Not to be argumentative but just offering my own point of view. That is correct. Same with any Tanker. I notice they are still putting an upper deck cargo door in the forward section. When it is not carrying fuel at least it can haul a decent freight load. I am thinking how much fatter the A330 fuselage is, AND how much heavier the airframe weight is versus payload percentage. That penalty would be paid every time the A/P is flown regardless.. From what I could find, the difference in fuselage diameter between the KC-135 and 707, KC-135=132", 707= 148". This is where the KC-10 comes in handy but getting the fuel to the theater cheaply isn't the entire equation. Hell, if you really want to carry bulk, tank up a C-17. Placing a couple of large tankers in a wide spread theater of operations is not logistically efficient. Airforce pilots are adamant that MORE booms at closer intervals are what is need to fight efficiently so there is bound to be a tradeoff somewhere. I think the fighting efficiency is more important than the transport aspects.(Just my opinion)
I remembered that it was smaller and Boeing knew that the 707 would need to be wider than the 132 incheds of the KC-135 or the 367-80 (707 prototype). Perhaps Bob can chime in on the real history, but the fuselage diameter of the KC-135 matched that of the earlier KC-97 and that's probably not a conincidence. The KC-97 was as big an airplane as was in the inventory at the time and I don't think the AF figured they would need anything wider.... Remember too, that they were delivering KC 135's only two years after the order was placed! Think about that for just a moment, with nothing more than slide rules and hand cranked calculators they designed, built, tested, and had in production a tanker version of the prototype that was built from no tooling at all.... If you said you could do that today anybody would laugh at you.... It's gonna take 4 or 5 years FROM WHERE THEY ARE NOW, (which is delivering a very similar airplane in low quantity production and is already years late) to get to a production tanker. Somebody there needs a good swift kick and get it done in two years... According to Wiki, the 707 got wider as a result of the demand from customers that it be an inch wider than the DC-8... I agree with you 100%. That is why more of a lower cost aircraft (the 757 based tanker) would have made a lot of sense. More booms would have made a big difference, as well as the effects of attrition. If you have more aircraft, if you lose one or two over time it doesn't hurt your capability as badly (as we will find out with our low quantity of F-22's someday).
That was back in the day when Engineers could design the entire airplane as opposed to the systems "specialists" they have now. I think with Catia and other design aids they should be able to do a fast-track design/build on this without too much trouble. After all, they have most of the hard lessons learned on the Italy/Japan tankers to refer to. Wichita started bringing in Engineers yesterday to get started. It will be interesting to see how well they do on the time line.
I don't want to get into trouble with Boeing but I will go ahead and repeat what I was a part of and witnessed in 1956. First, I'm amazed at how much the AvChatter's know about the ancient history of the KC-135/707/DC-8 fuselage war. Our group was well into the process of drawing up a huge structural assembly of the 707 with KC-135 sized fuselage frames, 132" and we got word to quit and to start over. The frames were to be 148" diameter. The 707 geometry raised the frame center 4" and the increased diameter caused a crease line in the fuselage that the KC-135 doesn't have. At the time, Douglas was out-selling us because the DC-8 fuselage was wider and would give the passengers more comfortable butt room in 6 abreast seating. The VP of Engineering at Boeing balked because it would force us to re-tool for new fuselage frames instead of using existing KC-135 tooling, also it would increase drag. So he got into a neck bowing exercise with president Bill Allen and lost. This incident was to cause the eventual ouster of the VP and he defected to Douglas. The KC-135 fuselage diameter was just fine because it had nothing to do with passenger comfort. If one looks at the profile of the 707 he will notice that the tangent point of the crown line in the fuselage is way aft of the keel line tangent point. These points are at the same station on the KC-135 and are beautifully symmetrical. I just completed a very nice 41" long profile painting of the first KC-135, 55-3118, the 367-80, and the first 707, N707PA. They are all in the same scale, 1/40th and you can see the progression of length and depth of the fuselages. They are at the photographer now being photo'd for prints. As soon as shrink one of my snapshots I will post one.
Bear with me if I got a bit over enthusiastic in my response. I am one of many who is angry at the debacle of the 787 and for once I can see a program that has a chance of being run like it should be and probably will be. I go back to a time when we did everything ourselves IN A BOEING INSTALLATION. Engineers not only created their designs but did the preliminary layouts and production drawings. It was labor intensive and hundreds of hours were spent putting it on aluminum Master Layouts and on the linen detail drawings. Then master mechanics translated it into the three dimensional product. It was done by the company in the company and controlled by the company and the product was a work of pride that had to meet strict standards. What is going on now is born by the bean counters and they should be locked in their offices to count beans. When I see good work produced by talented and dedicated people squandered by bad management it boils my blood.
