New study on KC-X, and other news

There is a new report on the KC-X tanker situation, in this 16-page PDF. A hat-tip to Addison Schonland and IAG.

Airbus and Boeing aren’t rushing to re-bid on India’s tanker program after the country previously canceled a deal, according to Aviation Week.

Aviation Week also has this article: Additional fuel may pay off in tanker competition. Not good news for Boeing. This quote the 16 page report, above.

National Defense Magazine has this item: Northrop Grumman has no regrets walking from the competition.

DOD Buzz has this take on the above-mentioned 16-page report. DOD Buzz reports that the authors of the study have no connection to EADS or Boeing.

23 Comments on “New study on KC-X, and other news

  1. I find the concept of a combined tanker/surveillance scenario (Aviation Week article) rather intriguing.

    As for the Indian tanker competition, I suspect that at the very least, Airbus is more interested than they are letting on. Even though the USAF competition is for up to 179 aircraft, they could use those 6 sales if they don’t win that big one.

    • On the Indian subject, Do you have any reason to think the exact same doesn’t apply to Boeing?

      • Nothing concrete. But based on Boeing’s (and its supporters) comments/claims that the US would no longer have an american based manufacturer of aerial tankers, should they not win this deal, would lead me to believe that the USAF deal is an all or nothing issue for them. In other words, if they don’t win KC-X, they will give up the tanker business on their own, rather than continue to make sales of 4 to 10 tankers to various customers all over the world. Perhaps Airbus has the same plan in mind. But if so, they haven’t been so blunt about their intentions. Or perhaps the talk about no american tankers is merely a bluff on Boeing’s part.
        Only those at the top of these 2 companies know with any certainty.

      • Hadn’t thought of that yet… I think it would be likely Boeing quits the tanker game if they loose KC-X.

  2. I find it interesting that Ms. Grant chose not to fly the KC-135R at its full fuel load capability in her B-2 Pacific war mission, yet did fly the KC-10 with full tanks. Refueling a B-2 on such a mission the KC-135R would take off with full tanks, 202,000 lbs, not the 180,000 lbs she used. The 180,000 lb fuel load only applies if the KC-135R is equipped with WARPs, which would not be needed to refuel the B-2 bomber. Also, if a KC-10 were used on this same mission, only 1 KC-10 would be needed, not 4. The one KC-10 would escort the bomber through all four refuelings,then recover at a foreward base. There are 59 KC-10s in the USAF inventory and only 20 B-2s, so that can easily be done using only 1/3 of the KC-10 fleet. She also does not account for a tanker that breaks and cannot refuel after it takes off, which is why the USAF always plans in ground and/or air spare tankers.

    So, Ms. Grant is playing a numbers game to support her statistics in support of buying the KC-30MRTT over the KC-767NG or even reengining and updateing the KC-135E. Her theory on a fleet wide grounding of the KC-135 fleet also does not carry much water, as a fleet wide grounding can effect any airplane. In 2009, the USAF grounded the F-15, which is much younger than the KC-135. In 1979 the FAA ordered the DC-10 grounded after a rash of unfortunate accidents, that same year the USAF selected the DC-10 as its ATCA tanker. The jury is still out on the cause of the AF-447 crash in 2009, even though Airbus has declaired it “pilot error”.

    • Some very good points made KC, but I wonder can you provide evidence for “…Airbus has declaired it “pilot error””?

    • Great points TopBoom! She also ignores two very additional aspects – both that favor the smaller 767 tanker.

      1) In addition to the ground fueling capacity of the FOB, there is the parking aspect… many tankers (booms) can the airfield park. Sure some will generally be flying, but there are times when they all will be on the ground and you need a place to park them so that they can be quickly launched again. If you add the wingtip and taxi clearances, the footprint of the KC-10 is 152% of a KC-135, the 330 is 187% of a -135, and the 767 needs 138% of a -135. Using public source data of max fuel capacity, and dividing it by its own footprint I calculate the following pounds per square foot utilization: KC-135R; 6.9, KC-10 – 8.1 #/sqft or 117% of the -135, KC-330 4.6 #/sqft or 67% of the -135, and finally the KC-767 5.5 #/sqft or 80% of the -135. Clearly, the 767 & 330 are not as good in this measure as either the 135 or 10. But that is because they are designed to be efficient carriers of people or cargo, not fuel and used as tankers. But my point is that the 767 makes better use of the available parking space than the 330, and you can fit more 767’s (booms) on given ramp than you can with 330’s.

