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Problem with one F-15 is a importend enough to keep the Eagles on the ground.
http://www.af.mil/news/story.asp?id=123074547
It was also on CNN website
http://www.cnn.com/2007/US/11/05/f15.gr ... index.html

Maybe somebody knows more about this accident?

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73-1664

It was all over the radio here, since it was a local plane. Pilot had a broken arm, few other injuries, but is recovering just fine. Hadn't heard about the grounding.

Does this affect the Strike Eagles too?

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Evil is evil, no matter how small.

Wish I would have seen better video of the crash site. The shot from the chopper they showed here was distant.
Looked like the bird was pretty much intact, flipped over onto her back. The tail was sticking into the air as it was still standing on the vertical fins.

Only thing I found funny in the report I read here yesterday, was that they had already determined \"Catastrophic Failure\" and had grounded the fleet, MINUS the birds that were mission essential?

So no training flights and make everything a must fly sortie huh?

Eagles have had a rough year with crashes and such.

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The only time you have too much fuel is when you're on fire.

That is the second F-15 to crash from that unit in the last six months. The first one was caused by some sort of crossover cable.

Guess if the 131st can't keep 'em (moving to Whiteman's B-2s), they aren't letting anyone have 'em!

Not sure if it was from the pilot or a witness, but I think I heard a comment that with this latest one, the nose pitched below the horizontal and the pilot couldn't regain control. Sure hope they figure it out before a life is lost.

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\"Those who hammer their guns into plows
will plow for those who do not.\"
- Thomas Jefferson

And they up in the air......where they belong.
http://www.cnn.com/2007/US/11/14/airfor ... index.html

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73-1664

Actually I am not proud of the fact that I am an Eagle guy now, but I can assure you that you are all wrong, except it was in fact catastrophic. And it grounded all F-15's not just non mission essential ones. The Navy diverted a carrier to deliver Super Hornets to Afdirtistan to cover for the Strke Eagles in theatre.

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YGBSM !

continue story
http://www.af.mil/news/story.asp?id=123078309

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73-1664

The canopy sill of the F-15 is actually the longeron. In an A & C model the cracks are just aft of the ejection eat about halfway back to the end of canopy. There are more than a couple that have large cracks. LARGE. But part of the problem seems to be with particular years. It may be the way the longerons were either forged or milled. They Boeing reps are trying to see if the trend extends to a particular off site manufacturer or or any other fault from the factory.

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YGBSM !

The E's are flying again but who knows what kind of findings/politics are going on with the C's.. At least those guys have had PLENTY of time to work out there K's by now. Hell there should be black letter intials in the 781H's at every C-Model station by now...

Ah your stoned dude and you can add one more C model to the list of busted longerons.............................mine ! I'm an F-15 guy
AAAAHHHHHHHHHHHHHHHHHHHHHH !

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YGBSM !

Things are terrible here at Robins right now...can't go into details but the list of TCTOs is CRAZY!!!

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CFT's are spooling up as you read this.

OC

Yup...and this is the latest from the newspaper here:

http://www.macon.com/197/story/216677.html

Robins team believes last snag cleared in F-15 groundings
By Gene Rector - grector@macon.com

ROBINS AIR FORCE BASE --After a tedious, highly detailed process much like crime scene investigation, Robins Air Force Base engineers believe they have cleared the last technical hurdle affecting the nation's F-15 fleet.

Older models of the supersonic fighter have been grounded three times - the latest happening Dec. 4 - following the Nov. 2 crash of a Missouri Air National Guard F-15C.

The last two stand downs have affected only the F-15 A through D models, about 450 aircraft. The newer, heavier and more robust F-15Es - 224 aircraft - were returned to flight Nov. 11.

The investigation has focused on upper cockpit longerons near the canopy area. To this point, cracks have been found in eight aircraft - all F-15Cs. Officials zeroed in on that area after eye witnesses to the crash said the jet appeared to separate immediately behind the cockpit during normal training maneuvers. The pilot ejected with only minor injuries.

Col. Stephen Niemantsverdriet, 880th Aircraft Sustainment Group commander at Robins, said cracks have been found in both the right and left upper cockpit longerons of the eight aircraft. He said 97 percent of the fleet has been inspected. Longerons are metal rails that run horizontally and hold the fuselage together.

The Warner Robins Air Logistics Center at Robins is the worldwide manager of the Air Force's F-15 fleet, providing resupply, periodic overhaul and engineering oversight for the premier, but aging air superiority weapon system.

The F-15 first entered the Air Force inventory in 1975. The latest model - the F-15E - joined the force beginning in the late 1980s. The fleet averages 25 years of service.

