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More KC-46A woes....

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More KC-46A woes....

Old 16th Jan 2019, 22:42
  #721 (permalink)  
 
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Ken - May I remind you of basic Internet etiquette: ALL CAPS is shouting. Please stop.

You're right about one thing. Boeing underbid on the initial contract. But let's get things clear: the customer, Gawd bless him, is going to end up paying what it cost to develop the airplane, plus margin, irrespective of the initial price. Boeing will make its money back once the USAF needs support and services and Boeing owns the IP on the commercially certificated baseline aircraft,

As for whether Airbus would have incurred the same delays - we don't know. However, it does seem that a very conscious Boeing decision, post-award, to change the way the KC-46 was built has played a part in the problems. To get the cost closer to the price they'd bid, Boeing decided to build the aircraft at Everett, as the 767-2C, up to the point where the boom and pods (and other things) got bolted on, because commercial manufacture was cheaper. I believe it's been suggested here that some commercial/military standards conflicted.

Also, enough with the red herrings over the cargo floor. Previous MRTTs did not have one. However, by the time the contract for KC-X was awarded, the A330-200F had been in service for a year, so it was not exactly a risk factor.
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Old 16th Jan 2019, 23:45
  #722 (permalink)  
 
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Originally Posted by tdracer View Post
In short, yes, the KC-46 has demonstrated the ability to take off fully loaded from an 8,000 ft. on a plus 15 deg C day.
That's surprising. Not that it can take off inside 8,000 ft, but that it can actually operate from a 9,000 ft runway. The KC-767 can't do it with full fuel, nor could the variant offered to the UK.

What's the Balanced Field Length requirement with all 93 tonnes of fuel? My understanding is that it needs a longer runway than a 330 MRTT with 111 tonnes of fuel.
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Old 17th Jan 2019, 01:33
  #723 (permalink)  
 
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Originally Posted by Jackonicko View Post
That's surprising. Not that it can take off inside 8,000 ft, but that it can actually operate from a 9,000 ft runway. The KC-767 can't do it with full fuel, nor could the variant offered to the UK.
Different engine, more thrust, lighter airframe (KC-46 is based on a 767-200, the others listed are -300)

Edited to add:
The 767 tanker proposed to the UK was using ex BA 767s powered by the RB211-524H. Quite frankly, the Rolls 767 was a dog - heavier engine, poor TO performance, lousy fuel burn - the engine simply wasn't a good match to the airframe (there was a reason why only 40 were built, compared to the several hundred each for both the PW4000 and the CF6-80C2). I suspect some of the negativity aimed at the KC-46 from the other side of the pond is based on the crappy specs of the proposed Rolls powered UK tankers.

Last edited by tdracer; 17th Jan 2019 at 02:28.
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Old 17th Jan 2019, 02:08
  #724 (permalink)  
 
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An awful lot of data on 767 and models can be found at

Boeing 767-200ER, Photos and Specifications
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Old 17th Jan 2019, 07:04
  #725 (permalink)  
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KC-767I is powered by the GE CF6-80C2, but I understand that even after the RW at Pratica di Mare was extended, the Italian Air Force cannot operate it with max fuel for most of the year.

Quadra-national think-tank comparison of KC-767 (not the old ex-ba aircraft the MoD was offered), A330MRTT and A310MRTT with an equal task requirement at ISA / SL / zero wind showed how poor the Boeing RW performance truly was. The RW was a level 10000ft balanced field and each aircraft was required to land with an hour's average burn to tanks dry (simulating an alternate aerodrome requirement) and the reps were required to calculate the max fuel available on take-off. The first thing the US rep said was "Can we make it 12000ft?" - which was refused. As the Boeing rep told us during FSTA times "Yes, that's where we think Airbus has us beat"...