Looks like it is official now as EADS has decided not to contest the decision. http://www.flightglobal.com/articles/2011/03/04/353951/eads-concedes-kc-x-contract-award-to-boeing.html
It was pretty obvious they would not. They submitted an offer with two goals: 1) They win, and BOEING has to explain to airlines worldwide why the USAF chose an AIRBUS instead of a BOEING. 2) They lose, but BOEING had to lower their price by 40% (from the 1st proposal ten years ago) which means that this military contract will not be profitable, or not as profitable as it might have been, but BOEING will have to devote a lot of resources to design, build and test the KC-46. As resources are not unlimited, this means BOEING will not have them available for the 777NG or the 737 replacement. Not only it was a win-win strategy, but they also gained a lot of karma from the USAF with whom they still have a lot of future potential business.
Wily, Obviously you have never done business with the Government. There is a three letter acronym that spells profit for anybody doing business with the U.S. DoD. Can you say ECP!!! I knew you could!!...... ECP means Engineering Change Proposal. It's a time proven method of making your money because the Government will NEVER leave the progam alone. Every time they want a change, you simply say "Yes sir, we can do that!!!" and give the customer exactly what he wants. And every change is provided on a cost plus basis. You make your money, and you make profit on the change, and if it's work that you probably would have had to do on your nickel earlier, because it's done on an ECP, the Government pays for it.... You are naive if you think that Boeing wont make big money on this program. Just in terms of how many airframes they will sell and the spare parts business for the next 40 years will be money in the bank. Add in FMS, and follow on buys of the airplane, if Boeing doesnt make a bundle on this program Ill eat 767 tanker . As far as resources goes, Boeing is doing the engineering work out of Wichita, so it wont impact the engineering in Washington. Secondly, this is a modification program. It isnt a big drag on resources like a whole new airplane. If I worked for Boeing Id be more worried about layoffs now that the 787 engineering effort is winding down. Boeing can do anything they want on the 777NG and the 737 replacement, since they will have the staff to do it. And, since the Government pays as they go, you get progress payments every month. Consequently, government programs dont require capital investment up front. And as far causing your opponent to low ball his offer, didnt Boeing do exactly that to Airbus on the A380? With the double decker 747 they pushed Airbus to have to bid so low on the A380 that that program will likely NEVER pay off for Airbus, and OBTW, while Airbus was working on the A380 the didnt have the resources to compete with Boeing on the 787, of which Boeing has murdered Airbus in that market. In the last 10 years, Boeing has outmaneuvered Airbus at each stage, and this program is no different. Boeing simply beat them again.
Solo, The KC-46 is a fixed price contract and the airplane features a brand new wing (the original one suffered from "issues with flutter of the wing pods") and brand new (787) cockpit. That's a lot of work and a lot of uncertainties. The 747-8i drove the A380 prices down, just like the A350 forced BOEING to sell over 300 787-8 well below cost. http://www.flightglobal.com/blogs/flightblogger/2010/12/the-price-of-boeings-787-sales.html Isn't competition great for the customers?
FFP contracts are the basic framework, as in the boat example above, any good contractor knows how to play the game, ECP's and ECO's ALWAYS end up making money out what seems like nothing. Well, I don't know if Boeing will make money original sales of the 787, but I'm sure that they will make money in the aftermarket. Aircraft and engine manufacturers are like crack dealers, they'll just about give the airplanes and engines to get you hooked, but when you go to buy parts you will have to pay for it like an addict..
I saw a summary of a study that recommended that: With increased maintenance, many of the KC135's can remain in service until 2040! B52, KC135... Boeing builds a helluva plane.
Solofast is right. I made more money on change orders as the Air Force and NASA can't help but make changes. Sometimes, the RFP is put out by a different group than the "end user" and when that happens, there are many change orders. Also, I think I read the contract was Fixed Price Incentive Fee, which will give Boeing a chance to make money. If the contract is like others that I have worked on, the Air Force would have also put in an Award Fee Clause. Another chance to make money.
Tcar- Many of the KC-135s will remain in service for a long time. This initial order for KC-46As in no way provides enough replacements for the KC-135s in service. Like Bob said, those aircraft were designed with slide rules and not CAD, and there was no way an engineer was going to have one of his pieces break, so they were built stout. Good engineering rules of thumb were a big help back then, and helped robustness. Taz Terry Phillips
Taz, Lots of truth in that. Now we have INFINITE element analysis that will tell you the stress in every square inch of the parts, but that's only as good as the loading and the loads are NEVER actually modeled perfectly so you have very accurate analysis based on only so so input data. At that point the experienced engineers know where to put more metal to make sure that things last, but the inexperienced engineers will believe their "greensheets" and ok the design, go off fat dumb and happy that it will be fine. There are a couple of sides to this, if we had had FEA when we designed the F100 engine we probalby would have added 2 pounds to the engine and quadrupled the life by reducing stress concentrations on a bunch of parts and the LCF issues that we found once they started cycling the engine wouldn't have happened. The other side is that now we believe the analysis way too much and try to remove every last pound of weight. The result is that, even though the stress is equal everywhere, the material isn't quite equal so it doesn't break where you expect it to, it breaks where ever it wants too and the failure isn't predictable. Isn't technology wonderful????
