The Mayor's Ambient Noise Strategy - Greater London Authority

The Mayor’s Ambient Noise Strategy Mayor of London 141
of the Thames through central London. Twin-engined machines have more
freedom to take the most direct route. The limited number of routes
available to single-engined machines can become heavily used during
some periods. In certain areas, such as Greenwich, helicopters may be
held for air traffic control reasons, which can create additional disturbance
as machines circle.
4C.50 Existing helicopter routes have been designed taking account of flight
safety and operational aspects of integration with other traffic flows. They
tend to follow open spaces where available. This minimises the residential
population overflown, though it reduces open space tranquillity. For
example, the Barnes Wetlands wildfowl centre is located at a junction
between helicopter routes. The corridors used are in practice some half a
mile wide, which reduces the concentration of highest noise levels in
many locations. Helicopters may not fly closer than 500 feet to any
person, vessel, vehicle or structure, except when taking off or landing.
The upper flying limits specified for helicopters are the highest practicable
to avoid conflict with aircraft arrivals and departures. Flying heights are
subject to weather and flight visibility requirements.
Figure 19 Helicopter routes across London
source: CAA - The UK CAA Aerodrome Charts manual (Extract from Airac 7 1999)
4C.51 People’s attitudes to helicopter use are likely to be influenced by how
essential they consider their use to be. It is not always clear to people on
the ground whether a helicopter is being used for air ambulance, or other
emergency services, for business, or for recreational purposes.
Helicopters are secured for emergency services under a variety of