Summary
We propose to adopt a new airworthiness directive (AD) for all Lockheed Martin Corporation/Lockheed Martin Aeronautics Company Model 188 series airplanes. This proposed AD was prompted by an evaluation by the design approval holder (DAH) indicating the left and right lower surface panels of the wings are subject to widespread fatigue damage (WFD). This proposed AD would require repetitive inspections for cracking at these panels, and repair if necessary. The proposed AD would also require a one-time bolt-hole eddy current inspection of all open holes for cracking, repair if necessary, and modification. We are proposing this AD to prevent fatigue cracking of the left and right lower surface panels of the wings, which could result in reduced structural integrity of the airplane.