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Rammjaeger
01-07-2008, 08:00 AM
I wonder how old that aircraft was:

"Last month, an F-15 disintegrated in mid-air over Missouri (the pilot parachuted to safety), and subsequent checks of the fleet's structural integrity revealed that eight of the planes have cracks in a pair of key beams just behind the cockpit. (The problem is limited to the 442 F-15A to F15D air-to-air models; the 224 stronger-framed F-15E fleet, which also can drop bombs, is a decade newer than the air superiority version and isn't affected).

Air Force officials say the strains of high-speed maneuvers have weakened the F-15s. In fact, the November 2 disintegration happened while the plane was in the middle of a 500-mph mock dogfight that put it under forces eight times that of gravity. The Pentagon is often criticized for fighting the last war, but in this case, the Air Force is fighting World War II. Winning an aerial dogfight ranks right up there with mounting a cavalry charge as required skill for today's military. Billions of dollars have been spent over the past generation buying long-range missiles such as the Phoenix and AMRAAM expressly designed to allow U.S. fighters to blast enemy airplanes from the skies long before the bad guys even see the American plane. If the U.S. military would acknowledge this, and curb its dogfighting drills, F-15s and other warplanes wouldn't wear out so fast."

http://www.time.com/time/nation/article/0,8599,1698064,00.html

Rammjaeger
01-07-2008, 08:00 AM
I wonder how old that aircraft was:

"Last month, an F-15 disintegrated in mid-air over Missouri (the pilot parachuted to safety), and subsequent checks of the fleet's structural integrity revealed that eight of the planes have cracks in a pair of key beams just behind the cockpit. (The problem is limited to the 442 F-15A to F15D air-to-air models; the 224 stronger-framed F-15E fleet, which also can drop bombs, is a decade newer than the air superiority version and isn't affected).

Air Force officials say the strains of high-speed maneuvers have weakened the F-15s. In fact, the November 2 disintegration happened while the plane was in the middle of a 500-mph mock dogfight that put it under forces eight times that of gravity. The Pentagon is often criticized for fighting the last war, but in this case, the Air Force is fighting World War II. Winning an aerial dogfight ranks right up there with mounting a cavalry charge as required skill for today's military. Billions of dollars have been spent over the past generation buying long-range missiles such as the Phoenix and AMRAAM expressly designed to allow U.S. fighters to blast enemy airplanes from the skies long before the bad guys even see the American plane. If the U.S. military would acknowledge this, and curb its dogfighting drills, F-15s and other warplanes wouldn't wear out so fast."

http://www.time.com/time/nation/article/0,8599,1698064,00.html

Bremspropeller
01-07-2008, 08:07 AM
Doesn't matter how old it is.
It's a question of mx.


We have 7000+ hour Rhinos over here which are well over 30 years.
And they are still kicking azz http://forums.ubi.com/images/smilies/winky.gif ...well, sometimes http://forums.ubi.com/images/smilies/shady.gif

HotelBushranger
01-07-2008, 08:25 AM
So they're complaining that a very old plane is weak? Huh...who woulda thought a military fighter put through its paces would get tired?

And this last paragraph:

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">The Air Force's next challenge will be to convince those who hold the purse strings to build more of a plane designed for an enemy, and a kind of war, that no longer exists </div></BLOCKQUOTE>

It also pays to be prepared; better to have a lot of expensive, superior fighters in readiness for an unforeseeable war, than to be caught with your pants around your ankles with 30 year old aircraft and more cash. Remember its the lives of the pilots they're gambling by assuming they won't come up against a reasonable opponent into the near future.

MEGILE
01-07-2008, 08:43 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Rammjaeger:
If the U.S. military would acknowledge this, and curb its dogfighting drills, F-15s and other warplanes wouldn't wear out so fast."

</div></BLOCKQUOTE>

The day you quit practising dogfighting, is the day your missiles fail and your tail gets waxed.
The USAF has learned not to go down that route, yet.

Sergio_101
01-07-2008, 08:48 AM
It' all part of the math of warfare.
That BRUTAL arithmatic that tells you things
like how long you will have those wonderful
missles before you run out.

I was in the USAF, I remember stories about
running out of
old fasion iron bombs in vietnam.
Running out of Sidewinders for fighters.

Think the small scale, your on a mission and you fired all your missles.......
If a pilot can not dogfight then he's a sitting duck.
after the missles are fired.

