Maybe you've noticed that you don't see old school 737's (100s & 200s) and you don't see anymore 727s either.
Stage 2 (noise compliant) airplanes are no longer legal to fly in the US. Were the FedEx 727s (with the hush kit engine mods) Stage 3?
I thought that after 9/11 FedEx traded United hush kits for DC-10s? We've flown those old airplanes a long time.
