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.
National Transportation Safety Board member Robert Sumwalt said Sunday that the rip in the jet that made an emergency landing in Yuma, Ariz., on Friday was a foot wide.
It started along a lap joint where two sections of the Boeing 737-300's skin are riveted together.
Southwest mechanics will cutt 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.
The jet had leveled off at 36,000 feet after taking off from Phoenix when the skin ruptured. The pilots rapidly descended. One flight attendant was hurt.