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rayak
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  • 2 weeks later...

Rand's analysis calculates the costs of restarting production after a two-year hiatus, producing 75 "zombie" F-22s (zombie=back from the dead) between 2012 and 2016. The study concludes that the average unit cost for the 75 F-22s is $227 million, including re-start costs. The average flyaway unit cost, which exclude re-start costs, is $179 million.

Rand's Project Air Force today published a 120-page monograph titled:  Ending F-22A Production: Costs and Industrial Base Implications of Alternative Options.

http://www.flightglobal.com/blogs/the-dewline/

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  • 1 month later...

J'aimerai savoir vu que j'ai était chercher partous des chiffres mais sans trouver et bien les affrontement eurofighter vs raptor ect

Sur des photo j'ai vu un mirage 2000 qui en mode canon aligne un gripen et puis un raptor mais apparement sa doit étre confidentiel les chiffres des combats aerien pendant l'exercice au emirates.

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Pourtant j'ai posté une photo d'un F22 tirant 4 SDB en une salve ... juste avant dans ce topic http://www.air-defense.net/forum/index.php/topic,1848.msg473003.html#msg473003

Entre une photo d'un test sur un appareil de développement et ce qu'ont le droit de faire les appareils en unité il y a toujours une marge. On a plein de photo de rafale qui prouvent ce point  ;)

L'utilisation de plus de deux bombes en même temps ce sera pour la version finale de la mise à jour 3.2 en 2016 (ça passera de 2 à 8 d'un coup)

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  • 2 weeks later...

L'avion a des problèmes c'est sûr. Le programme a d'ailleurs été abandonné même si les lignes de prod restent ouvertes pour la maintenance et les pièces détachées. Je me rappelle aussi des photos sorties quelques mois après la mise en service des premiers exemplaires. Les Trap Doors des bombs bays étaient bouffées par la rouille... Même problème pour les Sièges éjectables qui prenaient la flotte par le cockpit (2010) :

Last February, the entire U.S. F-22 fleet was grounded when it was discovered that inadequate (and previously undetected) drainage in the cockpit had led to rust forming on components of the ejection seat. The problem was quickly fixed, and the F-22s returned to flight status.

This sort of thing, rust in an unexpected place, is typical of new weapons systems. While the growth of more powerful design and simulation software has greatly reduced situations like this, it still happens. The Department of Defense spends over $20 billion a year dealing with rust problems, and about a third of them are found to be preventable. One reason carrier aircraft cost so much more than similar models used only over land, is the additional rust-proofing required.

ou encore :

The manufacturers of the Air Force's newest fighter jet knew years ago that the composition of some mechanical access panels made the F-22 Raptor susceptible to corrosion. Military officials even changed the design to fix the problem.

But a decade later in a program already fraught with setbacks, the design flaw reappeared. Now, about two-thirds of the military's fleet of Raptors are suffering from corrosion, prompting the Air Force to speed up the timeline for bringing the aircraft through Hill Air Force Base for depot-level maintenance.

"So the world's most expensive, most advanced aircraft is in the shop for repairs for something simple that someone figured out a long time ago?" said Nick Schwellenbach, national security investigator for the Project On Government Oversight.

"I'd like to say I was outraged, and it is outrageous," Schwellenbach said, "but it's all too common."

The Project on Government Oversight has exposed numerous other problems with the Raptor, which costs more than $130 million per plane - and nearly three times that, when research, development and other costs are factored in.

Originally intended to be mission-ready by 1997, the Raptor has been plagued by cost overruns and delays. Billed as the most advanced fighter jet in the world, the aircraft has yet to fly a single combat mission.

It's unclear how much the corrosion issue will cost the Air Force to fix. Brig. Gen. C.D. Moore, who is leading production and sustainment efforts for the F-22 at Ohio's Wright-Patterson Air Force Base, said the "cleanup and mitigation" of already-identified corrosion problems could cost nearly a half-million dollars in labor costs alone. Corrosively resistant replacement panels - which won't be ready to install for another six months - will cost millions more to produce and the jets will have to be brought back to Hill or another maintenance center for installation - at a cost of millions more.

