5 April 1968 – To protest the lack of an aerial display to commemorate the 50th anniversary of the founding of the Royal Air Force…and to demonstrate against the government of Prime Minister Harold Wilson, Flight Lieutenant Alan Pollock of the RAF’s No. 1(F) Squadron makes an unauthorized display flight in a Hawker Hunter. This became known as “The Tower Bridge Incident”.
Pollock decided on his own initiative to mark the occasion of the RAF anniversary with an unauthorized display. His flight left the soon-to-be-closed RAF Tangmere in Sussex to return to RAF West Raynham in Norfolk, a route that took them over London. Immediately after takeoff, Pollock left the flight and flew low level.
Having “beaten up” Dunsfold Aerodrome (Hawker’s home airfield), he then took his Hawker Hunter FGA.9 (XF442), a single-seater, ground-attack jet fighter, over London at low level, and circled the Houses of Parliament three times as a demonstration against Prime Minister Harold Wilson’s government. Pollock continued and dipped his wings over the Royal Air Force Memorial on the Embankment, and finally flew under the top span of Tower Bridge He later wrote of the decision to fly through Tower Bridge:
“Until this very instant I’d had absolutely no idea that, of course, Tower Bridge would be there. It was easy enough to fly over it, but the idea of flying through the spans suddenly struck me. I had just ten seconds to grapple with the seductive proposition which few ground attack pilots of any nationality could have resisted. My brain started racing to reach a decision. Years of fast low-level strike flying made the decision simple…”
Knowing that he was likely to be stripped of his flying status as a result of this display, he proceeded to “beat up” several airfields (Wattisham, Lakenheath, and Marham) in inverted flight at an altitude of about 200 feet en route to his base at RAF West Raynham, where, within the hour, he was formally arrested. He was subsequently invalided out of the RAF on medical grounds. This avoided a court-martial and the embarrassment to the government of Pollock giving a reason for his stunt and perhaps receiving the support of the public.”
Although other pilots had flown under the upper span of Tower Bridge, Pollock was the first to do so in a jet aircraft.” (1)
Source: Wikipedia
Note: I know that no F-100 pilot would ever consider flying under a bridge.