According to The Associated Press on July 9th, U.S. President Donald Trump returned to the United States in the old version of the 'Air Force One' aircraft after attending the NATO summit in Turkey, instead of the new aircraft gifted by Qatar and modified for his use upon arrival.
According to reports, on the evening of the 6th, Trump flew the newly modified Air Force One throughout his return flight. However, at the end of the summit on the 8th, he changed his schedule temporarily, abandoning the new aircraft and flying the old Air Force One back home. Meanwhile, both aircraft arrived at the Royal Air Force Base in Mildenhall, England. Subsequently, Trump transferred to the new Air Force One again at the base and returned to Washington.
This unexpected change in the special aircraft occurred while the United States and Iran resumed mutual air strikes. This has also raised concerns about security. Pictures show that this special aircraft, gifted by Qatar, is not equipped with certain missile detection and countermeasure systems.

Trump Arrives at U.S. Military Base in Britain – Associated Press Video Screenshot
According to sources familiar with the situation, given the escalating situation in Iran, the US Secret Service recommended that Trump make an emergency flight change. However, this was a preventive security measure, not due to any specific threat of attack. To ensure the president's safety, passengers traveling with Trump were also asked to pull up the window shades during their flight out of Ankara.
Trump did not give a clear response regarding the temporary change of aircraft, but stated that he would fly in an old-fashioned plane 'for nostalgia'.
During the flight, Trump denied to reporters accompanying him that the change to a different plane was due to concerns about security threats from Iran. When asked whether he knew of any credible threats from Iran against Air Force One, Trump avoided answering the question.
I have always been a target of threats; I am one of their top targets on the list," he repeated, echoing what he had said eight days earlier, calling himself "one of Iran's main assassination targets."
According to the Associated Press, Iran possesses various missiles and drones with ranges sufficient to reach Turkey from its borders. However, according to the US think tank Center for Strategic and International Studies, Iran does not have weapons that could effectively strike targets in the UK, with a range of 4,000 kilometers.