It’s referred to as the “flying Pentagon”, but the United States’ nuclear proof airplane has been called into action as the President traveled to Europe.

The specially adapted Boeing 747 was designed during the Cold War as an aerial command post in case of a nuclear war.

If the President steps foot on this aircraft, chances are something big is happening.

Designed from the ground up when tensions were high between the United States and the Soviet Union. 

The Boeing 747 E4-B is fitted with nuclear and thermal shielding and is nicknamed both the Doomsday plane.

Officially called the Nightwatch, the aircraft has three decks and can hold a crew of 112 people and can fly for 12 hours without landing – but aerial refuelling means it can stay flying for days.

Its windows have wire-mesh to keep them in tact in the event of an outside explosion, and the wiring on board has been specially hardened.

While Air Force One has been designed for luxury and expressing soft power as the President travels the world, the Nightwatch is functional and designed for military use.

Inside it has 18 bunks, six bathrooms, a conference room and executive quarters.

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The bubble on top os called a ray dome and contains dozens of communications satellite dishes – putting the President in touch with any US ship, submarine or aircraft in the world.

Presidential escort

The Nightwatch has recently been spotted flying over Ireland, keeping a close eye on the President as he travelled to Europe.

This comes as Russian state TV warns any NATO intervention, even sending in peacekeepers to Ukraine, could be met with a nuclear response.

Russian President Vladimir Putin had previously placed his nuclear resources on full alert in an attempt to scare off the west from action.

All that puts the Nightwatch front and centre of the US military plans.

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