Fog capital (London)

I worked on and off, 1985–1990, at a quango [quasi NGO]:  SBTC (Sino-British Trade Council), now CBBC (China-Britain Business Council).  

They offered a (then) free service to British companies wishing to do business with China, organising inward missions (Chinese delegations to the UK) and outward missions (British delegations to China).  

The Chinese have a nickname for London: wùdū 雾都 (fog capital).  We took great pains to tell them that such events were a thing of the past, the last one being the Great Smog (or the Big Smoke, which is London’s nickname) which took place in 1952.  

On the day this particular Chinese delegation was due to arrive in London, their plane got diverted to Manchester — because London was fogged out.

(Event happened 1985?/1986?)