Let me put it in even simpler terms. Its like saying the F-15 has a better fuel consumption than the F-16 because it is a heavier jet using ~slightly more fuel. Can't argue with the logic but only get laughed at.
Tot I put it even easier. Ferrari vs Ford. Ferrari is heavier but fuel consumption on per lb basis is lower than Ford. So Ferrari has better fuel consumption according to you whereas Ferrari actually uses more fuel per km/nm driven compared to the Ford (which is what Boeing is saying and I'm agreeing).
Uhm no. That's not my argument. My argument doesn't care which one is the heaviest or carries the most fuel. It only cares about which jet uses the least fuel to do a specific task (the fuel cost of a "pallet mile"). In this case the 330 will break even at 24 pallets no matter what config of the 767. Because it is a van compared to a sedan. the van may use more fuel, but also carries more. This is left out of your car/fighter jet analogy.
If the USAF is looking into the future and expects the typical load will be greater than 24 pallets, then the 330 should win this parameter (per the assumptions of this thread, since it may break even a lot earlier than that).
It is crude and ballparkish, but to me it seems that the USAF has a need to carry lots of cargo economically.
Quote:
Originally Posted by weasel1962
Sorry, in your case, its not even per lb. Its per pallet. So because the F-15 carries more fuel tanks, hence its fuel consumption is even lower. That's the logic I am supposed to agree to...
You are contending that a transport jet carrying pallets will reach MTOW before it bulks out when loaded?
The "pallet mile".
________________ "Of course, the whole point of a Doomsday Machine is lost, if you keep it a secret! Why didn't you tell the world, eh?"
Last edited by Grand Danois; March 21st, 2008 at 08:48 AM.
A 787 has 70% foreign parts. From what I have been able to find on the world wide web, the 767 has at least 15% foreign parts. Therefore, who knows what percentage of parts would be foreign if Boeing won the contract. At least 15% and possibly up to 70%. It all depends upon who Boeing buys the parts from. One thing is known, Boeing has been looking more overseas lately for parts. Read link: http://www.spiegel.de/international/...540438,00.html
lol. I'm not even sure you know what you're talking about.
Firstly, the bulk tanker fuel is carried in the wings. By only considering palletised cargo, you're already discounting a significant proportion of fuel load from the computation. Taking a 32/19 pallet ratio is already pseudo math not reflecting reality. We're talking tankers and you're talking cargo aircraft. I can't even consider that crude math.
What is reflecting reality is that when a plane goes on a sortie, it will use x lbs of fuel. When another plane goes on the same sortie, it will use y lbs of fuel.
Boeing is contending is that y > x where y = KC-45 and x = kc-767.
The question is simple. Do you agree with that?
I'm talking the use of the tanker as a cargo aircraft. The multirole in MRTT...
Commercial operators look at cost per passenger mile. Why should the USAF not look at pallet and passenger mileage?
I don't know why you try to divert into the tanker part.
You are letting x and y jet travel from a to b, then comparing them discounting what work has actually been done. This does not reflect the true cost per amount of work.
Underlining the importance of the cargo aspect and that the KC-45 is probably cheaper per pallet mile.
________________ "Of course, the whole point of a Doomsday Machine is lost, if you keep it a secret! Why didn't you tell the world, eh?"
Last I heard, the USAF were buying a tanker rather than a cargo aircraft. Even if we're talking about MRTT, your computation on palletised cargo would only be 1/2 the story, assuming that the cargo element is 1/2 the role.
I have not contended that the cargo role made up for ½ or a 1/3 or whatever, but I do have the observation that the cargo role is currently done by C-17 and C-5. And that is an inefficient way of transporting palletized cargo.
So perhaps it is more important in the mission complex relative to the tanker mission, than the "KC" prefix suggests.
