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In a short time from now the civil licenced helicopter will be required to include among its capabilities the ability to operate in Instrument Flight conditions to lower limits than those currently laid down for fixed-wing aircraft operations
At the moment I estimate that the problem is roughly half solved and, if there is a helicopter suitable for city centre operations by 1961, the aids and equipment under development should be able to give safe flight conditions in 150 feet ceilings and 150 yard visibilities