Airworthiness Directives; The Boeing Company Model 737-600, -700, -700C, -800, and -900 Series Airplanes

Résumé

We propose to adopt a new airworthiness directive (AD) for certain Model 737-600, -700, -700C, -800, and -900 series airplanes. This proposed AD would require inspecting for part numbers of the operational program software of the flight control computers, and doing corrective actions if necessary. This proposed AD results from reports of erroneous undetected output from a single radio altimeter channel, which resulted in premature autothrottle retard during approach. We are proposing this AD to detect and correct erroneous output from a radio altimeter channel, which could result in premature autothrottle landing flare retard and the loss of automatic speed control, and consequent loss of control of the airplane.