Boeing has been ordered to begin carrying out inspections on all 737 NG models, namely the 737-600, -700, -800 and -900. The currently troubled 737 MAX is excluded from the FAA order. The problem concerning the cracking came to light when a number of 737-800s were being converted from passenger aircraft to cargo aircraft. The FAA has demanded the immediate inspection (within the next seven days) of 165 registered 737-800s, all of which have clocked a great many flight hours.
According to the FAA, if the problem is not effectively addressed, the cracking could: “adversely affect the structural integrity of the airplane and result in loss of control of the airplane.” The FAA statement relating to this order indicated that Boeing “discovered the cracks while conducting modifications on a heavily used aircraft. Subsequent inspections uncovered similar cracks in a small number of additional planes.” The part is called a pickle fork. While the order will ultimately affect over 2,000 aircraft, the urgency of inspections will depend on the number of flight hours performed by each individual aircraft and further inspections will be required based on thresholds hit.
Southwest Airlines has a fleet of approximately 700 737 NGs, none of which will require immediate inspection, while United Airlines confirmed it has no 737 NGs requiring immediate inspection but 80 will require inspecting in the near future. American Airlines has 304 737 NGs but has confirmed that none will require immediate inspection, while Delta Air Lines has a fleet of 200 737 NGs, of which 50 are affected by the FAA’s inspection order, but none require immediate inspection. Inspections of the wing supports is estimated to take approximately one hour.