Once again, this was an advertisement from a 1971 issue of The Economist for an airline which no longer exists. Are you ready? Scroll down!
British European Airways advertisement titled: ‘BEA. Right to the heart of Eastern Europe’, featuring an airliner landing in the Red Square in Moscow.
The introductory text said that the airline no longer exists, which means that it couldn’t possibly be Aeroflot. Plus, it was a Hawker Siddeley Trident operator. I think that alone was sufficient to guess that it was British European Airways (BEA), which merged with British Overseas Airways Corporation (BOAC) in 1974 to become British Airways.