michelf…snip….such project(s) (won’t mention the infamous three lettered project here :D)… snip…
Indeed and its the project I had in mind….:D
michelfDid I correctly count 14 jet engines on the aeroplane, 4 either side of the cockpit and 3 pairs on the fusalage spine?
Those pairs on the spine are, IIRC, missiles….
The intention was to use it as a high speed missile launch platform.
Amazing photos and an brilliant concept.
michelfAnd now that they’ve gone down the learning curve? BTW how many A330s with the boom are flying now?
So all that experience with the 135 wasn’t enough to get a single point boom tanker right first time? The Japanese 767 hasn’t exactly been a brilliant problem free programme.
The A330 may not have the numbers (what there are 4 767 tankers in limited operation?) but it does work (apparently) with boom and wing pods.
Boeing will no doubt get the 767 right… but don’t use Boeing’s experience as a trump card in this.. its recent form has shown the learning curve is far from over.
michelfMy point, which you seem blind to, is that since the 767 can do the mission…and more money stays in the USA, why not buy it.
Do I need to make it any clearer?:rolleyes:
Nobody doubts the 767 could do the job..and that the US could/should favour its ‘own’…
What is less than honest is to have a competition about it…if the USAF wants the 767 and congress wants it.. just buy the damn thing and stop pretending to have ‘free and fair competition’ to get the ‘best for the warfighter’…
Buy it and say clearly.. its a US strategic asset, we want the money to stay in the US and we want to retain full control over its future… and then accept that other nations can do the same when they procure their own military hardware…
michelfAfter their performance on the A400, I would’t quite put them in the same category as Mother Theresa.:rolleyes:
Lets see.. an all new airframe allied to an all new engine being designed and built by a new company…or should we look at the development of the A310MRTT and the A330MRTT as a guide to what EADS can do in terms of evolution and development.
It might be good to look at how that programme has gone and use Boeing’s experience of the Italian and Japanese 767 tankers. One would assume, based on the experience that Boeing has in designing and developing tankers that these would have been problem free, however it has not been the case.
So looking at that then the chances of the KC-767 being late and over budget appears rather higher than that of the 330 being either…but none of us really knows…
michelfI think the point about the first Black BUck raid (as related in Vulcan 607) is that the fuelling plan barely worked and was exceptional (so it was refined each time they did it after the first raid).
its not a very reliable example to base a discussion on whether P&D is better than Boom refuelling is it?
Nobody is using it as an example of P+D being better than the boom.. but it shows that the P+D does work.. as opposed to Logan’s assertion that P+D simply doesn’t….
For large offloads (like the B-52/ Vulcan scale) it is a far more effective solution and if that is the prime mission, which for SAC is was then a boom system is ‘better’…but for TAC style missions then P+D on wing stations makes as much if not more sense….
michelfKev, common sense has very little place in the process of applying for money to build new museum space. Unfortunately function loses out to a fashion statement every time, as other museums have found out. I may be wrong, but isn’t the hangar at Newark the only lottery funded new aviation museum space (Airspace being an extension of an existing structure) that’s managed to secure funds for a building that wasn’t an architectural statement?
Not quite hitting the target there….the scale of the application (in £ terms) does play a major part in the criteria used. So the criteria for the AAM were different than for Newark…. to say nothing of the time difference between them.
You may also take into account the need the IWM had of raising matching funding from private/ corporate donors for this memorial to the US airmen. People like Georgia Frontiere would have been less impressed with a ‘hanger’…and that the USAF Museum would not have allocated an SR to the IWM had its home been the Super Hanger…
Certainly the fund raising that was done was because a private individual (Georgia) thought the building was a ‘fitting tribute’ to those who gave their lives. Without this the IWM would not have been able to build anything for the American collection, at least not for the moment.
On the one hand I can appreciate that the people assessing funding applications aren’t necessarily au fait with the future demands of aviation museum space and they have a desire to create “landmarks” with the money they hand out. However, I feel that the balance of style over function tipped so very far towards style with the new building at Cosford and with the AAM at Duxford. Both are striking buildings but neither provides any real flexibility for change – just look at the expense of installing the Liberator.