      2) Either/both tanker will be capable of being refueled itself thereby extending range and/or loiter time. The USAF does tank into account fuel savings when planning its tanker missions. In the case of fighter orbits, it is more efficient to use a smaller more fuel efficient plane to loiter and keep it airborne with periodic refueling than to take a larger plane with a larger fuel capacity and carry more fuel longer. With it’s huge capacity, I could foresee the KC-10 being the mother-ship delivering fuel to a pack of airborne KC-X’s that are orbiting over the fight. In the case of the long range bomber mission, you use the KC-10, or you send 2 KC-X’s and at some point the 2nd KC-X gives its gas to the lead KC-X and returns to base while the fully fueled lead continues to the bomber.

      • 1) how much more ramp space is available when you can fly 3 more hours before starting the circuit. how much bigger does the fuel availability become when you base your tankers at 2 or more bases rather than the closest you can find. How much more robust and survivable does that make your in-theater AFR capability?
        how much more operational flexibility does longer legs provide?

        2) it is generally not more efficient to fly a tanker to refuel a tanker. The waste is in the extra trips and takeoff/landing cycles. When your orbit is <500nm away from the base you may be right, but as the trip distance increases, the tanker bringing the fuel wastes ever more fuel.

        Anyway – all these points are moot if you accept that IFARA will comprehensive address all these concerns.
        Last time around, IFARA showed the bigger plane to be more efficient than the smaller option.

    • Another fault I see in Ms Grant’s “Tanker Offload and Endurance” chart in section 4: The 15%, 25%, and 35% notional airplanes are based on the fuel burn of the KC-135 with a 180K fuel load at take-off. In her chart, I note that the KC-135 uses 32% of its fuel at 500NM, 45% at 1000NM, 58% at 1500NM, and 83% at 2500NM. These percentages are carried through for the 15%, 25%, and 35% notional aircraft. I don’t believe that these percentages will represent the capabilities of either the KC-767 or the KC-330. Second, even if the KC-135 could carry that extra fuel, its fuel usage would necessarily have to rise to carry all the extra weight, thereby decreasing the offload available at those distances (you can’t carry 15/25/35% more without a penalty). The 2-engine aircraft will be more efficient than the 4-engine KC-135 and 3-engine KC-10. Both the 767 and 330 will have better numbers than the notional aircraft, but will differ from each other in percent used.

      A decent paper overall, but I also feel she has a bias. Nice pictures though.

      • You did notice the parts where she clearly states that the total equation is more complex and that those numbers are only for illustration, did you?

        The point I would make is:
        When you start with 25% more fuel, and your fuel burn per time/distance is less than 25% higher, your amount of offload fuel will go up relative to the baseline as you increase the time/distance

      • She’s using the correct USAF numbers (check the source). Perhas your feeling that she is supposedly biased is based more on tendency of yours (?) to discount facts that don’t fit your preconception…. 😉

        Table 10. Tanker Offload Capabilities (page 17).

        Aircraft..Max Offload Available

        …………Mission Radius

  3. Split the contract and employ 100,000 Americans ASAP on 2 production lines. Both Seattle (mostly white city) and Mobile (mostly black city) are both deserving of this work.

    • not to mention the likelihood that this KC-X is going to be the only new tanker program for at least another decade, possibly much longer. If the USAF wants to maintain a diverse fleet of tankers, they’ll need to buy all types now.

  4. The 180,000 lb. quoted for the KC135 I suspect is its 7000ft. runway limit.

    I do not believe too may airports exist with 7000 ft. runways where parking would be an issue between 767’s and A330’s.

    All in all a very interesting paper.

  5. There are thousands of qualified aerospace workers looking for a job, let’s put this thing to bed and start hiring people before the experience base goes away.

  6. KC135TopBoom, with all due respect, I find it interesting that you failed to recognize that Ms. Grant used Air Force Pamphlet 10-1403 since it is specifically referred to as a source (below the Tanker Offload and Endurance chart, page 7). She’s not making things up, but is using Air Force numbers correctly in her analysis. I’m quite surprised that both you and “GasPasser” failed to recognize that fact, and instead opting to somewhat belittle Ms. Grant.


