"We're not required to inspect them right now, but we felt it was the prudent thing to do, and to help the industry determine the proper interval," spokesman Paul McElroy said.
There are about 6,000 737s in operation worldwide, and an emergency FAA order on Tuesday only covers 579 that have the type of "lap joint" that failed during last week's flight. Lap joints are used in many places on an aircraft fuselage and get their name because it is the spot where the aluminum skin of the aircraft overlaps and is secured with rivets. The FAA order focuses on a Boeing joint design on planes made between 1993 and 2000.
Experts say that all of the planes around the world will be covered by the FAA order because of international agreements between civil aviation regulators globally. Many of the inspection orders handed down by foreign governments mirrored the one issued by the FAA.
Henry Harteveldt, aviation analysis at Forrester Research, Inc. in San Francisco, said that some airlines may not always maintain their airplanes to the highest levels of safety. "But I would make very clear that the top tier U.S. and foreign flag airlines do this. Airlines like British Airways, Qantas and so on, those airlines maintain their airplanes to the highest standards and the best record-keeping."
The FAA said all of the planes have to undergo inspections when they reach the threshold of 30,000 takeoffs and landings. The 175 of those planes that have already reached the threshold are getting immediate inspections.
For example, the planes owned by the crown prince of Thailand and Chinese Air Force have only flown about 5,000 cycles each, meaning their planes have a long ways to go before an inspection. One of the Swedish planes has more than 40,000, requiring an immediate examination.