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More KC-46A woes....

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More KC-46A woes....

Old 6th Feb 2019, 17:19
  #901 (permalink)  
 
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JTO is correct. Also:

Lockheed Martin is claiming that all three versions of the F-35 Joint Strike Fighter (JSF) will have kinematic performance better than or equal to any combat-configured fourth-generation fighter. The comparison includes transonic acceleration performance versus an air-to-air configured Eurofighter Typhoon and high angle-of-attack flight performance vis-à-vis the Boeing F/A-18E/F Super Hornet.

"The F-35 is comparable or better in every one of those metrics, sometimes by a significant margin, in both air-to-air, and when we hog-up those fourth-generation fighters, for the air-to-ground mission," says Billy Flynn, a Lockheed test pilot who is responsible for flight envelope expansion activities for all three variants.


https://www.flightglobal.com/news/ar...-super-382078/

So the requirements can't be used as an excuse for the A2A performance.
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Old 21st Feb 2019, 00:43
  #902 (permalink)  
 
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Hmmmmm!!
from the BA yahoo stock site blog yesterday 19th
From the Evening Standard: Aerospace supplier Cobham took a £160 million hit on Tuesday to settle a long-running row with US planemaker Boeing over supply delays. The UK company, which has struggled in recent years, will pay £86 million compensation to the Chicago-based giant and £74 million to finish work on an aerial refuelling pod. Cobham promised to make two refuelling systems for the jets but both were delivered later than expected.
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Old 21st Feb 2019, 14:25
  #903 (permalink)  
 
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Not all doom and gloom - some further progress (an article on Flight Global).
The Boeing KC-46A Pegasus air tanker refuelled a Lockheed Martin F-35 Lightning II for the first time over California.
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Old 1st Mar 2019, 07:51
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Not all doom and gloom - some further progress (an article on Flight Global).
The Boeing KC-46A Pegasus air tanker refuelled a Lockheed Martin F-35 Lightning II for the first time over California.
One step forward, two steps back...

https://www.seattletimes.com/busines...manufacturing/
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Old 1st Mar 2019, 14:02
  #905 (permalink)  
 
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Originally Posted by Lyneham Lad View Post
I note the sun glare as the "latest" problem with the remote vision system with certain, limited, sun angles.

Was a remote vision system for the boom operator a program requirement? I realize that there would have been costs with putting a boom operator compartment in the lower belly, but it seems for about 70 years of tanker history starting with the KB-29 the "vision system" of the boom operator was working pretty well... Was this remote system deemed high risk? I am sure they will work the bugs out, but seems the challenges were not fully appreciated. Yes I know it is hard work.

Last edited by sandiego89; 1st Mar 2019 at 14:16.
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Old 4th Mar 2019, 08:12
  #906 (permalink)  
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Further to the FOD problem.....

https://www.defensenews.com/digital-...er-deliveries/

US Air Force suspends KC-46 tanker deliveries

ORLANDO, Fla. — Boeing’s deliveries of its KC-46 tanker to the U.S. Air Force have been suspended as the service investigates a series of problems with foreign object debris, its top acquisition official confirmed Friday.

Will Roper, the service’s assistant secretary for acquisition, technology and logistics, told reporters that it will likely be “some time” before the service begins accepting new tankers from Boeing.........

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Old 4th Mar 2019, 10:35
  #907 (permalink)  
 
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I once dropped a washer under the E-1 rack of a brand new E-3A, I lifted the insulation blanket to find it and ended up filling a FOD bag with all the junk that was there, I even had a choice of washers to use.
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Old 4th Mar 2019, 10:57
  #908 (permalink)  
 
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Don't the Boeing inspectors/supervisors actually inspect before stamping off a task?
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Old 4th Mar 2019, 13:55
  #909 (permalink)  
 
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FOD/Loose articles

This is not a new problem unique to Boeing. I remember a story (possibly in Air Clues) from many years ago, about a Beverley which suffered from a loud thumping noise from under the freight deck floor whenever there was turbulence. The cause could not be ascertained during its service life. When the aircraft was scrapped a 6 foot (10 foot?) length of steel scaffolding pole was discovered, which had been there since manufacture.

At about the same time another aircraft type had problems with clogged fuel filters. Eventually traced to a blanket left in a fuel tank during manufacture. But probably the prize goes to the dining room chair left in a large fuel tank (Sunderland?).
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Old 4th Mar 2019, 14:29
  #910 (permalink)  
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A foot long piece of wood was discovered in a Buccaneer which suffered a roll restriction at low level - and one of the early Tucanos was delivered with a workman's left over lunch in the back. Such was the build quality of the early Tucano that after they'd sat outside for a few days (to make sure that no Irish terrorist had left a little gift), they were all de-panelled and given thorough checks...