    Table 10. Tanker Offload Capabilities. (page 17)

    Aircraft….TOW (lbs)..TOFL (lbs)

    KC-10…… 587,000….327,000

    1. This table was extracted from MCM 3-1, Vol II, Tactical Employment KC-135/KC-10, 10 May 95.
    2. Based on Sea level, standard day, 10,000-ft dry runway.
    3. Offload data based on 1-hour orbit.
    4. Cargo carried will reduce fuel load on a 1:1 basis.
    5. All KC-10 and a limited number of KC-135 aircraft are refuelable, providing increased range, offload, and loiter capabilities.

    18. Air Refueling Example (page 9).

    For this example, assume you need to deploy 6 F-15C’s from Langley (KLFI) to Spangdahlem (ETAD). How much fuel and how many tankers (KC-135R) are required? Note: For this example average/historical figures were used. Actual numbers would vary according to aircraft model, configuration, altitude, airspeed, etc.

    18.1. Onload Required (per receiver)
    = (dist / TAS x fuel flow) – total fuel + dest resv

    dist = total distance from takeoff to landing

    TAS = average airspeed of receiver leg (use Table 4. Blockspeeds for mobility aircraft or applicable flight manual airspeeds for combat aircraft.)

    fuel flow = fuel burn rate in lbs/hr

    total fuel = total fuel on board at takeoff

    dest resv = required fuel reserves at destination

    = (3500/480 x 10,822) – 23,000 + 7500

    = 63,410 lbs (per receiver) x 6 = 380,462 lbs

    18.2. Offload Available (per tanker)

    = total fuel – (dist / TAS x fuel flow) – dest resv

    = 180,000 – (3500/480 x 10,718) – 30,000

    = 71,848 lbs per tanker

    18.3. Tankers required

    = (offload required)/(offload available)

    = 380,462/71,848

    = 5 KC-135R’s required

    • First of all, I’m not questioning whether Ms Grant has correct numbers for the KC-10 and KC-135. I assumed she has those correct as I’ve seen her published in the Air Force magazine many times and I take her to be a credible source. Not an expert in tankers, but credible – I assumed she would be presenting factual data regarding the -10 and -135.
      What I am questioning are the “Notional aircraft” figures…..Where did she get/create that data? Having analyzed it, I uncovered that she used the same percentages generated by the KC-135.
      At 500 NM, the KC-10 has an available off-load of 233,500 #’s, meaning that 93,500 #’s were for its own use (327,000 @TO – 233,500 off-load = 93,500 for own use). That equals 29%.
      For the KC-135 at 500NM, these figures yield 57,800 #’s or 32% for its own use.
      The 15%, 25%, and 35% notional aircraft all also used 32% at 500 NM. Hmmm, that’s an odd coincidence! The numbers for these notional aircraft yield the same percentages as the KC-135 at all distances. (That’s no coincidence, that’s a pattern!) So clearly, this is how she came up with the off-loads for these notional aircraft in her paper….by extrapolating the KC-135. This is where I have to raise the BS flag. She didn’t try to get 767 or 330 data. The problem is some readers will think that those numbers represent the contenders. As I saw the percentages used for the various distances – there are differences between the -10 and the -135. I am certain that the 767 and 330 would differ as well based on their differing efficiencies.

      • Well, you didn’t point out to KC135TopBoom that he was erroneous and wrong and that Ms. Grant was using correct numbers from Air Force Pamphlet 10-1403. Instead you complimented him for making “great points”. If you assumed that she was using correct numbers, why didn’t you say so?

        As for your “percentage figures”, has it occurred to you that she may have used the numbers for the KC-135 and not the KC-10 simply because the KC-X is meant to replace KC-135s and not KC-10s and that the fuel burn rates of the KC-767 and the A330MRTT are respectively slightly lower and slightly higher than that of the KC-135, but still significantly less than that of the KC-10.

