Originally Posted by
Andy33
However I've yet to find one that allows someone who has arrived from outside the Schengen area (remember the OP is coming from LHR) to get into the airside Schengen departures area without a boarding pass.
Not that hard to find, e.g. try CPH. Once you clear immigration/passport control you are airside in the main Schengen terminal, no boarding pass needed (as long as you come from a secure point of origin, otherwise they'll send you to the baggage claim).
Same goes for a lot of other airports around.