Summary
We propose to adopt a new airworthiness directive (AD) for certain Airbus Model A300 B4-600 and A300 B4-600R, Model A300, and Model A310 series airplanes. This proposed AD was prompted by reports of fatigue cracking in the crossbeams at the junction of the actuator beam of the lower deck cargo door. This proposed AD would require repetitive inspections of the crossbeams of certain fuselage frames, and repair if necessary. We are proposing this AD to detect and correct cracking of the crossbeams at the junction of the actuator beam of the lower deck cargo door, which could result in failure to withstand ultimate load conditions, and consequent reduced structural integrity of the airplane.