FAA has issued airworthiness directive 2021-19-12 MHI RJ Aviation RJ700s, 701s, 702s, 550s, 705s, 900s, and 1000s, requiring detailed inspections for corrosion on the main landing gear outer cylinder assemblies, certain dressed shock strut assemblies, and the outer cylinder at the gland nut threads, thread relief groove and chamfer; a detailed inspection for the presence of corrosion-inhibiting compound on the forward and aft trunnion pins and grease adapter assemblies; applicable corrective actions; application of primer, paint, and compound as applicable; re-identification of certain part numbers; and marking of the modification status field of the nameplate of certain parts, effective Nov. 10, 2021.