The CFM engines subject to the emergency directives number 681 worldwide and 352 in the US.
The CFM56 arguably the most popular jet engines in the world with more than 30,000 units produced since 1980 and is used on both civilian and military aircraft.
Airlines is given a nine months to check the engines by the European agency; while U.S regulators still considering what need to go. The directive stipulates that these inspections must be completed within the next 20 days.
The FAA said airlines have 20 days to carry out ultrasonic inspections of fan blades on CFM56-7B engines that have made more than 30,000 flights.
The National Transportation Safety Board is onsite inspecting a Southwest airline plane after engine failure caused the plane to make an emergency landing at Philadelphia International Airport.
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Mr Sumwalt also said a casing on the engine was meant to contain any parts that come loose but, due to the speed at impact, the metal was able to penetrate the shell.
A Southwest Airlines Boeing 737 made an emergency landing in Philadelphia on Tuesday after the left engine exploded in mid-air. An investigation into that incident is still underway, but the NTSB said it had also found evidence of metal fatigue.
FAA's directive describes its requirement as "a one-time ultrasonic inspection (USI) of all 24 fan blade dovetail concave and convex sides to detect cracking" within 20 days. She was pulled back in by other passengers, but later died of her injuries.
More than 150 have already been inspected. When asked why the airline resisted the proposal previous year, spokeswoman Brandy King said Southwest needed more time to find individual suspect blades within certain engines.
US and European airline regulators on Friday ordered emergency inspections within 20 days of almost 700 aircraft engines similar to the one involved in a fatal Southwest Airlines (LUV.N) engine blowout earlier this week, citing risks of a similar mishap.
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The NTSB will look into how an interior crack on a fan blade led to the engine failure.
"Injured passengers, okay, and is your airplane physically on fire?" asks a male voice in the tower, according to a recording released by officials.
CFM International had issued a similar recommendation in 2016 after the failure of a CFM56-7B engine on another Southwest aircraft.
"The public should be anxious (because) a manufacturer sent out a warning, and Southwest and others didn't do it", said Mary Schiavo, a former inspector general of the Transportation Department, FAA's parent agency.
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