I just saw a report saying that the Southwest 737-300 in this incident had nearly 40,000 takeoff and landings. These guys really get their moneys worth out of their 737's.

I just saw a report saying that the Southwest 737-300 in this incident had nearly 40,000 takeoff and landings. These guys really get their moneys worth out of their 737's.

They sure got their money's worth out of this one. Any time you get to do a successful controlled landing after sustaining that much damage, that plane has earned its keep.

An ABC report last night stated, after an initial inspection of Southwest's 737-300's, they have found an additional 3 aircraft with cracks in the fuselage. The FAA has grounded all of them.I believe it was recently, within the last 2 years. I think it was right around the time American Airlines was being sited for problems with their MD-80's.

Yeah there was that one, but there was another less publicized one I remember because my father was on the review team for it which one the scale of this most recent one.

Isn't it interesting, that nearly 60 years after the deHavilland Comet disasters, metal fatigue continues to haunt the aviation industry. One wonders what the introduction of composite materials will bring.AR

Isn't it interesting, that nearly 60 years after the deHavilland Comet disasters, metal fatigue continues to haunt the aviation industry. One wonders what the introduction of composite materials will bring.AR

Unfortunately I believe it will be much the same. The cost of maintenance will also go up because of training and new procedures for damage on composites.

Unfortunately I believe it will be much the same. The cost of maintenance will also go up because of training and new procedures for damage on composites.

AA Flight 587 went down in 2001 at JFK. The cause of the crash was determined to be excessive rudder control by the crew resulting in overstress and separation of the plane's tail. The composite parts in the tail assembly were determined to have failed, but they were subjected to forces in excess of what they were designed to handle. This was an A300.

Some interesting info from Bloomberg News on the Boeing 737 metal fatigue problem.http://www.bloomberg.com/news/2011-04-05/boeing-says-737-jet-cracking-happened-earlier-than-expected.htmlAR

One news report said that the failure on the SWA plane was in a non-exposed area which is not usually looked at in routine inspections. Given the history of the Aloha incident, I'm surprised they don't make sure to check these non-exposed areas more regularly.

Per the Boeing engineer for this fleet:"The April 1 incident was “a statistical event” and doesn’t have anything to do with Southwest’s maintenance program or with how the carrier operates its planes, Richter said."Boeing knew that the first 737s, which the company began building in Seattle in 1967, would have problems along the lap joints, and the FAA already has devised inspections and repairs for those planes, Richter said. The company changed the design for all 737-300s, -400s and -500s built after 1993, and those are the ones that weren’t expected to start cracking until they reached 60,000 cycles."By 2000, when the models known as Next-Generation 737s began to be built, the company had developed a new design that’s “significantly different and much improved,” Richter said. Engineers were able to reduce how much the metal fuselage bends when the plane is pressurized as it ascends, he said. "So the difference from Aloha is that that was a -200, and the design of the lap joint was changed for the -300.scott s..

Isn't it interesting, that nearly 60 years after the deHavilland Comet disasters, metal fatigue continues to haunt the aviation industry. One wonders what the introduction of composite materials will bring.AR

It won't be fatigue, as CFRPs have no endurance limit when exposed to cyclic loading, buth then there's delamination from lightning strike heat due to loss of Faraday Cage effect to keep the folks at the FAA/NTSB busy!Cheers.- jahman.

It won't be fatigue, as CFRPs have no endurance limit when exposed to cyclic loading, buth then there's delamination from lightning strike heat due to loss of Faraday Cage effect to keep the folks at the FAA/NTSB busy!Cheers.- jahman.

As for the faraday they wrap copper I believe through the fuselage.

Here is another good read:http://rdougwicker.com/2011/04/03/why-southwests-boeings-keep-coming-apart-above-30000-feet%E2%80%94part-i/

Aloha 243 was ruled to have suffered metal fatigue, made worse by corrosion from operating in the Hawaiian environment. The aircraft involved had over 89,000 cycles, the second most for any aircraft then operating worldwide. The NTSB report specifically mentioned multiple-site failures at the lap joints. The plane was 19 years old.