Used to be good times at EMA as a kid with the viewing area looking out at the TEA uk, Britannia, Air Europe etc jets.
Birmingham had the viewing area in the terminal also and Heathrow on top of the Queens Building. Shame I can't take the kids to these places, yet when we went Vienna and Amsterdam these area's still exist and are actively encouraged with tours etc.
Manchester and EMA at least have the viewing parks I guess... Heathrow have that tiny stand outside the Renaissance!