Summary
We propose to adopt a new airworthiness directive (AD) for all The Boeing Company Model 727 airplanes. This proposed AD was prompted by reports of cracks on the elevator rear spar stiffener assembly. This proposed AD would require repetitive detailed inspections for cracking of the elevator rear spar stiffener assembly, and corrective actions if necessary. We are proposing this AD to detect and correct cracking of the elevator rear spar stiffener assembly, which could adversely affect elevator structural stiffness, that could lead to elevator vibration and possible interference with the tab control rod and which could result in flutter and consequent loss of control of the airplane.