The discovery of cracks in the pickle forks of some 737NG aircraft has raised major concerns. Cracks in a structural component designed to be safe for the life of the aircraft, or 90,000 cycles, is serious. Boeing, in modifying some older 737NGs for cargo conversion, discovered cracks in aircraft with only about 33,500 flight cycles, or about 1/3rd of the expected life. There are four pickle forks that hold the wing to the fuselage, so a failure could have catastrophic results if a crack was to propagate into a component failure.
has issued an airworthiness directive to inspect Boeing 737NG aircraft with more than 22,600 cycles within a year, and for aircraft with more than 30,000 cycles within one week. Inspections can be completed by borescope without a major teardown of the airframe, and will likely be conducted overnight by most airlines. Of course, where cracks have been found, replacement will be necessary, which, given the need to tear the aircraft down to its basic structure as in a D-Check, and that substantial hangar time cannot be inexpensive.
With most narrow-body aircraft flying about 3,000-3,500 cycles annually, problems seem to be emerging on aircraft more than 11 years old. Given that there are thousands 737NGs in service, a major problem would be costly for Boeing.
The discovery of cracks in the pickle forks of some 737NG aircraft has raised major concerns. Cracks in a structural component designed to be safe for the life of the aircraft, or 90,000 cycles, is serious. Boeing, in modifying some older 737NGs for cargo conversion, discovered cracks in aircraft with only about 33,500 flight cycles, or about 1/3rd of the expected life. There are four pickle forks that hold the wing to the fuselage, so a failure could have catastrophic results if a crack was to propagate into a component failure.
The FAA has issued an airworthiness directive to inspect Boeing 737NG aircraft with more than 22,600 cycles within a year, and for aircraft with more than 30,000 cycles within one week. Inspections can be completed by borescope without a major teardown of the airframe, and will likely be conducted overnight by most airlines. Of course, where cracks have been found, replacement will be necessary, which, given the need to tear the aircraft down to its basic structure as in a D-Check, and that substantial hangar time cannot be inexpensive.
With most narrow-body aircraft flying about 3,000-3,500 cycles annually, problems seem to be emerging on aircraft more than 11 years old. Given that there are thousands of 737NGs in service, a major problem would be costly for Boeing.
We use cookies to optimize our website and our service.
Functional
Always active
The technical storage or access is strictly necessary for the legitimate purpose of enabling the use of a specific service explicitly requested by the subscriber or user, or for the sole purpose of carrying out the transmission of a communication over an electronic communications network.
Preferences
The technical storage or access is necessary for the legitimate purpose of storing preferences that are not requested by the subscriber or user.
Statistics
The technical storage or access that is used exclusively for statistical purposes.The technical storage or access that is used exclusively for anonymous statistical purposes. Without a subpoena, voluntary compliance on the part of your Internet Service Provider, or additional records from a third party, information stored or retrieved for this purpose alone cannot usually be used to identify you.
Marketing
The technical storage or access is required to create user profiles to send advertising, or to track the user on a website or across several websites for similar marketing purposes.
