Helipad Ec1
OK Guys and Gals, some FACTS.
In addition to the London Hospital, Whitechapel - still active for London HEMS - there were three roof-top helipads operational some 20 years ago.
One was on top of the International Press Centre from where the old style newsprint presses were flown overnight to enable printing at other newspaper presses around the country. Although I believe it is still there memory (admittedly not what it once was!) suggests that the last time it was used was several years ago for a Rowan Atkinson credit card advertisement.
The second was on top of Robert Maxwell's office block, next door to the old Mirror Group building. Used regularly by the old villain's Twin Squirrel while he was alive - and again still visible from above - it is, to my knowledge, no longer active.
The third, close by across Holborn Viaduct, is still operational by a private owner. Some reading this will know more details, many will speculate. I believe in an individual's right to privacy. This particular helipad has been in operation for well over 20 years and is approved by the Civil Aviation Auhority Aerodrome Standards section of the Safety Regulation Group, having fully met the required safety standards.
The owner of the Harrod's building did indeed commission a helicopter pad for the roof in the mid 1990's. A full and thorough study was carried out and a safe design, including full fire and rescue equipment, approved and constructed. Trials were conducted using a Twin Squirrel helicopter and these included noise recordings taken at street level at various locations in the surrounding area. Despite the noise of the helicopter being less than that of the general traffic - and therefore failing, pretty much, to register, such was the lobbying strength of local residents - just check the price of properties in and around Sloane Square - that "Change of Use" planning applications were unsuccessful. So there it sits, ready to go but un-used.
All air traffic within the London Heathrow Control Zone is controlled by ATC. Any aircraft wishing to enter the zone will require clearance to do so, either IFR - eg scheduled aircraft in and out of LHR - OR Special VFR. For SVFR there is a dedicated team of controllers who become extremely good at their job. Invariably helpful they are able to monitor individual progress and WILL advise you if you stray more than a few metres from the designated routes.
Long-winded, I know, but perhaps useful to answer some queries and to end unhelpful speculation.