Robins engineers have issued eight inspection orders to flying units since early November -the latest at midnight Dec. 15 - identifying areas to be inspected and the techniques to be used.

"Based on our review and interaction with Boeing and the accident board, we believe we have captured and mitigated all the risks," Niemantsverdriet indicated. "We're just at the point of getting the airplanes flying again, although that decision will be made by Air Combat Command and other using command."

McDonnell-Douglas, the original manufacturer of the F-15, was purchased by Boeing some years ago.

A thinning of the longeron at a key stress point - possibly due to a manufacturing defect - may be the root cause of the mishap and the cracks found in the eight aircraft.

"More than likely it is a manufacturing issue and we have pulled all the Boeing material discrepancy reports," the group commander said. "So far, we have not been able to isolate it to a particular production run or series. The cracks show up in aircraft as old as 1978 and as new as 1985."

Recurring checks had not called for a review of the area in the past.

"It was a 25,000 to 100,000-hour part," the colonel stressed. "So it was not included in our depot and phase inspections. It was designed to significantly outlast the aircraft."

However, the Robins team has learned that a number of factors create additional stress on the component - a splice joint in the two-piece longeron with different material thicknesses coming together, reduced width proceeding from the joint, angle variations and changes in the canopy sill.

"So a large amount of activity occurs in that single spot," Niemantsverdriet acknowledged. "It's like a creek that narrows down, making the water flow faster."

The inspections call for a thorough review for cracks in the longeron and a check for prescribed thickness. "We're looking at a good portion of the longeron - about 30 inches - and we're checking thickness at about 90 different locations. For an aircraft to be released to fly, there must be no cracks and the thickness must meet production tolerances," he said.

If thickness issues crop up on crack-free aircraft, Boeing - at the request of Robins - will conduct fatigue life analysis to see if the aircraft can be returned to flight.

Replacement longerons will be manufactured at Robins. Niemantsverdriet said a production order has been placed for 15 with an anticipated 120-day lead time.

"We believe we can accelerate that," he said, "although one of the limiting factors will be availability of material."

The Robins commander had high praise for his engineering team, the non-destructive inspection lab on base and technicians on the center's maintenance line who have assisted with validating and verifying inspection orders before they were released to the flying units.

"My hat's off to our engineering team and the people who have given us a very significant amount of support," the colonel stressed.

The team may be able to enjoy Christmas if nothing else emerges.

"We pushed extremely hard over the weekend to issue what we believe will be the last (inspection order)," Niemantsverdriet pointed out. "They deserve kudos for all the hours they have put in that have brought us to where we are today. They've done a great job."

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Interesting read PRK..makes you wonder if 20 something years ago some tin knocker shooting rivets in St Louis noticed something..maybe an edge distance all of a sudden wasn't right or, for instance, a dash 6 rivet that had been working just fine was all of a sudden too long and shrugged it off. Guess what I'm trying to say is it's hard to fathom something that appears so insignificant can lead to catastrophic failure years later.

OC

F-15 grounding strains U.S. air defenses

By SCOTT LINDLAW, Associated Press Writer Wed Dec 26, 4:00 PM ET

FRESNO, Calif. - The grounding of hundreds of F-15s because of dangerous structural defects is straining the nation's air defense network, forcing some states to rely on their neighbors' fighter jets for protection, and Alaska to depend on the Canadian military.

The F-15 is the sole fighter at many of the 16 or so \"alert\" sites around the country, where planes and pilots stand ready to take off at a moment's notice to intercept hijacked airliners, Cessnas that wander into protected airspace, and other threats.

The Air Force grounded about 450 F-15s after one of the fighters began to break apart in the air and crashed Nov. 2 in Missouri. An Air Force investigation found \"possible fleet-wide airworthiness problems\" because of defects in the metal rails that hold the fuselage together. It is not clear when the F-15s will be allowed to fly again.

Compounding the problem created by the grounding, another fighter jet used for homeland defense, the F-16, is in high demand for Iraq operations. And the next-generation fighter, the F-22 Raptor, is only slowly replacing the aging F-15.

Military officials say they moved quickly to patch any holes in the homeland air-defense system, and they report an increase in air defense sorties in the past month, using replacement F-16s. But they acknowledge difficulties.

\"When you're filling in, obviously it's going to cause some strain,\" said Mike Strickler, a spokesman with North American Aerospace Defense Command, or NORAD, which is operated by the U.S. and Canada. \"You're spreading resources a little thinner than we would like.\"

But air defenses have not been compromised, Strickler said. \"We can be anywhere at any time,\" he said.