Quote:
Originally Posted by weasel1962
Even if let's say we're talking about cargo aircraft, if your computation is based on pallet, isn't that the same as saying fuel per lb? Of course it is. You're claiming that fuel per lb is lower. That again is pseudo math as you have acknowledge. Cos neither of us know exactly how much cargo will the plane carry. Cos that's not the requirement.
You are contending that a transport jet carrying pallets will reach MTOW before it bulks out when loaded - is this so? That would be the premise for what you claim.
I agree we cannot know precisely what the USAF wants from the aircraft. But the USAF knows and made their choice.
Quote:
Originally Posted by weasel1962
Apparently, now we're not even talking about tanker aircraft. That's what you're telling me. We're talking about cargo aircraft cos I'm only allowed to look at palletised cargo? Sorry, but I don't fall for that...
Actually I see a lot of advantages of the KC-45 over the KC-767. Where they differ a lot is in the passenger/transport part, just as more fuel is carried further with less consumption of fuel per lb mile.
What caused me to respond is that the Boeing paper on fuel consumption is every bit as "pseudo" (and perhaps even selective?) as the way I lay out things here, that I see no problem with my "pseudo math". Because it is on the same qualitative level. Actually mine provide a more accurate description, as I look at cost of the work carried out, rather than looking at the fuel consumption of two jets flying from A to B. That it is not perfect evaluation, well... but it is closer to reality. If it is just A to B without taking into account what has been accomplished by doing so, then a Cessna is even cheaper.
It has to be viewed in terms of the work done. What has been accomplished...
Lastly wrt to MRTT,
Quote:
The primary mission of the KC-X will be to provide aerial refueling to United States military and coalition aircraft in the war on terrorism and other missions. However, the Air Force also intends to take full advantage of the other capabilities inherent in the platform, and make it an integral part of the Defense Transportation System.
"From addressing national security threats to supporting rapid global strikes to providing urgently needed humanitarian operations, joint and coalition operations depend upon the rapid global mobility capabilities which the Air Force aerial tanker provides," said the general.
The RFP stipulates nine primary key performance parameters:
1) Air refueling capability
2) Fuel offload and range at least as great as the KC-135
3) Compliant Communication, Navigation, Surveillance/Air Traffic Management (CNS/ATM) equipment 4) Airlift capability
5) Ability to take on fuel while airborne
6) Sufficient force protection measures
7) Ability to network into the information available in the battle space
8) Survivability measures (defensive systems, Electro-Magnetic Pulse (EMP) hardening, chemical/biological protection, etc.)
9) Provisioning for a multi-point refueling system to support Navy and allied aircraft
Ms. Payton stressed that the department has gone through a rigorous review process for KC-X and has validated the RFP accurately reflects the requirements as laid out by the warfighter.
The final RFP defines an integrated, capability-based, best-value approach. The RFP includes specific factors for assessing the capability contribution of each offeror. Along with cost and assessments of past performance and proposal risk, these factors provide the source selection authority with means to determine the best value between proposals of significantly differing capabilities and cost.
It seems the MRTT part is very important in context of the current and future overall USAF structure. Best value in contrast to the cheapest solution that makes the requirement.
________________ "Of course, the whole point of a Doomsday Machine is lost, if you keep it a secret! Why didn't you tell the world, eh?"
Last edited by Grand Danois; March 21st, 2008 at 07:26 PM.
Reason: semantics, clarity
Last I heard, the USAF were buying a tanker rather than a cargo aircraft. ...
Let's look at the decision, shall we? Last I heard, the DOD was buying next generation air-refueling aircraft. Suddenly, now it becomes MRTT. Amazing... http://www.defenselink.mil/news/news....aspx?id=49244
Nope, it's buying a MRTT, to replace existing MRTTs. The current KC-135s & KC-10s transport cargo as well as acting as tankers. The USAF wants aircraft which can carry cargo & passengers as well as refuelling, and says so, to anyone who'll listen. Transport capability is defined as a secondary need, but it's in the System Requirement Document.