And, the wing spar cracks that caused the F-15 crash
are really not a big deal.
They will be repaired, and additional inspections
will be added or more frequent PDM will be
performed.

Really NOT a big deal.

Sergio

Bremspropeller
01-07-2008, 09:02 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">They will be repaired, and additional inspections
will be added or more frequent PDM will be
performed.

Really NOT a big deal. </div></BLOCKQUOTE>

+1

huggy87
01-07-2008, 10:04 AM
We've had similar problems in the FA-18 fleet. The center barrel fatigued at greater rates than expected. Slamming into carriers we'll do that to a plane. We have also discovered other problems that were never even anticipated or planned for.

Bremspropeller
01-07-2008, 10:14 AM
Was the Hornet always (down)rated to 7.5gs, or was that a result of the fatigue-cracks that develloped in the late 80s?
I figure they later added those vortex-generators on the LERX to prevent that.

mortoma
01-07-2008, 10:25 AM
They thought that dogfighting was over by the late fifties. Then look what happened in Viet Nam, in the first part of the war we got smoked by agile Soviet fighters. Then had to open up dogfighting schools like red flag to teach dogfighting again.
They also had to mount close range weapons, like cannons on Phantoms and some others aircraft.

Bremspropeller
01-07-2008, 10:51 AM
Red Flag is not a "dogfight school", as you put it.

It's an exercise, simulating an entire "hot" conflict.

The dogfight-schools you mean are the USN FWS, known as "Top Gun" and the USAF FWS.

jarink
01-07-2008, 11:32 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Rammjaeger:
...the Air Force is fighting World War II. Winning an aerial dogfight ranks right up there with mounting a cavalry charge as required skill for today's military. </div></BLOCKQUOTE>

Geez, was this written in 1957 or 2007? http://forums.ubi.com/images/smilies/blink.gif

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Billions of dollars have been spent over the past generation buying long-range missiles such as the Phoenix and AMRAAM expressly designed to allow U.S. fighters to blast enemy airplanes from the skies long before the bad guys even see the American plane. If the U.S. military would acknowledge this, and curb its dogfighting drills, F-15s and other warplanes wouldn't wear out so fast." </div></BLOCKQUOTE>

This is probably one of the same people that required visual identification of aircraft targets in Vietnam. Stupid McNamara beancounters. Don't they realise that the F-15 is probably the longest-lived frontline fighter ever in the USAF inventory??

VW-IceFire
01-07-2008, 03:26 PM
Interesting update in the information but that has to be one of the most historically and technically ignorant articles I've read in some time and I read allot!

Long range missiles should not be at all confused with the ability to simply shoot the other planes out of the sky without further mess. Thats assuming 100 percentage kill and no ECM and no maneuvering and so on and so forth. There's a reason why the latest round of weapons has been focused on super maneuverable short range missiles and accompanying technology and not ultra long range ones. I guess they never heard of Vietnam or the lessons learned there.

JarheadEd
01-07-2008, 03:44 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Bremspropeller:
Was the Hornet always (down)rated to 7.5gs, or was that a result of the fatigue-cracks that develloped in the late 80s?
I figure they later added those vortex-generators on the LERX to prevent that. </div></BLOCKQUOTE>

The Hornet was always rated at 7.5G but that can be over-ridden (sp) in the heat of the moment, and the lex fences came about due to cracks at the base of the vert stabs.

Blottogg
01-07-2008, 07:18 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Bremspropeller:
Doesn't matter how old it is.
It's a question of mx.


We have 7000+ hour Rhinos over here which are well over 30 years.
And they are still kicking azz http://forums.ubi.com/images/smilies/winky.gif ...well, sometimes http://forums.ubi.com/images/smilies/shady.gif </div></BLOCKQUOTE>

Hey, Brems. Are they still smokin', or did they finally mod the engines to be smokeless? I still remember doing a visual sort west of Low Fly 3 (NW of Munich) when I got handed the tactical lead at 15 miles. I was the only one with a radar picture... and we didn't actually see them 'till we got closer, but we definitely saw them before they saw us.

I agree with Sergio and Huggy87, this is pretty commonplace as airframes age. T-38's gained a longeron doubler on both sides of the fuselage to correct a similar problem (and are on their third or fourth set of wings...) Vipers have had wing carry-through cracks, especially the Block 30's (which have the same structure as the lighter A models... the later Block 40's and 50's got beefed up, and heavier.)

