Older Boeing 737 Jets Are at Risk for Cracks

The recent events of the Southwest -300 version brought me back to this image I had taken a while back of another -300. Take a look at the repair/patches/rivets that have been applied on it. Is this really safe (or FAA approved) to do ?

http://www.jetphotos.net/viewphoto.php?id=6240832

regards,
Saurabh

One wonders if the fuselage thikness of the Boeing jets are thinner than what they should be, too many accidents and incidents. So far Airbus has not had anything like this but the authorities should be monitoring them too.