Moore downplayed the cost, however, noting it would be absorbed by the "overall sustainment plan" budget - which he said exists to handle unforeseen problems with the jet.

"We had already planned for 'over and above' work - you always do that," Moore said. "Every time you open up an airplane, you discover something."

But frustrating to Schwellenbach and other defense experts was the idea that this was not a problem that was simply discovered during routine maintenance - but one that had been identified and addressed in the mid 1990s.

At that time, the Raptor's development was already years behind schedule and critics in Congress, the federal Government Accountability Office and non-profit watchdog groups were beginning to complain that the stealthy Raptor - first conceived in the mid 1980s at a time when U.S. military aircraft were finding it increasingly difficult to avoid detection by Soviet radars - was an uber-expensive Cold War weapon in a post-Cold War world.

Even as the Soviet threat had diminished, however, the Air Force and the Lockheed Martin Aeronautics Company, the lead contractor for the F-22 program, continued to push to improve the plane's "low observable" qualities.

As originally conceived, the Raptor was designed to have few exposed joints and edges - a characteristic that lowered the aircraft's radar visibility. But techniques that made the plane more stealthy - for instance, filling the seams of the access panels with a soft, rubbery putty - were not always best from the standpoint of corrosion control.

Alerted to concerns that the metals, paint and other materials used in and around the panels would interact in a way that would cause severe corrosion - particularly if moisture was to seep into the seams - Col. Kenneth Merchant, now a brigadier general and vice commander at Hill's Ogden Air Logistics Center, oversaw a change in design. Merchant left his assignment in 1997 believing that the problem had been addressed by a change which included switching the metal used in the panels from aluminum to titanium. The change made the Raptor, the twin engines of which produce a chest-rumbling 35,000 pounds of thrust each, negligibly heavier. It also made the aircraft slightly more vulnerable to radar.

Moore said the decision to overrule Merchant's change came over the course of several years as engineers sought to find "the right balance" between durability, performance and low radar observability. "We thought we got it right," he said. "We understood there was a corrosion risk."

That irked Schwellenbach. "What's the point in it being more stealthy if it's in the shop?" he asked. "You can't even use it."

Phil Coyle, a senior advisor at the Center for Defense Information, observed that many of the efforts to make the F-22 more stealthy have resulted in unexpected and expensive delays.

"It's clear that maintaining stealth to the degree they were trying to do has been a problem and still is a problem," he said. Trading corrosion resistance for radar invisibility may have made sense when the U.S. military was trying to penetrate "the very tough radar defense of the Soviet Union," Coyle said. "But of course, the Soviet Union doesn't exist anymore."

For his part, Merchant said he believes everyone was acting in good faith when his change was countermanded.

"I don't believe there was anything untoward on anybody's part," Merchant said. "The people working on this are good Americans doing the best they can with the information and materials they have at the time."

He said the "good news story" was the fact that Hill was able to stand up its depot maintenance center a year ahead of schedule to address the issue.

But considering that total costs associated with bringing the Raptor into fighting shape are now hovering around $360 million per plane, longtime Raptor critic James Stevenson says he doesn't see any good story.

In all, Air Force maintainers are working on 17 access panels - as small as several inches and as large as two feet. Four of the panels on the topside of the aircraft have been found to be most susceptible to corrosion and will be replaced - at a cost of $50,000 per aircraft, not including labor.

Although the Air Force has called that work "minor structural modifications," Stevenson doesn't buy it. "Depot work is not minor, by definition," he said.

But Stevenson said he was not surprised to hear the issue being minimized. "They always refer to their problems as hiccups," he said. "It doesn't matter if it is catastrophic or minor."

Source : SLT

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Morice, encore lui  :lol: Il s'y connait en aviation mais a le chic pour détourner ses articles en prose ''antiaméricaine primaire'', voir ces autres contributions sur l'Agora.

Bon, aucun avion n'est parfait, mais entre un Rafale qui avait besoin d'un Super Etendart pour pouvoir tirer une bombe guidée, des Jaguar qui ne tirent pas la nuit, le feuilleton F-35, le V-22, le retard de l'A 400M, les ennuis moteurs de l'A380 et du B787, on peut multiplier ce type d'articles.

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