In September 2019, the FAA received reports of cracking discovered in the left and right hand side outboard chords of the station (STA) 663.75 frame fittings and failsafe straps adjacent to the stringer S-18A straps on multiple Boeing Model 737-800 airplanes during a passenger-to-freighter conversion.
PICKLE FORK CRACK
Photograph of a pickle fork crack (photo internet source unknown) Photograph of a pickle fork in situ (photo Yonhap News) Current theories include the addition of winglets which have changed the wing loading since the original design of the NG the cumulative effect of heavy landings or a manufacturing fault. The FAA said it was working with international safety regulators to understand what caused the cracks to form. When aircraft parts fail, investigators examine whether there could have been a problem with design, materials, or the manufacturing process. It is not yet clear why the pickle forks developed cracks. By, 50 aircraft had been found with cracks.īoeing is setting up a repair station in Victorville, California, and expects fixes to take two to three weeks per aircraft. It should be noted that inspections have mainly been focused on the oldest aircraft, so the percentage of aircraft with cracks found should reduce as newer aircraft are inspected. "Īircraft with more than 30,000 cycles must be inspected within seven days, while aircraft between 22,600 and 29,999 cycles must be inspected within 1,000 cycles.īy, 38 out of 810 aircraft inspected (about 5%) had been found to have cracks. The FAA is issuing this AD to address the unsafe condition on these products. This AD was prompted by a determination that the inspection area needs to be expanded. This AD also requires repetitive inspections for cracking of the left- and right-hand side outboard chords of frame fittings and failsafe straps at a certain station, but expands the inspection to the area around eight fasteners, and also requires repair if any cracking is found. AD required repetitive inspections for cracking of the left- and right-hand side outboard chords of frame fittings and failsafe straps at a certain station around two fasteners, and repair if any cracking is found.
PICKLE FORK SERIES
"AD - The FAA is superseding Airworthiness Directive (AD), which applied to all The Boeing Company Model 737-600, -700, -700C, -800, -900, and -900ER series airplanes.
![pickle fork pickle fork](https://cdn.shoptiques.com/shoptiques-shop/products/1f4da4d9-303d-4a4c-b45a-44533cf348f2_l.jpg)
As a result the FAA issued AD which expanded the inspection to the area around eight fasteners, up from two in the previous AD. On, Boeing said that after completing a round of inspections for cracking on some 737 NGs with a large number of take-offs and landings, one airplane was found to have a small crack in an adjacent location.
![pickle fork pickle fork](https://www.theantiquekitchen.co.uk/upload/images/shopprod/16162/pair-of-antique-pickle-forks_16162_main_size3.jpg)
The design life for the part is 90,000 cycles, the same as the design service life of the airframe. There are 4 pickleforks on each aircraft, 2 on the forward wing spar on the left and right side of the aircraft and two on the rear spar on the left and right side of the aircraft. The structure affected is known as a “pickle fork” because of its visual similartity with the item of cutlery, it helps attach the wing to the fuselage and manages forces. The FAA said that cracks were first discovered on aircraft being overhauled in China during conversion from passenger to cargo aircraft. In late September 2019 Boeing alerted the FAA to an issue with 737NG aircraft with more than 30,000 cycles.