Southwest Airlines problems keep growing

Now, the discount airliner has grounded 79 planes in the aftermath of a forced landing in Yuma, Ariz. yesterday.

It's not the first time a Southwest plane has developed an in-flight hole in its fuselage.

Whether the 737-300s, compared to later models of the 737, have structural problems that appear after so many flight miles or what, I don't know. But, given that Southwest has had a bit of run-ins with the FAA in the past couple of years, it had better do a thorough inspection job.

Now, it appears cracks have been found in three more planes. The fact that they're all on rivet lines would be a bit disconcerting, I think.

Update, April 5: That said, it appears this problem is Boeing's and not Southwest's. The plane maker overestimated the number of flight cycles the 737-300s could withstand before needing regular inspections.

And, that leads to this angle, the WSJ says:

For Boeing, which has built its reputation on engineering prowess and a mastery of metal airframes, the miscalculations raise questions about its new models constructed with composite materials. Half of the company's coming 787 Dreamliner, for instance, is constructed of carbon-fiber composite material, with which Boeing has far less long-term experience than it does with metal.

The story goes on to note Boeing has had one misjudgment already on the Dreamliner, specifically on its joints.