Since the issuance of emergency AD 2007-18-51, the FAA received additional reports of parts coming off the main slat track downstop assemblies on B737NG aircraft. In these cases, the parts were found in the bottom of the slat track housing. Additionally, in one case, this slat can was damaged.
Based on this new information, the FAA finds that the 24-day compliance time specified in AD 2007-18-51 for accomplishing the detailed inspection of each main slat track downstop assembly to verify proper installation of the slat track hardware is not adequate to address the unsafe condition. The appropriate compliance time for this inspection is 10 days after receipt of this new AD. In addition, an inspection using borescope techniques in lieu of a detailed inspection is acceptable.
By performing the initial detailed or borescope inspection within the reduced compliance time of 10 days, the compliance time for torquing the nut and bolt remains at 24 days after receipt of AD 2007-18-51. (FAA)