        The truly interesting number in a KC-135 and KC-10 performance comparison is how much better the latter performs as the mission radius increases. At 500nm the KC-135R/T can offload 52,3 percent as much as that of the KC-10, (newer aircraft , better wing even though the KC-10 is a WB and the KC-135 is a NB), but as the mission radius is increased to 2500nm the KC-135R/T can only offload 39,1 percent as much as that of the KC-10 (using the numbers from Air Force Pamphlet 10-1403). Coincidentally, the same comparison can be made for the KC-767 and the A330-MRTT. As the mission radius is increasing, the difference in the offload capability of the two contenders is increasing as well (in favour of the A330-MRTT).

      • If you look at the much vaunted pamphlet, it also includes fuel burn rates Table 9 (An F22, F15 burns it as fast as an KC135R – damn).
        Happily, T9 also provides fuel burn rates for the B767. Not the A330 though. No matter – Assume it to be 20% higher (probably conservative:

        A couple of interesting things pop up:
        1) the A330 fuel available ratio compared to B767 goes up.
        (it starts with 25% more fuel and burns “only” 20% more)
        2) At 2500nm the A330 can offload as much fuel as an KC-10
        3) I can consistently park an A330 500nm further out and still offload the same amount of fuel as an B767, relieving forward bases. At these assumptions, this would make the A330 9% less efficient compared to B767 (at 500nm closer)

  7. Peter Johnson and Jay are right. Analyze the numbers all you want, but they do not matter because right now “its all about jobs, stupid.” The NWest has aerospace jobs aplenty and the SEeat does not. IMHO this means that AB wins so long as they put an assembly line in Alabama and use as many US mfred parts (engines and elctronics in particular) as possible. How this is done will involve diplomatic negociations with the EU on how much of each plane will be build in Europe. The goal will be to get to “yes/win-win” for all concerned, ie the NWest, SEast, and the EU even it cost more than would be ideal. Thus, there is likely to be a substantial sweenter to the NWest, My guess is that the AF has delayed uts decison because they need more time to get to “yes;” and Obama will intervene after the election to get the job done with the support of all Congressional delegations involved.

    Also, note how the emphasis on refueling at long ranges reflects the US’ strategic weakness in WestPac. We do not have the bases there that we used to, particularly Suboc Bay and Clark Field, so Guam is the nearest place from which tankers could operate to support missions over Taiwan and points south. This might change in the unlikely event that the Japanese let us use Okinawa to defend Taiwan, or if we get new bases in the Philipines, Singapore, Malasia, or Indonesia, also highly unlikely. Our alternative is to use carriers which are now highly vulnerable to the Chinese. No wonder the Chinese think they can get away with claiming sovereigny over the South China Sea.

    Lastly, the A330 can be fitted with GenX type engines more easily than the 767. Given the long period over which these new tankers are to be delivered, that fact may prove important.

  8. Here’s an interesting article about the KC-30 from “The Australian”:

    Tankers extend RAAF’s reach to northern Asia

    OR an investment of almost $2 billion — relatively modest by defence standards — Australia is about to acquire five aircraft that will dramatically boost the capability of the defence forces, and the RAAF in particular. The aircraft are the Airbus-built multi-role tanker transports, which will give the air force unprecedented regional reach. Combining those with six airborne early warning and control aircraft plus 24 Super Hornets — as well as our ageing but upgraded 71 Classic Hornets — Australia will continue to be the dominant air power in Southeast Asia and beyond.

    The delivery is slightly late — RAAF hoped to receive the aircraft last year — mostly because of changes mutually agreed between the customer and Airbus.

    A commercial A-330 costs about $200 million, depending on configuration, so Australia seems to have boosted its combat and transport capability at a good price. In addition, the Australian companies that have undertaken the conversion work have required certification by Airbus, which means that can now win work on any Airbus aircraft, commercial or military. The capabilities of the new tankers are so great, one senior RAAF source says, “it will take us several years to learn how to fully exploit the potential of such a potent aircraft”.

  9. Aero Ninja :
    As for the Indian tanker competition, I suspect that at the very least, Airbus is more interested than they are letting on. Even though the USAF competition is for up to 179 aircraft, they could use those 6 sales if they don’t win that big one.

    Airbus was awarded this contract, before it was recinded, so both they and Boeing may believe this contract may already have been decided, even if it requires re-submission.

    • My guess is that the indian tanker competition is to a large part
      dependent on the quality of the newfound US – India “friendship”.
      The purchase will be purely politicaly motivated one.

Leave a Reply

Your email address will not be published. Required fields are marked *