Summary
We propose to adopt a new airworthiness directive (AD) for certain Model 737-700 (IGW) series airplanes. This proposed AD would require deactivation or modification of PATS Aircraft, LLC, auxiliary fuel tanks. This proposed AD results from fuel system reviews conducted by the manufacturer. We are proposing this AD to prevent the potential of ignition sources inside fuel tanks, which, in combination with flammable fuel vapors, could result in fuel tank explosions and consequent loss of the airplane.