Based on the AAM the evaluation used the brief developed by the IWM…allied to achieving the museuographical/ curatorial standards expected of a national collection as well as financial criteria and yes the ‘publicity’ value as part of its evaluation. They were the ones who let the IWM ‘set’ the standard for the type of space that aviation museum could create…no AAM = no Cosford, no Milestones of Flight (no loss there), no glass wall to the BoB..no Newark funding…
The point you make about style over function is interesting. But it is heavily biased by what you think is ‘function’; which is/ was clearly not the view of the IWM. First off its a memorial, not just an aircraft museum..it had to create a new and unique visual link between the exhibition space and the active airfield, allowing active aircraft to be seen from the greatest possible number of places within the collection. That set a few key parameters for the basic concept, functions that no previous display space need to take into account.
Its form is simply the tighest possible skin that can enclose the volume required by the airframes that the iWM wanted to include in the AAM. A ‘box’ would have created space that was simply not required…it was therefore ‘wasted’ space. The material was the lowest cost (both capital and operational) envelope to keep the water out and the climate in for medium term preservation…(the lack of heating/ cooling/ humidity control initially was due to shortfalls in the initial fund raising). A steel hanger, like the Superhanger would have been more expensive.
The AAM’s form, material etc is a very rational, logical and sensible solution to the challenge set by the IWM.. it is however not necessarily the ‘obvious one’ but that does not diminish its ‘sensible and functional’ nature.
Remember also that none of the individual airframes in the AAM are of unique historical interest (save the SR which is a record setter)…they are representative ones…This permits a different approach to the preservation/ conservation issue. Thus the large south facing glass wall and associated UV is not as relevant,, a repaint is not ‘damaging’… temperature fluctuations are less damaging.. certainly if the designed cooling is installed it would be greatly diminished.. although the dehumdification has helped this as well.
As for the cost of dismantling the glass wall; the need (i.e. how often did they envisage changing the display) to allow such large movements was established by the IWM, and the comparison between the capital cost of creating an opening large enough for something like the Liberator (note also that the SR was installed, others rehung, a new entrance door installed, an additional door in the glass wall, an second handrail installed to meet the new DDA legislation (not required when Building control signed the building off), refinishing the ramp, repainting the floor and walls was done at the same time….) versus dismantling the wall within the first 5 years and again 10 years later favoured the solution that was actually designed and built.
As for change/ flexibility.. I guess that being able to bring in and rehang airframes such as the T33 or in the future the F105 through the doors is not enough?
It would be interesting to see which other large airframes the IWM could reasonably and rationally acquire that would fit into the AAM collection… (the F-14 was not acquired because it was not really relevant to the US Forces in the UK…).. an F-16.. fits…A-10..got one, F-111, got one, F-15.. got one and deliberately not installed as it serves a greater purpose whilst outside.. F-5…fits, C-130? KC-135? Neither of which were discussed as potential exhibits…a B-47 would be nice.. but are there any around to acquire…no need for a P-47, P-51, C-47. So I think the IWM got it about right…a churn after 5 years years and perhaps one in another 10…if needed.
I’m not sure that this situation is likely to change anytime soon. I know of at least one very well thought-out application that was refused on the basis that it simply catered for the needs of the museum and integrated well with its existing buildings without making any bold “architectural statements”. It’s a case of falling into line or doing without the lottery handouts under the current regime.
There you are quite correct. The Lottery is for ‘exceptional’ development…and sadly it depends on what else is in the running at the time. The AAM was alone in asking for funding at the time….now the competition is far greater simply because more people/ organisations are applying for funding. Being good is no longer enough.
But going back to the thread title…the role of the Director of the Museum in establishing the overall tone and vision for the collection is crucial… Duxford would not be where it is without Ted Inman’s passion of the museum…it would be different….perhaps better for some, worse for others…nor would Cosford have the Cold War building without Dr Fopp….other areas may not have been ‘let go’ as much, but again can everyone be pleased all the time?
michelfNo it doesn’t. I said this earlier in my post if you’d cared to read it.
That’s sarcasm in the above quote, obviously. This:
Is the military equivalent of “There, I Fixed It”. It’s like saying, “there’s nothing wrong with my refueling method, see?” When, in fact, it’s pointing out the exact opposite. If your refueling method transfers so little gas that you need that many tankers to support one bomber–even at that range–then you clearly have a problem and could only send a couple planes on such a bombing mission. It was a bottleneck at the tankers that the RAF gave itself by staying wed to P&D.
