Prime Minister David Cameron officially open the show.
Sir Richard Branson is at the show to order 12 Airbus A350’s worth around $4.3billion.
The passenger plane is environmentally friendly burning less fuel and making less noise. They will fly from Gatwick and Heathrow.
Around half of it is built in the UK, including wings and engines, with final assembly in France.
However the future of Airbus in the UK has been questioned by some following the Brexit vote.
Airbus is a company with bases all over Europe employing 60,000 people and it is not clear how much of the operation would continue here long-term.
The show is expected to attract 100,000 people from every part of the world with 1,500 companies exhibiting both military and civil aviation. Monday to Friday is for the trade with the weekend seeing public days.
New safety rules following Shoreham means the flight display area has been moved further away from spectators and some roads will be closed.
Star of the show will be the new F-35 fighter aircraft