Presumably the KC-46 has uprated engines and uprated brakes if it can really operate from an 8000ft balanced field within normal certification limits? Or was 8000ft the take-off ground roll?
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Old 17th Jan 2019, 10:35
  #726 (permalink)  
 
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Originally Posted by Bing View Post
Well in that case they can cancel the KC-46A and save all that time and money. If you write requirements that can't be met don't be surprised if it goes badly.
Oh my. Requirements that can't be met? The suggestion was made that if someone had stood up against USAF and eliminated the main deck cargo door and floor requirement they'd already be flying new tankers. That's utter tosh. Those items were ALREADY developed, tested and certified. The delays and cost increases have NOTHING to do with the cargo door and floor. But lets suppose USAF did eliminate the cargo door and floor requirement for the KC-46 because they already have hundreds of cargo door and floor equipped tankers. Those tankers will ALL be retired and then USAF will only have tankers with no main deck cargo door and floor. You might as well argue to eliminate the boom requirement. After all, USAF already has hundreds of boom equipped tankers. The delays are all due to various developmental items the no tanker anywhere has. USAF wanted those items in their new tanker because they wanted the new tanker to do much more than just pass gas or haul trash. They wanted them to be part of future fights. That's one reason the KC-46 (unlike any other tanker, including A330MRTT) is EMP hardened.
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Old 17th Jan 2019, 11:18
  #727 (permalink)  
 
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USAF wanted those items in their new tanker because they wanted the new tanker to do much more than just pass gas or haul trash.
So requirements that can't be met. Or you'd have operational KC-46As.
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Old 17th Jan 2019, 11:41
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Originally Posted by BEagle View Post
KC-767I is powered by the GE CF6-80C2, but I understand that even after the RW at Pratica di Mare was extended, the Italian Air Force cannot operate it with max fuel for most of the year.

Quadra-national think-tank comparison of KC-767 (not the old ex-ba aircraft the MoD was offered), A330MRTT and A310MRTT with an equal task requirement at ISA / SL / zero wind showed how poor the Boeing RW performance truly was. The RW was a level 10000ft balanced field and each aircraft was required to land with an hour's average burn to tanks dry (simulating an alternate aerodrome requirement) and the reps were required to calculate the max fuel available on take-off. The first thing the US rep said was "Can we make it 12000ft?" - which was refused. As the Boeing rep told us during FSTA times "Yes, that's where we think Airbus has us beat"...

Presumably the KC-46 has uprated engines and uprated brakes if it can really operate from an 8000ft balanced field within normal certification limits? Or was 8000ft the take-off ground roll?
KC-46 has uprated Pratt, not GE engines, and has a bit more wing than the KC-767 (KC-767 has a -200 wing and KC-46 has a -300 wing). And no, 8000 ft is not take off ground roll. And, oh yeah, no thrust reversers. I think the latter is foolish, but presumably the USAF planners know a quite a bit more than I do. Or maybe it has such a powerful braking system (it has the -300 brakes on a -200 fuselage) that it needs no thrust reversers, which could perhaps account for the improvement in balanced field length. I'm not familiar with those particular details. So maybe designing a "franken tanker" was really not such a bad idea after all. And on the subject of "Franken tanker", the 767C2 airframe is the 767-200LRF airframe, which mates a -200 fuselage with -300 wings, landing gear, engines, etc. So all those "franken" bits were put together and certified well before the KC-46 came into being.
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Old 17th Jan 2019, 12:07
  #729 (permalink)  
 
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Originally Posted by LowObservable View Post
You're right about one thing. Boeing underbid on the initial contract. But let's get things clear: the customer, Gawd bless him, is going to end up paying what it cost to develop the airplane, plus margin, irrespective of the initial price. Boeing will make its money back once the USAF needs support and services and Boeing owns the IP on the commercially certificated baseline aircraft,
Indeed. But such a bidding strategy requires accepting lotsa risk and deep enough pockets to defer profiitability for several years. Airbus was apparently unwilling and/or unable to do that.

As for whether Airbus would have incurred the same delays - we don't know. However, it does seem that a very conscious Boeing decision, post-award, to change the way the KC-46 was built has played a part in the problems. To get the cost closer to the price they'd bid, Boeing decided to build the aircraft at Everett, as the 767-2C, up to the point where the boom and pods (and other things) got bolted on, because commercial manufacture was cheaper. I believe it's been suggested here that some commercial/military standards conflicted.
We won't ever know how Airbus would have done schedule wise, but given the track records of both Airbus and Boeing, probably, almost certainly, no better and likely worse. Unlike Airbus, Boeing's been doing military derivatives of commercial airliners for decades. Cost is a different matter. Boeing figured out how to build a military product on a commercial line on the 737 for the P-8. They applied those lessons learned to the 767 so, unlike the KC-767 and A330MRTT, the KC-46 could be built on the production line rather than completely built, flown elsewhere, and then taken apart to turn it into a tanker.