Ten years earlier, the US put up 78 bombers IN A SINGLE RAID from Guam to Vietnam–not an inconsiderable distance–and it didn’t require 585 tankers to get the job done. Why? Boom refueling.
Cheers,
Logan
You are perhaps grasping the wrong end of the issue. It has to do with the number of lbs offloaded at the distance from base, not the method of achieving that…no?
If you have a tanker that can offload 100,000lbs of gas at 5,000 miles from base you have that amount to offload, regardless of the method; if you have a tanker that can offload 10,000lbs at 5,000miles you need 10 tankers to have the same offload.. boom or P+D..or does the boom somehow allow you to increase the lbs offloaded in total?
So lets look at the issue again. Would a boom equipped tanker fleet able to offload the same number of lbs of fuel at the same distance as the Victor fleet have need fewer, more or the same number of tankers as a P+D equipped fleet?
If we think about that then the answer is that its the same number of tankers as its the total offload required.. not the method that determines the number of tankers.
Had VC-10 or L1011 tankers been on line at the time the total number would have been different.
(In your Vietnam example if KC-10s had been rather than 135s been used then the number would have been different again…)
For high lbs off load then booms are more efficient, but that is not the same as saying that P+D does not work, when clearly it does.
michelf.In the end, it comes down to “different strokes for different folks”. A C-5 or a B-2 is a much different aircraft than a Tornado or MiG-29, so I don’t expect many non-USAF types to understand the needs of the USAF in refueling aircraft that need to fly an 8,000 mile non-stop mission with a heavily loaded 4-8 engined aircraft. Probe & drogue simply won’t do. On the other hand, boom does well refueling fast jets. If the USAF’s focus is on large aircraft and fast jets, then boom is the answer.
When I read this and remember the Black Buck missions I realise that the US-centric view is blinding many; a strategic bomber refuelled by P+D carrying out the longest ever bombing mission (at the time) …and to state ‘Probe and drogue simply won’t do’ is incorrect and undermines everything the writer says. Clearly ‘probe and drogue does do’….as it does for refueling fast jets or is the USN in some way unqualified in this department (setting aside any US versus other debates)….
Neither system is perfect; both have advantages and disadvantages and intelligent mission planning can maximise advantages and minimise disadvantages inherent in both systems.
michelfThe F-104…..
was cost a effective solution for many air forces ( although not so much for U.S. who wanted longer range ), and the reason so many were sold.
Hmm… I think Lockheed’s approach to financial affairs may have been more responsible for sales of the 104 in Europe at the time than the performance of the airframe itself.
As Over G says… ‘scammed’
It was fine for its intended USAF role…with the usual limits, but it was not as good as its sales imply.
michelfGood bye and thank you Bill..
Your Observer’s Book of Aircraft was a great catalyst for my interest in aircraft.. both professional and personal.
RIP
michelfNONE of that is Boeing questioning the NEED for 1200 gal/min. It IS Boeing questioning why 1200 gal/min rather than some other number.
If Boeing could offload 1200gpm it would not ask any questions..
We know it can’t and hence the question as to why that figure at all…
Yes you ARE missing the point. To get maximum fuel offload with the KC-767 requires LESS weight (ACN/PCN) & LESS runway than to get maximum fuel offload with the KC-30. AND because the KC-767 isn’t SO big & heavy it is not so limited by the EXISTING infrastructure where as the KC-30 IS so big as to REQUIRE infrastructure improvement even to do the job as well as the KC-135R.
Here you are getting lost…
1) The 767 max fuel offload is less than that of the -30 so comparing max to max is not correct…
2) Compare like with like;- say actual lbs to be off loaded.
3) Is the increased ACN a limiting factor at the matching offload weights to the extent defined in the reports you have read and use as justification. I.e. that at max MTOW the -30 ACN being greater than 50 limits the number of austere bases that the tanker can use.
As the actual ACN may remain (at comparable fuel offload weights) below this magic 50 then that arguement reduces in importance..
The ACN issue is important at both max ACN but far more important at operational weights and hence ACNs.
