Summary
We propose to adopt a new airworthiness directive (AD) for certain Bombardier, Inc. Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes. This proposed AD was prompted by reports of two in- service incidents where the left main landing gear (MLG) failed to extend. This proposed AD would require installing stopper plates on the aft uplock frames in the MLG bay adjacent to the right and left MLG uplock assemblies. We are proposing this AD to prevent incorrect installation of the upper bolt in the MLG uplock assembly, which could prevent the MLG from extending and adversely affect the safe landing of the airplane.