It is known that there was a secret US project to make a massive dirigible, presumably supported by helium, and a massive hangar has been seen at a base. The concept was to transfer large numbers of troops with tanks, etc. However, this craft seen over Shawbury hasn't got the red and green lights which even US military aircraft have.
Who owned the craft?
Why would the US fly a craft like this at night over foreign cities? A large triangular UFO identical to the one seen at Shawbury was seen for several weeks over a Belgium town. Surely the US should have notified Belgium air control and police if it was their's? Both craft were silent.
Both episodes are probably hoaxes and mass-hallucination. The report that police in Belgium saw a UFO is true, but what they saw isn't verified. The subsequent reports from the public are probably just saying "Oh, I saw that too" after reading newspapers about the police report.
The above photos may be a hoax, but it is known that the USA have had tested large triangular craft, so the above craft which were seen frequently may be made in USA.