A VC10K2 in which we were doing an air test suffered smoke on the flight deck, so we did the relevant drill and landed. They found a rivet head in one of the cabin conditioning blowers, but weren't sure whether this was due to sabotage or error - the RAF was about to hand over to civilian-run majors at St Athan and feelings were high. So a complete search was ordered - but the only thing of note (apart from the fact that the lift rate modifier had never been connected to the stall warning system) was a BOAC silver teaspoon found nestling around the base of one of the control columns! It must have been there for years - this was a Standard VC10 which had been sold to Gulf Air by BOAC and had flown many years with them before coming home for conversion!

But Tengah Type gets the prize for the Sunderland dining room chair story!
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Old 4th Mar 2019, 14:59
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But probably the prize goes to the dining room chair left in a large fuel tank (Sunderland?).
I remember being told a number of years ago by a colleague of 'small stature' who had had to get into a Vulcan fuel tank that having done so he found a chair which must have been left from original manufacture.


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Old 4th Mar 2019, 22:40
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Tengah Type: I remember Vampires, particularly the early single seaters, being involved with accidents with alleged 'engine problems' which turned out to be fuel blockages caused by the lint trapped in the fuel tanks from the material used in manufacture.
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Old 5th Mar 2019, 08:53
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Originally Posted by BEagle View Post
A foot long piece of wood was discovered in a Buccaneer which suffered a roll restriction at low level - and one of the early Tucanos was delivered with a workman's left over lunch in the back. Such was the build quality of the early Tucano that after they'd sat outside for a few days (to make sure that no Irish terrorist had left a little gift), they were all de-panelled and given thorough checks...
Wasn't there also a little length problem, so that none of them matched when parked on the line?
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Old 5th Mar 2019, 17:37
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Originally Posted by BEagle View Post
KenV wrote:

No, the feed to the wing pods would have been adequate using the originally specified wing fuel pipe. But with the HDU supplied simultaneously (not using some 'main feed pipe' - the systems were not interconnected), the pressure drop at the pod using the original pipe would have been unacceptable. Hence a larger bore pipe would have been needed to cater for the situation. Which was a bolleaux idea anyway!
OK. But if the WARP and the HDU are not "interconnected", yet the pressure drops when both are used simultaneously, then somewhere in the system they share a common feed manifold that is not of sufficient size to feed both systems simultaneously while maintaining head pressure to both systems. That means the main feed manifold needs to be enlarged by enlarging the piping or more likely by enlarging the manifold's feed pumps.

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Old 6th Mar 2019, 07:47
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https://www.defensenews.com/air/2019...c-46-continue/

TRANSCOM working to defer KC-135 retirement as delays with KC-46 continue

WASHINGTON — U.S. Transportation Command is making preparations to push back the retirement of some KC-135 tankers due to delays in receiving the Air Force’s newest aerial refueling plane, the KC-46, the head of the command said Tuesday.

“Obviously it’s going to cost money, and when the money is put into the program that’s when we’ll know, but the intent is to retain 28 [KC-135] weapon systems beyond their currently scheduled retirement,” Gen. Stephen Lyons said during a Senate Armed Services Committee hearing..........

According to Lyons’ testimony, the Air Force intends to divest the 33-year-old KC-10, its smallest tanker fleet, while retaining a portion of the 57-year-old KC-135 inventory into the 2050s.........




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Old 14th Mar 2019, 23:52
  #916 (permalink)  
 
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And the beat down goes on - inspectors ? inspectors ? we dont need no stinkin inspectors !!


By
Ben Kesling in Washington andDoug Cameron in Chicago
March 14, 2019 3:45 p.m. ET The U.S. Air Force has lost confidence in Boeing Co.’s BA -1.02% ability to maintain quality control over a new aerial refueling tanker it is building, with a senior Pentagon official saying Thursday that it could take at least a year to rebuild trust in the program.
The tanker problems predate this week’s crash of a Boeing 737 MAX airliner being flown by Ethiopian Airlines, resulting in a global grounding of the passenger jet following an earlier crash of the same aircraft model last year.Boeing delivered the first of the KC-46A Pegasus tankers in January, more than a year late, after a series of production and design problems left the aerospace company nursing $3.5 billion in losses on the initial $4.9 billion contract.The Air Force then suspended deliveries in February after finding tools and other debris left in some jets, prompting a sharp rebuke from defense chiefs.
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Old 24th Mar 2019, 08:48
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AW&ST: http://aviationweek.com/defense/next...ely-autonomous

Next U.S. Air Force Tanker Likely Autonomous

The U.S. Air Force’s next tanker aircraft will probably be autonomous, the service’s top acquisition official says. “We can see it in the tea leaves,” said Will Roper, assistant secretary of the Air Force for acquisition, technology and logistics.

