Summary
The FAA proposes to adopt a new airworthiness directive (AD) for certain Boeing Model 737-300 and -400 series airplanes. This proposed AD would require testing and inspecting a certain web panel of the main wheel well pressure deck to determine the material type and thickness; and related investigative and corrective actions if necessary. This proposed AD results from several reports indicating that cracks ranging from 0.8 to 8.0 inches long were found on a certain web panel of the main wheel well pressure deck. We are proposing this AD to prevent fatigue cracking in the web panel of the main wheel well pressure deck, which could result in venting and consequent rapid decompression of the airplane.