That is a BAD thing as it comes with ~80,000 lbs (~43.2%) greater empty weight, 34′ 5″ (~21.6%) greater length & 41′ 9″ (~26.7%) greater wingspan. ESPECIALLY since the KC-767 is bigger & heavier than needed.
Agreed the -30 is damn big.. and agreed the 767 is bigger and heavier than needed…(at last!)
That with a full load of fuel the KC-767 (AT or non-AT) is well below its MTOW so an airfield does not even have to be capable of supporting the KC-767 at MTOW in order to get full fuel load capability…
I thought the historical off load was well below the full fuel load. Any airfield can lay claim to reduced MTOW operations…if you herald that as an example then a -30 operating at comparable off load figures can operate at many other places it cannot at MTOW…
You appear to triumph this below MTOW max fuel load as an advantage, yet fail to see that the -30 can operate at below MTOW if the mission/ airfield require it…
Was not my point BUT there are lots of thing that can be done with that weight margin
No, that the 767 has plenty of payload/lifting capacity to spare for what ever you want to do with it…
In other words, loading up the 767 with a full load of 202,000 lbs of fuel DOES NOT MAX OUT its payload/lifting capacity. THINK what happens to the flight performance of an aircraft when operating at lower take-off weight. :)…
Now we are getting somewhere..
Its capacity that can be used.. not always, not often but its there…
You now see it as an advantage in the 767 yet decry the same flexibility in the -30..
At all weights the 767 flight performance is… shall we say less than sparkling…
Which is unecessary & will be unitilized the VAST MAJORITY of the time AND comes at the cost of ~80,000 lbs (~43.2%) greater empty weight, 34′ 5″ (~21.6%) greater length & 41′ 9″ (~26.7%) greater wingspan.
Agreed… but then the vast majority of the time the 767’s max capability is not used…so we can say its unnecessary.. as is its MTOW in excess of full fuel load…
So this capacity you say in one line is handy for other things is now unnecessary for the majority of the time…
The issue is that both 767 and 30 will change USAF tanking and support operations because of their capacity over and above tanking…that capacity will be used…so how much to have…
That in order to get the max fuel offload with the KC-767 requires an airfield able to operate its ~385,000/390,000 lbs take-off weight (NOT MTOW), 159′ 2″ length & 156′ 1″ wingspan. In order to get the max fuel offload with the KC-30 requires an airfield able to operate its ~511,000 lbs (~32.7/31.0% greater) take-off weight (VERY near its MTOW), 193′ 7″ (~21.6% greater) length & 197′ 10″ (~26.7% greater) wingspan. Even to get similar fuel offload as the KC-767 requires an airfield able to operate the 193′ 7″ (~21.6% greater) length & 197′ 10″ (~26.7% greater) wingspan KC-30 at ~475,000 lbs (~23.4/21.8% greater) take-off weight..
Measuring max versus max is really unfair to the 767..as the missions it can do at that end of the spectrum are overshadowed by the 30..
Use an off load figure and then re-run….
Agreed the actual airframe dimensions are bigger and this will alter how the airbases are used from the current USAF model. Looking simply at quoted dimesions for headline effect misses the important aspects of track, wheelbase, turing radii and clearance issues that are as important… oh and balanced field length..;)
No, as already pointed out, the KC-767 can operate with a full load of fuel from a ~9,000′ runway, for the KC-30 to operate with a full load of fuel requires a ~11,000′ runway…..
And the -30 is 101,000lbs heavier and has 40,000lbs+ more fuel on board.. so it should need a greater runway…
Apples to apples…
Why yes I DO understand what drives the ability of a particular airframe to operate from a particular field. Size (footprint) & weight (ACN/PCN) – note that runway performance is related to weight (ACN/PCN)…
Clearly you don’t..
ACN is a function of the aircraft’s weight; wheel number and configuration, tyre pressures.
Foot print is to do with the aircraft’s actual size plus a percentage based operating area. Use an actual figure based operating area and the same a/c can have two different footprints…
PCN is based on the actual physical materials under and in the operating surface, plus a CHOICE by the owner/ operator as to how much maintenace they are prepared to do to that surface….not to a ‘weight’…
Runway performance is based on power, braking ability and weight….the 767 falls far behind on braking ability, hence its relatively poor balanced field performance and power…
Are you really that easily concused? What you just posted makes no sense.