The Air Mobility Command was scheduled by the end of last year to complete a capabilities-based assessment for KC-Z, the aircraft that the Air Force wants to follow the Boeing KC-46A into production after 2027. The assessment marks the first step in the Pentagon’s process for launching a new acquisition program. It should be followed by a roughly yearlong analysis of alternatives, which generates the data used to set requirements ahead of a solicitation.

But Roper already seems convinced that KC-Z will not use a human operator on board the tanker aircraft to guide the Air Force’s required refueling boom into a receiver.

“If KC-Z isn’t autonomous, I’ll be really surprised,” Roper said. The U.S. Navy is already developing an autonomous tanker with the Boeing MQ-25A, but the Air Force’s requirements are more difficult. The MQ-25A uses only a refueling drogue, which remains stationary while receiver aircraft connect to it. The Air Force’s bombers and airlifters need a refueling system with faster off-load capacity, which can only be provided by a refueling boom.

Despite that extra complexity, Roper’s certainty on KC-Z refueling technology is rooted in the painful experience of resolving flaws in the remote vision system (RVS) of the KC-46. To break a two-year impasse, Boeing agreed to redesign the KC-46’s remote vision system to detailed new parameters developed by the Air Force Research Laboratory. The RVS now allows a human operator to steer the refueling boom into a receiver using a set of cameras. Boeing’s original design did not satisfy the Air Force, but it could not explain why. A team from the Air Force Research Laboratory then developed a set of standards for visual resolution and a desired configuration for the cameras. The knowledge gained by that team can help the Air Force move beyond human operators for the next tanker aircraft.

“In fixing the RVS we now have the knowledge in the Air Force to know how to go out and request an autonomous tanker and not just say, ‘give it to us,’ but specifically put on contract what we want to see,” Roper said.

Meanwhile, the Air Force is continuing to mature technologies for a new refueling aircraft. Newly-released budget documents show the Air Force plans to start designing a “small, pod-mounted tactical air refueling boom for future Mobility applications.” The Air Force is also continuing to assess “promising configurations for future Mobility applications,” budget documents state, with wind tunnel tests scheduled in 2020 for “practical laminar flow treatments and coatings for highly swept wings applicable to Mobility applications.”
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Old 26th Mar 2019, 15:27
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Originally Posted by weemonkey View Post
Report from Aviation week that frankentanker has a version of MCAS installed in flight control system.

Once again will P8 and wedgetail have this software/hardware installed?
The only version of 737 that has MCAS is the MAX version. Indeed the purpose of MCAS is so 737MAX behaves like 737NG. And both P-8 and Wedgetail are based on the NG platform, not MAX.


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Old 27th Mar 2019, 12:25
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To quote the AW&ST article:

Boeing’s 767-based tankers use a version of the pitch augmentation system that grounded the 737 Max 8 fleet, the manufacturer and U.S. Air Force officials say.........

Both the KC-767 and KC-46 fleets delivered to air forces in Italy, Japan and the U.S. rely on the MCAS to adjust for pitch trim changes during refueling operations.

In the 1980s, Boeing’s engineers considered using a pitch augmentation system for the commercial version of the 767, but dropped the idea after finding that vortex generators provided adequate control. By 2011, Boeing had already delivered KC-767s to Italy and Japan fitted with the first version of MCAS. The use of the system then spread as Boeing won the Air Force’s KC-46 contract in February and launched the 737 Max 8 in August.

But Boeing designed the integration on the KC-767 and KC-46 slightly differently than on the 737 Max family. The single-aisle airliner uses one angle of attack vane — either the captain’s or first officer’s — to generate the data used by the flight computer to activate the MCAS. By comparison, the KC-767 and KC-46 are designed to use two sensor inputs to feed angle of attack data, Boeing says.

Boeing spokesmen declined to elaborate on which sensor inputs are used to provide the data in the tanker design. The options include multiple angle of attack vanes and flush-mounted static ports........

The U.S. Air Force has launched a review of flight procedures for the KC-46, a spokeswoman says.......”


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Old 2nd Apr 2019, 19:13
  #920 (permalink)  
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https://www.bloomberg.com/news/artic...er-over-debris

USAF Again Halts Delivery of Boeing’s Tanker Over Debris

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