He did board the older aircraft through its left-side door in front of cameras. Trump was secretly transferred back to the older Air Force One after reaching Britain. Iran Threat Triggered Secret OperationThe operation was reportedly put together within hours after US officials determined that a threat against Trump from Iran was credible. Reporters Kept In DarkWhen Trump arrived at the airport in Turkey, cameras captured him boarding the older Air Force One. The older aircraft landed at RAF Mildenhall in England at 10.16pm, according to the press pool report.