They'll be going soon. In the EU first and second generation jets are almost non-existent. By first and second, I mean the 707 and DC-8 as first, and the DC-9, 727, and 737 as second generation.
I think the smaller airlines are going to have a problem soon. Where are airlines like Vanguard going to get the money to replace their fleet of 737-200s? What's going to happen to airline subsidiaries like Delta Express and Metrojet? Are these divisions profitable to warrant new Boeing and Airbus fleets?
I think airlines like Southwest have been anticipating these newer, stricter rules and have had the foresight to over time introduce newer fleets of planes, like the 737NG.
And cargo airlines like FedEx and UPS, who have large fleets of the versatile 727F. Where are they going to find a comparison? Maybe UPS can order more 757Fs, but where is FedEx going to find a plane? It seems that when these rules, most likely to be named Stage IV, go in to effect in a few years, many airlines are going to find it hard to meet these stricter standards.
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