Ok…
At max MTOW the -30 ACN is in excess of this ’50’ value that has been used in the reports you quote…(Just a side note… PCN’s are normally odd numbers.. hence either a 49 or 51 figure for the PCN and hence ACN would be more appropriate.)
However we know, as the historical data you have quoted, that actual mission weights involve far less fuel off load than the max even of the 135R…
So if we use actual fuel off load figures as a guide and apply then to the -30 its operating weight falls far below its max.. hence a reduced ACN.
In the reports you have quoted, which give a high number of fields the USAF may want to use that are unable to accept an aircraft with an ACN greater than 50, this high ACN is used to illustrate how limiting this ACN is in terms of future deployment.
Looking simply at max ACN then it is correct. If we use realistic ACN’s based on the actual mission parameters then the -30 will operate more often below its max ACN…and hence the number of airfields that are unable to operate the -30 reduces…opening up a greater number of bases suitable for deployment. This seriously erodes what is percieved as a 767 advantage.
Does that clear this up?
Care to try that again? I have never said anything of the sort..
You are right ‘you’ did not say it.. you repeated the words others have played…
No.
KC-767
1. With a ful load of fule the KC-767 has not maxed out its payload/lifting capacity.
2. The KC-767 requires a ~9,000′ runway in order to take-off with a full fuel load.
3. EXACTLY! Which means that the KC-767 meets the KC-X OBJECTIVE/NON-MANDATORY runway/fuel offload requirement.KC-30
1. With a ful load of fule the KC-30 has essentially maxed out its payload/lifting capacity.
2. The KC-730 requires a ~11,000′ runway in order to take-off with a full fuel load.
3. Yes.#1
Thats right. The fuel offload at range requirement is to match of exceed that of the KC-135R from a 10,000′ runway. Matching said capability from a 10,000 runway being the THRESHOLD/MANDATORY requirement & matching said capability from a 7,000 runway being the OBJECTIVE/NON-MANDATORY requirement.
The KC-135R already has MORE fuel offload at range capability (from a 10,000′ runway) than has been historically needed. But remember all the whining & moaning when the tanker lease fuel offload at range requirement was less than that of the KC-135R? So even though we DON’T REALLY NEED even the KC-135R’s fuel offload at range capability POLOTICS demands that the KC-X rfuel offload at range requirement be at least that of the KC-135R.
..
Interesting twists and turns here…
1) Max fuel capacity has little to do with actual fuel offload requirements..as defined by the historical data…
2) Politics are driving certain performance requirements.. not operational reasons..
3) If even the 135R has excess fulel capacity…then the replacement, if that is really what it is, should be in the same area.. not in excess of it..as both the 767 and -30 are…
4) Unless as you have admitted politics is playing a driving role in performance….
5) Boeing is limiting its published fuel capacity to what it thinks is needed.. not what it can do. .nor what may give greater future flexibility.. but for political reasons (to say nothing of actual aircraft performance reasons…)
6) Its about matching objectives… which may or may not be relevant to actual operational requirements but are set by political criteria…
Psst…for KC-X Boeing has INCREASED the 767’s fuel capacity. And as pretty much everyone is speculating to the same as that of the KC-135R.
..
Its a tanker.. not an airliner.. increasing its fuel capacity is a bit of a no brainer…but limiting its full fuel capacity to less than MTOW raises a bit more than passing concern….why would it do that I wonder? If its a good tanker then max full= max MOTW. We know that max fuel is far greater than anything hisotrically needed, so allow the full spectrum of max fuel/ zero freight to all freight to be avaliable… unless there is an a/c performance issue at MTOW in its primary role..
As I have said before, the KC-767 is more tanker than necessary for KC-X. BUT given how much emphasis is being placed on airlift capability I would not go so far as to say it is too big…
The KC-30 OTOH is BIGGER & HEAVIER than the KC-10 but 110,000 lbs short of the KC-10 in fuel capacity. It is a large tanker without large tanker fuel capacity.
Agreed.
…
Again a lot of twists and turns..
We agree the 767 is more tanker than is needed for the KC-X mission..
We could argue that as a tanker its too big…
The airlift is a consideration in addition to tanking…and in this role the 767 is bigger than a 135.. but far less capable than a -30….