Gen. Norton Schwartz, Commander U.S. Transportation Command (TRANSCOM) testified to the Senate Armed Services Subcommittee on April 4th 2006 that "What we need is a multi-mission tanker that can do both boom and basket refueling, that can do passenger lift, some cargo lift, and have defensive systems that allow the airplane to go wherever we need to take it....if we’re going to war with Iran or Korea or over Taiwan or a major scenario, the first 15 to 30 days are going to be air refueling intensive. But what I’m talking about is the global war on terrorism, sir, for the next 15 or 20 or 25 years. That is not an air refueling intensive scenario and that’s why a multi-mission airplane to me makes sense"
And in this statement dated 27-09-2007 he said "The KC-X must be a dual-mission aircraft capable of multi-point refueling, have significant cargo and passenger carrying capability, and be equipped with appropriate defensive systems. The KC-X will not only fulfill its primary refueling role, but also provide an array of enhanced mobility solutions. A tailored cargo and passenger carrying capability will multiply our transportation options and mitigate wear on the C-17 and C-5."
He said exactly the same in this statement on 21-03-2007
In view of the consistent statements by the officer in charge, & the existence of a formal requirement for the KC-X to be multi-role, perhaps you will reconsider your suggestion that it's "suddenly" become a MRTT.
BTW, both NG/Airbus & Boeing complained during the evaluation that the cargo/passenger requirement statement was too vague, so it was hard for them to know exactly what to offer. It looks as if betting on it being more rather than less significant was the right call. Perhaps NG/Airbus were paying more attention than Boeing to what the USAF was saying about what it wanted.
Last edited by swerve; March 21st, 2008 at 06:50 PM.
Link pls. Your claim is that EVERY professional who has evaluated the 2 aircraft says so. I'm sure it wouldn't be difficult to find one.
Absolute rubbish even at cost per ton of fuel. Since your claim is that EVERY professional who has evaluated the 2 aircraft says so. Link pls.
No they didn't. If you say they did, it wouldn't be difficult to find a link that says it.
Pseudo math again. Its like saying the C-5 can carry the most so ALL transport aircraft should be the C-5. I won't even bother to argue this point.
Absolute rubbish. Since you claim that published evaluations show it can use shorter runways. Show it.
Not looking for your bet. You claim EVERY professional who have evaluated the 2 aircraft disagrees with it, link pls.
Thank you for agreeing despite saying EVERY professional who has evaluated the 2 aircraft disagreeing with it.
Is that a fact? Link pls to the top speed.
Is that so? Amazing that GAO mentioned they conveniently to include that in their requirements. See my link above.
I'm getting tired of this. You supply some evidence, & so will I. You made the first claim about top speed: back it up. You made the first claim about runway length: back it up. You made the first claim about range: back it up (and remember that absolute range is irrelevant in this context - it has to be range at which useful amounts of fuel can be offloaded). Etc. You can't make unsubstantiated claims then demand that others disprove them, & call what they say "Absolute rubbish" until they do.
So far, I've provided infinitely more evidence than you, because I've provided some. Put up or shut up.
Oh, and I don't need to provide any links to prove that every professional evaluation of the two aircraft has favoured the A330. The evidence is staring you in the face. As I said - 5 evaluations, 5 selections of the A330. What more proof could you ask for?
Do you prefer traditional tanker to multi-mission tanker. If there is project
to make, choosing between short-range transmission t.ex. from
Danmark to Belgium, which one you'd thought to be better suited to
fulfill this mission requirement.
Organizational tier up to supporting role, relative conclusions, your mission
relevance is peg to these capabilities you do consider as importance.
I hope for the USAF that the decision is not overturned. I think either tanker would have worked out. I don't really care about the jobs that might be lost, because America, being the biggest economy in the world, has always been able to cope. Neither do I care about the politics. What I am concerned is that when the warfighter needs some gas, he gets it. Getting the decision blocked and redoing the tender will only do one thing => increase the probability that the guys are not going to get the gas when they need it.
