Page 2 - Lap Joints News Today : Breaking News, Live Updates & Top Stories | Vimarsana

Spread cracking across this entire fracture surface. >> reporter: damages along one of the lap joints not detected in regular maintenance checks. >> what the issue is is that along this particular lap joint, it was not known in the industry that this was an area on airplanes of this number of cycles that those lap joints should be inspected. >> reporter: boeing, the maker of the 737 300, is drafting a service bulletin to require special inspections of the lap joints in all of the 737s with comparable landing and takeoff cycles. southwest airlines has returned 19 of the grounded 737 300s to ser...

Now these are very small cracks, none of the same scale as the plane that was forced to make the emergency landing in yuma, arizona. but they did find these three cracks and they plan to do whatever they have to do fix them. the bigger context are, or the bigger question as it relates to this 737, is why did they not find this crack a year ago when they did a major overhaul, a 14-year overhaul. the answer seems to be that they -- the cracking was in a place they had never seen cracking before, in a plane with so few, for 14 years, cycles, a cycle is every time you take off or land. they found ...

Cycles that those lap joints should be inspected. >> nbc news got faa records which show that during a heavy maintenance overhaul in march 2010, inspectors found multiple cracks along the fuselage of this particular 737 300. a frame crack, 867 inches from the nose, another 380 inches from the nose, 500 inches from the nose and many more. but the ntsb says it is not uncommon for a 14-year-old plane. >> some wear and tear on an airplane is perfectly normal. an airplane is constantly pressurized, depressurized and that creates some wear and tear over time. >> last night, flight 1588 from oakland ...

In service. >> we found evidence of additional cracks on that airplane. >> reporter: investigators in yuma, arizona removed a large section of that 737 that made an emergency landing friday night. that piece will go through tests at the ntsb lab in washington but already investigators say there are clear signs of pre-existing fracture lines on the aircraft's skin along a lap joint. >> what the issue is that along this particular lap joint it was not known in the industry that this was an area on airplanes of this number of cycles that those lap joints should be inspected. >> reporter: new pass...

Them middle-aged, but every time they take off and they go down and land, they go through compression and decompression, which puts stress on the aircraft, and that kind of use is factored in when they try to calculate the maintenance schedules for the aircraft. >> i guess that's sort of like a balloon, when the plane goes up in the air, the balloon inflates and when it comes down, it deflates and that makes it hard for the structure of the plane. two years ago, southwest was cited. it was actually fined millions of dollars for similar problems. you'd think that those problems would have gone ...