So it does the tanking mission less well than a smaller unit and the airlift less well than a -30….
Looks like its a a second rater in both roles…
The -30 is a better airlifter and a more flexible tanker. The downsides are actual size and weight…but how limiting that actually is in operational situations is far less clear..
The KC-767. It is the only one of the two with the potential to get the job done without BILLIONS OF DOLLARS in infrastructure imporvement. Plus because of its relative closeness in size to the C-135/707, the 767 has the potential to be the platform to replace all current C-135/707 based systems. And it leeves plenty of ‘room’ for a 777-200 or A350-900 based KC-Y.
…
Your assumption is that the KC-Y will happen…
If it does then great. Chances are it will not for another decade or more…becuase of the KC-X procurement debacle (not the fault of either airframe).
So the KC-X will need to assume more of the KC-10 missions as this fllet ages and more airlift missions…
The USAF knows this is a possibility…and is planning accordingly.
No, THE QUESTION is which of the two most closely matches the requirements & which will have the lowest TLCC…
That is the obvious question…which permits you to argue details.. when the actual reality is playing in the background…
michelfThus why Boeing guestion WHY 1200 gal/min was the chose number rather than something HIGHER.
BOEING HAS NOT QUESTIONED THE NEED FOR 1200 gal/min! It has HAS questioned WHY 1200 gal/min was chosen and pointed its inconsistency with the the explination give as to why.
Interesting point of view…
1) The criteria is given.
2) We know, from Boeing itself and the USAF that the 1200 gpm figure is in excess of the known data on both the 5th and 6th generation Boeing boom.
3) This figures applies to a very limited number of ac in the USAF inventory.. which were already present in the fleet at the time of both previous solitcitations.
40 Boeing asks a question as to why this figure.. or higher…makes no difference.
5) Is dissatisfied with the answer..
And from that you do not understand that it has questionned the need for 1200 gpm.. it has recieved an answer and is unhappy with it… ho hum..
You are missing the point. THE KC-767 DOES NOT REQUIRE RUNWAY LENGTHENING! It MEETS THE OBJECTIVE of offload as much or more from a 7,000′ runway than the KC-135R can from 10,000′. In the 1st two rounds it was CLEAR that exceeding the other offer is NOT desirable & in the 3rd it is only ‘relevant or desirable’ IF the offers are within 1% of each other in adjusted price.
Not missing the point at all; merely stating, rightly, that the KC-30’s performance offers flexibility and additional capacity and capability from the same piece of runway. There are other pay offs of course..
The measure of the value of that and how one wishes to pay for it are entirely artificial measures, suited to a certain agenda…nothing wrong with that..
KC-30: 513,000 lbs
KC-767AT: 412,000 lbs
non-AT KC-767: 395,000 lbs
So potentially 101,000lbs greater MTOW…
BUT for BOTH the KC-767AT & non-AT KC-767, a full load of 202,000 lbs is still BELOW its MTOW where as the KC-30 with a full load of 246,000 lbs is essentially at its MTOW.
So your point is?
Other than even with a full fuel load the 76 could carry additional freight…
Or are you saying that the 767 as a pure tanker is under-designed as clearly it could have additional fuel load…because its below its potentially certified MTOW?
And the full load of the -30 is 44,000lbs greater.. potentially…
In order to get MAXIMUM FUEL LOAD (202,000 lbs at take-off) from the non-AT KC-767 requires ‘just’ ~385,000 lbs take-off weight. For the KC-767AT ~390,000 lbs. BUT for the KC-30 to get MAXIMUM FUEL LOAD (246,000 lbs at take-off) requires ~511,000 lbs take-off weight.
Again your point being?
That a bigger a/c with a greater fuel load is heavier than a smaller one with a smaller fuel load.. yet that smaller tanker requires a longer balanced field length….
Do you SERIOUSLY not understand how much ‘easier’ it is for a small airfiled to operate ~385,000-390,000 lbs take-off weight vs ~511,000 lbs take-off weight? By the way, with ‘just’ 202,000 lbs of fuel at take-off (which WOULD NOT be enough to match the fuel offload of the KC-767) the KC-30 would be ~467,000 lbs take-off weight.