Even though they do fatigue testing, the loads and repititions are really just best guesses as to how the aircraft will be used. Real-world operations invariably differ from that testing, and changes need to be made. We're getting to the point on some of these older airframes where there is an element of test piloting in continuing to fly them. I'm glad to hear he got out alright, and hopefully the fleet will be back up soon. From what I've read, their grounding is starting to put a strain on the rest of the F-16 equipped interceptor units. It does highlight the benefit of a diverse fleet of aircraft and engines though, doesn't it?

As far as not flying BFM in order to preserve airframe life, that is of course stupid. By the same logic, we could provide our Air Force with unlimited airframe life if we'd just never fly the aircraft (an argument the UCAV crowd is actually making, with a little more practicality.) BFM skills are most definitely not like riding a bicycle... the skills deteriorate quickly without practice. It's not the fight of choice, especially in an age of HMS's and IIR missiles. But merges still happen, and ignoring that possibility won't make it any less likely, it'll just make the ignorer that much less prepared to deal with it.

Rammjaeger
01-07-2008, 10:14 PM
The idea that dogfighting skills have become irrelevant had been around for decades indeed but the combat experience of the USAAF since the Cold War - the simple fact that everyone refuses to fight against it on equal terms - seems to confirm that view to a certain extent. This idea was certainly not based on solid ground during the conventional wars in 1945-1991.

Under what possible circumstances would an F-15 need to carry out violent manoeuvers? I guess that's a relevant question. And the fact that the USAF already wants to phase out the F-15 because of such accidents and already doubled its request for F-22s - well, one is left to wonder what is their motivation behind all that.

huggy87
01-08-2008, 08:54 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Bremspropeller:
Was the Hornet always (down)rated to 7.5gs, or was that a result of the fatigue-cracks that develloped in the late 80s?
I figure they later added those vortex-generators on the LERX to prevent that. </div></BLOCKQUOTE>

It was always rated to 7.5gs. However there is a "paddle switch" near the stick that you could use in extremis to override the g limiter and pull more. Of course, you'll probably bend the jet.

jarink
01-08-2008, 11:21 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Rammjaeger:
Under what possible circumstances would an F-15 need to carry out violent manoeuvers? I guess that's a relevant question. And the fact that the USAF already wants to phase out the F-15 because of such accidents and already doubled its request for F-22s - well, one is left to wonder what is their motivation behind all that. </div></BLOCKQUOTE>

I would suppose it has to do with maintenance costs more than anything else. That's why the USN retired the F-14, not because it lacked any capabilities or because the F/A-18E/F was better (in many ways it isn't).

Bremspropeller
01-08-2008, 11:36 AM
Thanks for making things clear, Jarhead and Huggy http://forums.ubi.com/images/smilies/25.gif

Blotto, they're still smokin http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif
It's a combination of the original smoker-engines, de-rated power and engine-preserving fuel - I had a conversation with a retired "Phantom Phixer" about that http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

A Richthofen-Rhino:
http://www.airliners.net/open.file/1306594/L/

T_O_A_D
01-08-2008, 04:11 PM
My real question is, How is it I live in Missouri and had to be told about this, via an out of stater from a dang forum last week.

It was never even mentioned on the TV or news papers here localy.

berg417448
01-08-2008, 04:34 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by T_O_A_D:
My real question is, How is it I live in Missouri and had to be told about this, via an out of stater from a dang forum last week.

It was never even mentioned on the TV or news papers here localy. </div></BLOCKQUOTE>

It was all over the national news when it happened. I know CNN did a story on it.

Viper2005_
01-08-2008, 05:15 PM
Missiles may be very good at killing things, but they aren't very good at telling the difference between friend and foe.

Modern missiles might be able to tell the difference between an F-15 and a MiG-21, but these days some of the good guys might be flying MiG-21s too.

Therefore, in order to avoid politically undesirable friendly fire accidents, it may be necessary to get rather closer than is suggested by the available missile performance.

As such, it is probably a good idea to keep those dogfighting skills alive.

Anyway, irrespective of the precise relevance of the dogfight to modern aerial combat, I suspect that many of the basic skills are directly transferable (eg the maintenance of good SA, knowledge of the real edges of the flight envelope etc.).

As for this being no big deal, I wouldn't go that far; a man was nearly killed, and cracks were found in several aircraft in the fleet. I suspect however that the USAF may have made more fuss than was strictly necessary in the hope that doing so will strengthen their case for buying more F-22s...

