The bottom line with all this is that the 146 costs 4 times more in maintenance than modern a/c such as the later 737s and 319/318s. For that reason alone it must be replaced sooner rather than later. What with? - no idea but the Co has often said that it needs a 110/120 seat a/c as it can't run the network efficiently with just a 78 seat one and a 150 seat one.