Perhaps airfield design and construction is one of your specialist subjects..?
‘Small’… as in? Mildenhall? Fairford?
But again, spinning this to your historical data and the use of traditionally much smaller fuel loads does the max capacity have a determining factor…or do YOU not understand what drives the ability of a particular airframe to operate from a particular field?
For ANY given weight of payload, the KC-767 has a lower ACN than the KC-30.
As it should.. however the runway from which they both operate will retain its PCN value.. so your arguement that a certain number of airfields around the world cannot operate the -30 at an ACN in excess of 50 becomes moot when the real world/ historical data shows that to have the historical off load the -30 can operate at an ACN >50, thus bringing a number of those airfields back into the equation.
THERE ARE NO BALANCED FIELD ISSUES! BOTH MEET THE OBJECTIVE!
Right. Let’s go at your pace shall we…
1) The 767AT cannot reach its MTOW with a full fuel load
2) The 767AT can use 7000′ runway with full fuel….
3) The 767AT can fulfill the fuel offload requirements from that 7000′ runway..
We agree so far?
1) The -30 can reach its MTOW with fuel only.
2) The -30 can see a 7000′ runway at MTOW
3) The -30 can meet the off load requirements…
So lets look at the one item the 767AT cannot do.. which is reach its MTOW with a full fuel load…why is that?
1) Because Boeing have a clear view on the quantum of fuel the USAF require…and see no need to provide more…
2) Because they cannot find space for it…
3) Because they know that at MTOW the 767AT cannot use a 7000′ runway…
Now in reality if we take the historical figures that ‘fact’ is irrelevant as the quantum carried already is far greater than normally used.. but it looks pretty damn poor on the evaluation if there is a big NO in that column.
So a very easy, clean way to deal with it is to reduce the max fuel uplift to ensure it does reach the balanced field performance….and hey presto you can look good and even better say you are not even reaching MTOW with full fuel…
Now the reality is that both the -30 and 767 are too big as KC-Xs…but as they are the only current game in hand the USAF is stuck between a rock and a hard place.
The current economic climate means that the KC-X will happen, but the follow on programmes are being poisoned, perhaps terminally by this selection process.
With that in mind….which airframe has the most potential?
Therein lies the real question…not the explicit KPPs and other static in the RFP…
michelfWhy you are wrong has already been established. I just did not feel like repeating it.
What that the Japanese 767s are operational?.. but oh.. no pods..
That the Italian ones are.. oh no.. why because they have been struggling with the pod integration? Plus other issues…
This from a company with 50 years of experience, which according to you brings a reduction in risk.
It would support the notion that its a normal process and that Boeing are doing a good job… but when its rammed down people’s throats that Beoing are a low risk option these issues become less than impressive.
That the KC-30s are already ready cleared for centre line boom and hose ops.. as well as the wings pods..
Could you perhaps tell us after how many years of flight test the Japanese 767 have reached IOC.. and after how many years the Italian ones will reach IOC…
Wrong again. Boeing pointed out that there ARE current USAF recievers which can receive MORE than 1200 gal/min – hence the inconsistancy with the explination as to why 1200 gal/min was chosen.
Let’s assume that there are receivers that can accept more than 120gpm… they were present in the inventory in the first round (no 1200 gpm requirement) they were in the inventory in the second round.. (again no 1200 gpm requirement). So questionning its appearance is logical… doubly so when you, as a tenderer know its a requirement you do not currently meet… but hey.. you know best.
YOU WORDS…”Boeing are questionning the need for a 1200 gpm rate“…
Are you able to understand English.. questionning the need…are the words.. not ‘asking for a reduction’…
BS. The KC-767 can offload MORE fuel than required from a 7,000′ runway. A KC-767 with a full load of 202,000 lbs of fuel is well below its MTOW.
As I said.. the KPP can be matched and exceeded….the KC-30 can do even more…it might be relevant or desirable.. or not…but its not BS..
Err…According to CSI Inc/EADS NA the KC-30 requires a 11,000′ runway to operate at MTOW, the KC-767 ‘only’ 9,000′. 🙂
And the MTOW of the KC-30 is what? Compared to that of the 767.. Try to keep up and compare apples to apples…
And in order to reduce its ACN, the KC-30 has to operate at reduced take-off weight. That means LESS PAYLOAD (fuel). As already pointed out, at a ACN/PCN of ~50 the KC-767 can actually offlroad MORE fuel at range than the KC-30.
