Given that the article refers also to Hawker Hunters and flying boats .. I thought I might mention that a Saunders Roe (Nautical) SRN4 hovercraft, The Princess Margaret, also 'flew' through the bridge in 1969:
Seaspeed's SRN4 'The Princess Margaret' passes through Tower Bridge during a promotional exercise along the Thames in 1969
In the video (at 0:42) a Westland Widgeon momentarily appears