Spectre trailer: How did they do that helicopter roll?

The helicopter barrel roll is the most spectacular thing in the new Spectre trailer, and an aviation expert has confirmed it is perfectly possible.

Mike Buckley, a helicopter pilot and spokesman for the British Airline Pilots Association, identified the helicopter as a BO105.

"It is possible to fly a helicopter upside down for a short period of time," Buckley said.

"Helicopter pilots are highly trained and this footage appears to be a BO105 undertaking a very skilled manoeuvre with an expert pilot at the controls.

"The BO105 has a rigid roto head which makes it possible to fly some amazing routines. The Westland Lynx, as flown by the UK Army Air Corps and the Royal Navy, also has a rigid head and is often seen in air shows around the UK doing rolls an occasionally loops.

"Clearly 007 has been through rigorous training to achieve his licence and learn how to safely complete this type of move..."

However, everything may not be as it seems. Buckley added: "It's difficult to tell if this footage is of a real flight or a CGI recreation. They may have filmed a real flight and tinkered with the images afterwards.

"There are strict rules about low flying, so if it is real footage the backdrop may have been added later to make it look more dramatic."