Also, enough with the red herrings over the cargo floor. Previous MRTTs did not have one. However, by the time the contract for KC-X was awarded, the A330-200F had been in service for a year, so it was not exactly a risk factor.
I agree. The main deck cargo door and floor have absolutely zero to do with Boeing's cost and schedule difficulties. ZERO. The 767C2 airframe upon which the KC-46 is built was developed, tested and certified well before the KC-46 came into being and include a cargo door and floor because it is the basis of the 767-200LRF.
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Old 17th Jan 2019, 12:27
  #730 (permalink)  
 
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At the end of the day Boeing took a commercial decision - no doubt at the highest level- to go lo-ball on a technical spec that was challenging -I'd love to know if they were warned what the risks were...

they have the income from elsewhere to be able to take the hit - the only people hurting are the shareholders - and the USAF guys waiting and waiting for their promised super gas tank...

Maybe Airbus dodged the bullet..............
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Old 17th Jan 2019, 15:14
  #731 (permalink)  
 
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" That's one reason the KC-46 (unlike any other tanker, including A330MRTT) is EMP hardened. "

KC135 and variants have been emp hardened for years and years
some hints and other related data at

https://www.govinfo.gov/content/pkg/...2hhrg71448.htm

Last edited by CONSO; 17th Jan 2019 at 15:35.
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Old 17th Jan 2019, 15:48
  #732 (permalink)  
 
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Originally Posted by melmothtw View Post
It's one thing to have KC-135s in the inventory, it's quite another to have them available for operations.
KC-135 availability and mission capability rates have held steady for more than a decade and currently stand at 65% and 80% respectively. This compares to KC-10 of 65% and 79% over the same period. To put these numbers in perspective that's more than three times better than A400M (which has been holding for some time at under 20% availability) and more than twice better than Typhoon, both of which are are much much newer than either KC-135 or KC-10. Can't speak to A400M mission capability because it's still not cleared for many of its tactical capabilities.
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Old 17th Jan 2019, 16:23
  #733 (permalink)  
 
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Originally Posted by CONSO View Post
" That's one reason the KC-46 (unlike any other tanker, including A330MRTT) is EMP hardened. "
KC135 and variants have been emp hardened for years and years
You are correct. I misspoke. More accurately, KC-135 and KC-10 while hardened, were not hardened to the levels of MIL-STD-2169. KC-46 is hardened to more then twice the level of MIL-STD-2169 (although not quite to the level of VC-25 and E-4) and has been HEMP tested per TOP 01-2-620. Further, no legacy tanker has been HEMP tested per TOP 01-2-620 for the simple reason that those tests had not been developed when those aircraft were designed and certified. I may not go into any more detail than that.
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Old 17th Jan 2019, 16:32
  #734 (permalink)  
 
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Originally Posted by Asturias56 View Post
At the end of the day Boeing took a commercial decision - no doubt at the highest level- to go lo-ball on a technical spec that was challenging -I'd love to know if they were warned what the risks were...
Boeing was well aware of the risks and put in place various measures to mitigate the risks. Not all were successful. Boeing took similar and significantly greater risks to win the MQ-25, T-X trainer, and UH-1N replacement programs. Several contractors are crying foul because none have the cash flow that Boeing's commercial airliner business generates and are consequently forever disadvantaged.

Maybe Airbus dodged the bullet..............
I personally believe they consciously did so by submitting a final bid that was essentially non compliant in addition to being significantly pricier than Boeing's. But by staying in the program they ensured Boeing would 1) have to put the KC-10 boom and some other improvements on it and 2) force them to bid low. If Airbus had not bid, the project would have been sole source and Boeing could have effectively written the contract. Strategically it was a good decision on their part even if they knew they could not compete, because it kept Boeing's feet to the fire.