Bremspropeller
01-08-2008, 06:38 PM
Is the grounding still active?

berg417448
01-08-2008, 09:28 PM
This article says that 260 of them will be returning to service starting January 9, but that 180 will remain grounded.

"Many of them may never fly again," a senior Air Force officer said. The officer, like others interviewed for this article, spoke on condition of anonymity because results of the investigation are not due to be made public until today."

http://www.latimes.com/news/nationworld/nation/la-na-ai...?coll=la-home-center (http://www.latimes.com/news/nationworld/nation/la-na-airforce9jan09,0,1358206.story?coll=la-home-center)

Sergio_101
01-09-2008, 02:17 AM
Many will not fly again.....
Those that are near retirement will not be
fixed. Or in some cases not inspected.
The F-15 has been flying since 1973.
I seem to remember Langly field getting
the first active duty F-15B(?) about mid 1976.
May have been F-15A.

Anyhow, there are some very old F-15s still flying.

What happens is the aircraft will be flown to Davis Monthan AB on a
temp sign off. We called it a Flying red "X".
If a old bird is deemed not airworthy at all it will
be stripped and scrapped in place.

Bottom line is you don't spend big $$$ on a plane that is sceduled
for decomissioning in the very near future.

Sergio

Enforcer572005
01-10-2008, 09:40 PM
I see this "dogfighting is dead" thread all the time, as this 'flat earth' type philosophy has been repeatedly promoted since the thirties (Planes like the Hurricane were considered too fast to survive the g forces). Countless combats since the fifties have shown that ACM must be taught and practiced, or you will be defeated. SecDef Robert Macnamara was a total village idiot that knew nothing of military science or history, and he said the same thing, nearly word for word. That genius thought the F-111 would be the only plane all the military services needed, and that it could operate off carriers.

And you better have guns on fighters to.

Airplanes wear out after about three decades or so of use, especially military use. Restored WW2 planes have extensive work done on them to keep them flying, and this wouldn't be practical from an economical standpoint for combat planes.

The F-22 went into squadron service a decade late due to a certain admin delaying it hoping it would go away. We need new planes, and we need them pretty quickly. Whatever they may be. Manned planes, with guns and missles. You have to replace stuff that wears out....nature of any manufactured product on this planet. Rebuilding gets economically unworkable after a time. How well do you think your car would hold up after 20 to 30 yrs?

VW-IceFire
01-10-2008, 10:20 PM
So very true...the articles I've been reading seem to suggest that most of the major Air Forces have been waiting to get their birds replaced for quite a while. Development in the 1940s, 1950s, and 1960s was so rapid that new designs were coming up all the time. Things are considerably slower now...capabilities still expand but the plane itself is mostly the same. They wear out...its going to start happening to more than just the F-15s. Tip of the ice burg I think.

Sergio_101
01-11-2008, 02:36 AM
There are some VERY old warplanes in the uS inventory.

For instance, the last B-52 was delivered in mid 1964!
That makes the youngest B-52H 44 years old!

There are older C-130s on active duty.
I believe there are a couple of 1958 C-130B's
still flying with the ANG/Reserves.

Warplanes actually can be kept fit indefinately.
The problem here is more about the fact that after 35 years
the world is finnaly catching up with the performance of
early F-15s.

As I said eariler, this is not a real problem, only a tempoary
glitch.

What is completely different for the USAF is that a fighter plane has been on the front line
as an effective air superiority fighter for 35 years.
We have thrashed those F-15s hard, things are starting to fail
that we never suspected might be a problem.

The F-22 is a massive improvment in all aspects of performance.
The F-15 will soldier on for another few decades, (longer in foreign service).

We need the F-22, and need it badly.

Pilotless fighter planes are in the very near future and the issue is
that the F-22 will have a short service life as a result.

Sergio

leitmotiv
01-11-2008, 11:51 AM
http://www.defenseindustrydaily.com/aging-aircraft-usaf...leet-grounded-04149/ (http://www.defenseindustrydaily.com/aging-aircraft-usaf-f-15-fleet-grounded-04149/)

DrHerb
01-11-2008, 05:48 PM
theyll probably have to crack test using FPI (Fluid Penetrant Inspection) or MPI (Magnetic Penetrant Inspection)on critical frame components at a more frequent basis.