got a cold shower from Canada:
    “Canada Rejects Boeing’s Proposal For CF-188 Hornet Replacement Program”

    “The proposal based on the Super Hornet reportedly did not meet the requirements set by the government, leaving only two contenders for the new fighter aircraft.”

    All the more reason for Uncle Sam to give some badly-needed (life) support in the form of a nice bridge tanker order 😏


    • Well detailed article. The latest model of the F-15E+++ must come pretty close to meeting all the requirements. But than may not. There could still be some anti-Boeing sentiment lingering…

  10. I guess in a real conflict, say with china, you would want to keep refueling time as short as possible. You dont want to be a sitting duck longer than absolutely neccessary. Also more tankers means more redundancy in case some are shot down.
    The added fuel capacity of the A330 might make a difference for long range missions or not. 1/3 doesnt sound like a gamechanger at first glance.

  11. Dominic Gates:

    While Boeing is eager to put behind it the consequences of the two fatal 737 MAX crashes, Democrats on the U.S. House Transportation Committee chaired by Rep. Peter DeFazio are pushing for more individual accountability for what went wrong at the company.


    The Seattle Times:
    Democrats push FAA for action against certain Boeing 737 MAX employees

  12. Jack Welch’s influence on Boeing CEOs from Condit to Calhoun

    The Daily Beast:
    How Boeing Was Set on the Path to Disaster by the Cult of Jack Welch

  13. The decisions surrounding the next tanker purchase should ideally be made based on the warfighting ability of the aircraft. There are a few problems the MRTT has in a combat scenario. Its fleet puts fewer booms in the air forcing a longer tanking evolution for the strike package leaving them with less gas for the mission. There is also the undiscussed problem posed by bad guys bagging a tanker. The strike package fuel gets real iffy and divert fields, if there are any, come into play.
    Lastly, the RAF has shown us that tanker boom count matters. When the Victor missions were flown from Ascension Island to the Falklands, it took 15 Victors (all they could scrape together) and a Nimrod launching in 3 waves hauling over 2 million pounds of fuel to get 1 Vulcan and 7 bombs over Port Stanley. If the RAF had fewer larger Tankers with a lower boom count the mission would have been unflyable.

    Our Strike Pilots deserve the functionality of the KC46 with the higher boom count. Saving money with fewer MRTT based aircraft is ultimately false economy if you fail to win in wartime…..


    • They had to refuel the refuelers was one of the reasons so many tankers required. As well modern tankers can offload more fuel as they have more
      fuel efficient engines than those early 60s Conways on the Victors.

      In deed the RAF buying ex Tristars for refueling came out of the Falklands issues ( which was a pretty extreme circumstances). Interesting in a private provider wants to keep those Tristars flying as contractor support for military tanking

    • Blackbuck 1 could have been done with just 2 A330MRTT.

      Distance to target was about 6,500 km. Last refueling was at 5,600 km before target. One A330MRTT could have trailed the Vulcan to this point and fill it up without the need to refuel itself. A second MRTT is required to refuel the Vulcan earlier. With a third MRTT a second Vulcan would have had enough fuel to do the mission.

      With KC-46 the tanker needs itself a refueling of 10 t. A second KC-46 is not enough to refuel the final tanker and the Vulcan. A third KC-46 is required. For a second Vulcan 5 KC-46 would be required.

      Finally the RAF ordered the A330MRTT because of its supirior range with the Falklands still as an area of operations in mind.

      It’s about 6,500 km from Hawaii to Guam but booms are all that matters…

      • You are missing the point.
        Boom count gives you the flexibility to project strike groups large distances. The boom constraint doesn’t go away because you can get the gas to the tanking point. If the strike package takes twice as long to get off the tank point, it has less range as the last guy comes off the boom. This also means that the bigger tanker needs to be closer to the target to account for it’s longer evolution time. This increases the bad guys chances of a good intercept, and adds to mission risk…… Also, a tanker abort with a big tanker costs you a lot more mission capability than a smaller tanker abort….. It really is a numbers game and the numbers seem to favor the small tanker in wartime and the larger aircraft in non combat scenarios…… So it’s a matter of what you want to be good at, peacetime or combat….

        • It till be interesting to see how often the two probe and drogue is used on the KC-46 to refuel US Navy, Marine Corps, NATO and friendly aircraft.

