Action
Final rule.
Summary
We are adopting a new airworthiness directive (AD) for all The Boeing Company Model 737-100, -200, -200C, -300, -400, and -500 series airplanes. This AD was prompted by reports indicating additional cracking in the inspar upper skin at wing buttock line (WBL) 157 and in the skin at two holes common to the rear spar in the same area, and rear spar web cracks were also noted on both wings. Subsequent inspections revealed that the right rear spar upper chord was almost completely severed and the left rear spar upper chord was completely severed. Additional reports identified cracking in the main landing gear (MLG) beam forward support fitting. This AD requires the installation of standard-size fasteners for a certain configuration and inspections for any crack in certain locations of the rear spar. We are issuing this AD to address the unsafe condition on these products.