Airworthiness Directives; Boeing Model 727 Airplanes

We are adopting a new airworthiness directive (AD) for all Boeing Model 727 airplanes. This AD requires repetitive inspections for cracking or corrosion of the threaded end of the lower segment of the main landing gear (MLG) side strut, and corrective actions if necessary. This AD also requires prior or concurrent inspection for cracking or corrosion of the threads and thread relief area of the lower segment, corrective action if necessary, and re-assembly using corrosion inhibiting compound. This AD results from reports of the threads cracking on the MLG side strut lower segment. We are issuing this AD to prevent a fractured side strut, which could result in collapse of the MLG.