Oh.. old chestnuts again.. you have banged on about how little fuel is offloaded historically, illustrating that even 135s often do not approach MTOW…so historically is entirely probable that both 767 and -30 will operated below MTOW.
Or to be a tad more rigorous compare ACNs at comparable weights.. either in terms of actual lbs… or percentage of MTOW or even, perish the thought in terms of actual lbs of fuel off loadable at the planned distance, based on actual mission data.
You will find.. or not as the case may be, that this alters the ACN/PCN issue….Thus balanced field issues are a more problematic issue than ACN/ PCN ones…once you compare apples to apples.
michelfWrong.
But of course.. your arguements and points are so credible..so well researched and presented.. or in your own words BS….
Boeing hasn’t questioned the need for 1200 gal/min. It has questiond WHY the change & the inconsistency of the explination for the change. IT HAS NOT ASKED FOR THE RERQUIREMENT TO BE REDUCED.
Boeing has questionned the 1200 gpm. .because its in excess of ANY current USAF reciever…hence the “Why the change?” Question and it was not ‘convinced’ by the answer.. fine..
But where the the blublazes do you get the notion that I said they asked for a change, let alone a reduction.. other than one of your Olympic standard leaps of imagination…
Quite the opposite.
The opposite of what? Did you do the design studies that look at airfield infrastructure? And the implications of different types of aircraft that use them? If so then be clear…
The KC-767 DOES NOT REQUIRE runway lengthening. It EXCEEDS the KC-X runway/fuel offload requirements. In fact as runway lengths get shorter, the difference between the KC-767 & the KC-30 is REDUCED. Not to mention the fact that airfields with shorter runways generally have lower PCN (BOTH the RAND AOA & the CSI Inc./EADS NA study say that at a PCN of ~50 or less the KC-767 actually has greater fuel offload at range than the KC-30). And because the KC-767 can actulaly operate from much of the existing infrastructure, it requires comparatively little infrastructure improvement.
Lets look at the USAF’s largest tanking base in Europe, Mildenhall.
We can assume, using historical data (your favourite) that tanking operations will continue from this base… Using historical data the 767 can replace the 135 as required…. (and exceed the KP thresholds).
But look a bit more… it becomes runway limited before it become payload limited.
In order to meet the balanced field requirements the runway at Mildenhall would need to be extended..as it approaches its MTOW load…
Now if this were a TDY location then such compromises would be accepted, perhaps less acceptable for the European USAF tanker hub…Its a matter of perception..
The KC-30 on the other hand is not limited by the runway length to carry its full fuel load….and can use the existing infrastructure as it stands.
In order to get the same number of airframes with the USAF standard spacing on the ramps some extensions are needed… the USAF standards are different to the ones used for civil aircraft operation… generally greater…
Also at Mildenhall the airside infrastructure extensions are possible.. runway extensions, regardless of cost, are improbable….but you know better no doubt…
The KC-30 OTOH, despite its good runway performance (big aircraft with comparatively poor lifting/payload capability – I.E low MTOW for its size) is SO much bigger & heavier (bigger & heavier than every aircraft in the US inventory except for the C-5s & a few 747s) that it requires MAJOR infrastructure improvement.
ACN depends of the actual load of the aircraft…there are max and min values and interpolation between the two in proportion to the actual weight of the aircraft is standard..
So.. according to your historical data the KC-30 will be operating below its MTOW and hence at an ACN number below the value of the C-5 and 747…whilst when needed it can carry a bigger ACN.. even in excess of the PCN if the number if uses fits within the operating regime established for that airfield… The PCN is not an absolute..it is dependent on the maintenance regime demanded of the infrastructure..
So…. in order to use the max capability of the 767 runway extensions are the prime infrastructure improvement required… if a compromise is accepted then fine… KPP thresholds are met and exceeded…great…
In order to use the max capability of the -30airside infrastructure needs work and hangers need to be replaced…but the max capacity is far greater… KPP thresholds are exceeded etc etc..
But please, unless you have done the airfield studies, rather than just read them, allow others to have a very different view from yours.. that is not BS…
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