Airline engine explosion during flight
Last month Southwest Airlines 737 flight 1380 was forced to make an emergency landing in Philadelphia as a result of one of its engines blowing up in mid-flight flying from New York to Dallas. One passenger was killed as the resulting shrapnel from the engine explosion shattered a window. It was determined the next day that the explosion was caused by metal fatigue of one of the turbine blades. This is a rare occurrence since plane engines are normally inspected for wear and fatigue and the CFM56-7B engine.
This is the second engine to blow
This is the second CFM56-7B engine that has exploded as there was an incident in 2016 also on a Southwest flight. In both cases, an engine fan blade broke off causing the engine to explode. The National Transportation Safety Board declared that both cases were due to metal fatigue.
CNN reported, “In Aviation, there should be inspection techniques and procedures in place to detect something like (metal fatigue),” said NTSB Chairman Robert Sumwalt. “We want to find out why this was not detected ahead of time.”
The CFM56-7B engine is typically found in the 737 and southwest is not the only airline that uses it. The FAA has ordered Southwest to inspect any engines that have exceeded 30,000 landing and takeoffs or 20 years of service. Other airlines are also ordered to break out their borescopes and inspect all engines of that type that have logged 20,000 cycles. They do have a more time to complete that task though. Southwest have been scrambling to meet the FAA mandate cancelling some of its flights and delaying others.
There are hundreds of Jets with old engines in the air
There are hundreds of these engines in service now needing inspection. United Airlines has 698 of the CMF56-7B engine in its fleet. Ryanair has 70 of its 440 737 jets also outfitted with the older engine. American Airlines said that since the 2016 incident that they have already been inspecting all engines of that model. Other airlines that use the engine includes the larger portion of China’s commercial fleet including Air China, China Southern, China Eastern, and Hainan. All who will also be required to complete inspections.
The engine maker CFM, which is a joint venture of GE and France’s Safran SA, in response to the incident called for airlines to inspect the engines within 12 months. Not without pushback from the industry though stating that the high costs and inconvenience of such endeavor would be too crippling to daily operations.
Are the safety standards slipping?
The engine has 24 fan blades and one longtime industry practice was to only check a few of those blades during an inspection picked at random. The FAA specifically demanded this time around that every airline complete a “one-time check of all 24 fan blade” sides to detect cracks and to replace before putting the plane back online in the air. Using specialized tools like borescopes the engine doesn’t have to be complete disassembled complete the inspection though it is still a time consuming process. Both the FAA and the NTSB has also been criticized because the probe on the 2016 incident still hasn’t been completed and that congress may investigate. Examination of agency records showed that enforcement of aircraft maintenance compliance has slipped by 70 percent in recent years according to Senator Chuck Schumer. “60 Minutes” just ran an expose on the budget airline Allegiant Air for its alleged safety and maintenance failings. That was unfortunately too little, too late for one passenger and her family of southwest flight 1380.