Mate - go and have a look at the LHR AIP (or if you feel brave come and plug in at CF62!!!)
The Helicopter route H9 does cross right over LHR* - and the route altitudes are up to 2000ft. AND guess what..... the crossing level is level at 800ft! (be it police or PPL fliers)
*Via the thresholds but you start and finish north or south at the midpoint of the field
£99 is a bargain - especially as if you let us know if a PPRUNEr is on board - we will delay you and make it up to 60 mins!!
Anyway - nothing new in this - weekends see up to 8 operators operating pleasure flights in the zone - over central London and LCY/LHR/Northolt. (Each operator does as many as a dozen flights, from airfields like Booker, Elstree, Stapleford, Redhill North Weald, Duxford, even Manston)
We even get some helicopters doing this in and out of Battersea.
Some pics from a LHR crossing I took previously:
