Antonov 26
 

There are quite a few of these turboprops in western Europe. Is it true that they will have to go soon, due to noise restrictions or other requirements?

Don't know about the prop planes, but aircraft such as the IL-76 are on the chopping block. Stage 3 and all that...

some of An26, especially east-european registred (not RA, UR), are stage 3 certified with some penalties on performance. usually stage 3 on an26 assuming that they do not use APU power on take-off (on an26 APU is adding takeoff performance), plus some tricks with flap settings. so you may expect to see them around for next several years.