With the F-15s in Massachusetts out of commission, the Vermont Air National Guard is covering the whole Northeast. The Minnesota Air National Guard is manning sites in Hawaii. In Louisiana, the Illinois Air National Guard has been filling in.

And with Oregon's fighters grounded, the California Air National Guard is standing watch for the entire West Coast, an area of more than 300,000 square miles that is home to more than 46 million people in California, Oregon, Washington, and slices of Arizona and Nevada.

The California Air National Guard said this is first time in history that a single state's fighter wing is providing coverage for an entire coast.

The California Guard is keeping three alert sites — in Riverside and Fresno, Calif., and Portland, Ore. — equipped and staffed with pilots and mechanics.

\"As a unit we're kind of stressed, but everyone's accepting this as a challenge and all the men and women of the unit are acting as professionally as you could ever hope for,\" said Col. Gary Taylor, operations group commander for the Fresno-based 144th Fighter Wing of the California Air National Guard.

The unit has had to borrow F-16s from bases in Indiana and Arizona and trim back training for certain overseas operations.

A relatively small number of F-15s — the model known as the F-15E Strike Eagle — were not found to have the structural problem, and are unaffected by the grounding.

For three weeks in November, Canadian CF-18s filled in for the F-15s over Alaska. Several times, the Canadian fighters scrambled to \"do an identification\" of Russian bombers flying exercises outside U.S. airspace near Alaska, said Maj. Mike Lagace, a Canadian military spokesman for NORAD.

\"We flew up, met with the long-range patrol, basically let them know, `Hi, folks, we're here too,'\" Lagace said. Russian warplanes have been flying exercises near Alaska and Canada with increasing frequency in recent months.

Now, a brand-new squadron of F-22s based in Alaska is standing in for the state's grounded F-15s, said Tech. Sgt. Mikal R. Canfield, a spokesman at Elmendorf Air Force Base.

As for the F-15 pilots in Portland who have been largely idled by the no-fly order, they have told the visiting California airmen they are eager to get back in the cockpit.

\"They're thankful for our help,\" said Col. Ryan A. Orian, the 144th Fighter Wing's vice commander. \"But they'd love for us to leave.\"

Think the increased hours will cause trouble on the older lawndarts, with the higher tempo?

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Evil is evil, no matter how small.

I had a chance to tour the F-15 manufactoring at McDonald Douglas at Lambert in the summer of 82, they were building Saudi F-15's at the time, pretty cool process, putting out 1 every 4 days at that time.
Every Saudi F-15 had the Saudi national symbol stamped on the main part and painted on the Vertical Stabs.
Those Folks were \"Hard Core\" that we could tell, they were all \"Business\"

Their probably having trouble now because they were building the \"Stink Bugs\"(F/A-18) next to the Snoopy's. We even got to see the Proto Type F-15E with the Fast Back ext tanks installed.(Do they use them or are they part of the Jet now?)

We walked into where they were doing the \"F-4G\" mod's putting all those \"Black Boxes\" in and the other Gizmo's in.

My flight chief back then Msgt Kyle's brother-in-law was some sort of
\"Big Shot There\" so we got the \"Grand tour\" spent about 4 hours looking around .

So after seeing them being built, its hard to think one of those TECHs would let something go.

Goose

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\"Live Free Or Die\"

Actually it is a manufacturing defect. There is a point where the longeron is supposed to increase in thickness. At this particular flight station the manufacturer undercut the longeron where the thickness was supposed to increase. The width of the cutting tool was not taken into consideration when the milling machine was programmed. So there is a point where the longeron is undercut and very thin. Also there are 9 cracked jets, not eight.

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YGBSM !

Nonsense.
But as to the \"FASTpacks\" yeah they are still there and only 4 bolts hold each one on!!

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The only time you have too much fuel is when you're on fire.

sure no body made a few bucks by using less material. you know being from louisiana where the army corps cuts corners maybe a little jaded.

This is not the First time this has taken place. The other defect was in the wingbox early on. I watched in Horror as my Boss ended his career in a smoking hole

Somehow this was forgotten about when the A's became C's.

Always bad news when their is non-uniformity in the blocks and Budgets dont cover the whole fleet.

Im sure if crew-Chiefs Compare ( if they get real intimate with TCTo's) will see it in other areas of the structure,

This also Happaned with a E model at Lakenheath a couple Years Back.

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\"A good plan violently executed now is better than a perfect plan executed next week. \"

George S. Patton

http://www.af.mil/news/story.asp?id=123081524

finally some of these are cleared. I hope the 104th is one of the groups!

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If it Flys, shoot it

LOL, the fuel tank in my Porsche is held in place by more bolts than that...