Last edited by KenV; 21st Jan 2019 at 15:47.
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Old 17th Jan 2019, 17:15
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Originally Posted by KenV View Post
They applied those lessons learned to the 767 so, unlike the KC-767 and A330MRTT, the KC-46 could be built on the production line rather than completely built, flown elsewhere, and then taken apart to turn it into a tanker.
Of course the RAF surge Voyagers were built, flown elsewhere to be turned into tankers, then flown to the UK to be turned back into airliners again!
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Old 17th Jan 2019, 20:04
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Originally Posted by Davef68 View Post
Of course the RAF surge Voyagers were built, flown elsewhere to be turned into tankers, then flown to the UK to be turned back into airliners again!
Nicely done, say three days for the light bulb to come on?
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Old 17th Jan 2019, 21:37
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Originally Posted by BEagle View Post
KC-767I is powered by the GE CF6-80C2, but I understand that even after the RW at Pratica di Mare was extended, the Italian Air Force cannot operate it with max fuel for most of the year.
The PW4000 as installed on the KC-46 has over 5% more takeoff thrust than the CF6-80C2BF as installed on the KC-767.
Deleting the thrust reverser doesn't affect TO performance calculations since the FARs don't allow you to take credit for thrust reversers (real life of course is different).
EMP/HIRF hardening requirements on the KC-46 were so high that at many frequencies there were no test facilities capable of creating the required fields - much of the validation had to be by analysis because it couldn't be tested. There is so much shielding on the engine wiring that deleting the T/R was a blessing in disguise - otherwise there wouldn't have been sufficient room for the wire bundles.

Last edited by tdracer; 17th Jan 2019 at 22:29.
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Old 22nd Jan 2019, 14:04
  #738 (permalink)  
 
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Given the length and complexity of this thread (not to mention the various dead ends and red herrings) the following synopsis is provided:

No, not a single off the shelf tanker met USAF’s final RFP requirements for a new tanker. The RFP included many items which no manufacturer had ever before produced and which would require development, integration, and testing. Doing so required time and money. USAF’s budget and schedule for all this development plus delivery of the first 18 aircraft and all their maintenance documentation as well as spares and support equipment was very aggressive.

No, the A330MRTT being delivered today would not remotely meet USAF’s latest tanker requirements.

No, the KC-46 does not meet the A-10’s refueling receptacle requirements. But USAF admits that the A-10s requirements stated in their RFP (and to which Boeing worked) were in error. USAF and Boeing are working on correcting that now.

No, the vendor/manufacturer cannot tell USAF their requirements are “not necessary” or are “gold plating” or whatever and then ignore/alter those requirements.

No, neither the A330MRTT nor any legacy tanker can remotely meet USAF’s latest EMP/HERF requirements.

No, the KC-767I offered by BAE could not take off from a 9000 ft balanced airfield when fully loaded. But the KC-46 has more powerful engines, more powerful brakes, a slightly larger wing and shorter fuselage which enables it to take off fully loaded from an 8000ft runway on a plus 15C day.

No, Airbus was not the first to produce a fly-by-wire refueling boom. The DC-10 boom is fly-by-wire and entered service in the mid 70s. And an updated version of that boom is on the KC-46.

No, the main deck cargo door and floor have nothing to do with Boeing’s cost and schedule difficulties delivering the KC-46. The 767C2 airframe on which the KC-46 is based is the airframe for the 767LRF (Long Range Freighter), which was developed and certified well before KC-46 came into being and has been in production for some time.

No, Boeing’s cost over runs have not cost USAF or the taxpayers a dime. This is a firm fixed price contract and Boeing has borne all extra costs.

No, Boeing’s late delivery of KC-46 has not caused an airlift/tanker shortfall. The KC-135 and KC-10 availability rates have held steady for the past decade. Shortfalls are the result of an increase in tanking requirements, not a decrease in tanker availability.

No, Boeing did not get away with late deliveries without penalty. Although the late delivery did not result in an airlift shortfall, it did result in an increase in operational/maintenance cost to USAF to keep the legacy fleet going. USAF is computing that cost and Boeing will be penalized for those costs.

No, the KC-46 (unlike the A330MRTT) is not built as a commercial airliner, flown to a modification center, taken apart, and converted into a military tanker. Lessons learned from building the military P-8A MMA (based on 737) on a commercial production line were applied to 767, and the KC-46 is consequently built on a commercial production line in Everett. And yet meets all the Commerce Department’s Export restrictions and State Department’s Trafficking in Arms restrictions. This was one of the innovations Boeing used to meet their aggressive selling price which won them the contract.
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Old 22nd Jan 2019, 14:29
  #739 (permalink)  
 
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"This was one of the innovations Boeing used to meet their aggressive selling price which won them the contract."

Wasn't it third time around?!
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Old 22nd Jan 2019, 14:42
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Originally Posted by Octane View Post
"This was one of the innovations Boeing used to meet their aggressive selling price which won them the contract." Wasn't it third time around?!
Indeed. By the final RFP (which resembled the first RFP very little), NG could not meet USAF's very aggressive development schedule and backed out, and Airbus could not meet Boeing's very aggressive price.

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