          Presumably the RAF and French AF use the MRTT to refuel two Typhoon or Rafael simultaneously which eliminates most if not all of the ‘boom constraint’ issues.

          I’m inclined to think that should original EADS MRTT proposal for the USAF tanker reequipments have somehow ‘won’ that the USAF would now have a functioning fleet of tankers, maybe a billion in savings from retirement of early build KC-135 and about 6 billion in savings from cost over runs.

          Boeing would have won the money back in extra F-35A sales from the extra money the USAF had.

          So while the KC-46 may technically be the better suited aircraft when the dimensions of time and money are added I think it looks a mistake.

          At this point the damage is done and the KC46 is positioned to be the easy way forward.

      • @ MHalblaub
        Great points.
        Seeing as the USA is separated from all its “enemies” by oceans, you’d imagine that some more attention would be paid to range. Perhaps there’s just an assumption that the full scala of bases in foreign countries will continue to be made available indefinitely.
        The USAF chose the A330MRTT in the previous contest (before politicians forced the KC-46 upon them)… one can ask oneself why that choice was made. In the meantime, ramp space has suddenly become an issue.

        • The USAF was and is in need for a capable freighter aircraft with refueling as a secondary usage. It’s about 90 % freight and 10 % refueling. KC-135 fleet could get that old because it’s a one trick pony.

          The A330-200 still is the better freighter for USAF than a 767-200. USAF has quite different destinations compared to FedEx or UPS with 767-300F.

          In the last competition the fuel burn was doctored towards a lighter aircraft with 7 touch&go maneuvers on every flight the aircraft will ever make. USAF also had an additional competition for flight simulators making such training efforts abundant.

  14. Bigger, longer range tankers are better for black buck operations. Voyagers fly straight to the Falklands from Ascension whilst refueling fighters and carrying ground personal and equipment. NEO can fly even further and re engineing the B52 is going to massively increase its range.
    I’m not very clever but I make that about 2 MRTTs required, 1 on the way out and one on way back

      • I believe that they have only shipped out to the Falklands once like that when they first delivered the typhoons. I think this was just to prove it could be done in wartime. In all but the most dire circumstances you would probably have to add some more aircraft to refuel the SAR cover.

      • Actually following a bit more research, never!
        They do it all the time across the Atlantic and and there is a weekly passenger and cargo service from Ascension direct to the Falklands but I don’t think voyagers have deployed with fighters and I believe that the hanger at Mount pleasant is too small for the A330 to be based there.
        When the typhoons were delivered there were no voyagers and it took 2 tristars, 4 VC10s and 4 C130s

        • And in the Falklands, you really would need a hangar to put it in. The wind there can be really, really bad. Leave it outside and there’s a good chance that you’d come out to the ramp in the morning and go, “er, where’s the tanker gone? Anyone seen the tanker?” . “Ah well. Put the kettle on.”.

  15. Regarding the LMXT:
    “Airbus touts autonomous refuelling advance, as USAF tanker opportunity nears”

    “Airbus Defence & Space has announced plans to extend its work on automatic air-to-air refuelling – or so-called A3R – technologies by in the future incorporating fully autonomous functionality.

    “We are now on our way to get an autonomous air-to-air refuelling which is a kind of unmanned execution of the operation,” says Jean-Brice Dumont, the company’s head of military aircraft. Airbus has dubbed the planned advance A4R.

    “We see more and more with long-range missions for many aircraft, including combat aircraft, a need for predictable, deterministic, reliable air-to-air refuelling capability,” he says. With this in mind, the company is eyeing technologies which will enable the procedure to become fully autonomous, without requiring modifications to receiver aircraft.”


    • taking the humans out of the loop on aerial refueling (for both the tanker and the receiver) would be a huge advance.

      it would likely require some form of collaborative autopilot to ensure formation stability, and just leave the humans with their hands over a big red “abort” button.

      would likely require the ability for manual control to support older aircraft though.

  16. I think you hhave to get pretty creative again to make the KC-46 win this competion based on its track record and capabilities. Unless the USAF selects the Boeing, congress will jump in again and overrule them, like last time.

    If Boeing offered a KC777 for the Pacific, the ramp space discussion would implode in a fraction of a second.

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