You might ask Siri for street directions on your iPhone, but voice control is also used by pilots to control sophisticated fighter jets.

The F-35, which cost a staggering $1 trillion (£585,000,000,000) to develop, has been on show at RAF Gloucestershire in the build up to the Royal International Air Tattoo.

Inside the cockpit are computers powered by 8.6 million lines of code that providing information to the pilot in two touchscreen displays, similar to the iPad.

The aircraft is powered using voice recognition - in fact it’s the same computer that runs Siri in an iPhone.

Billie Flynn, F-35 test pilot for manufacturer Lockheed Martin, refers to the cockpit as his workspace: “My work space is two iPads, Siri voice recognition and a helmet like Tony Stark in the Iron Man movies.”

Check out the video above to find out more.

High-tech helmets worn by the F-35 pilots include a built-in screen which displays key information such as altitude and navigation, along with images from six infrared cameras embedded in the skin of the aeroplane that enable the pilot to see through the plane.

“It makes me drastically more lethal and survivable. I see from horizon to horizon anything of contrast from the temperatures out there, I see objects in the air that would never have been visible otherwise” said Flynn.

Despite all the high-end technology in use, Flynn says the cockpit is very simple to use.

"There are less than 20 switches to touch - different than the fight cockpits of old because all I want the pilot to focus on is the information in front of him,” he said.

Ultimately the technology helps the pilot focus more effectively on his job: "The pilot's task is not flying the jet any more. His task is to go up and be lethal, be effective, in combat."

The RAF has ordered 14 F-35Bs at a cost of £2.5 billion to replace the already retired Harrier jets.

Update: Organisers have confirmed The F-35 will not be on show at the Royal International Air Tattoo. This follows concerns over the safety, following an engine fire last month.

Tim Print, Chief Executive of the Air Tattoo said: “It's not unusual for there to be delays in the development programme of any new military aircraft, and the Air Tattoo has been working closely with teams from Lockheed Martin, the US Marine Corps, Department of Defence and MoD to ensure the aircraft touched down at RAF Fairford for the Air Tattoo. Unfortunately we've simply run out of time."

A spokesperson for the Ministry of Defence said that the safety of pilots and aircraft was a  priority. “We fully support the decision not to grant clearance for the aircraft to make their first transatlantic flight to the UK until the technical investigations following an engine failure are complete."

Video credit: SWNS