AP reports:
Federal investigators say the entire length of a 5-foot-long tear in the skin of a Southwest Airlines Boeing 737 shows evidence of pre-existing fatigue cracking.
It started along a lap joint where two sections of the Boeing 737-300's skin are riveted together.
Southwest mechanics will cut the entire ripped section out of the plane on Sunday. Sumwalt says he expects a 9-foot by 3-foot section will be sent to Washington D.C., for analysis.