Airbus has unveiled a possible mega-order for its planned new eco-conscious A320neo jet - a deal the European aircraft manufacturer is calling the largest in aviation history.

The commitment by Indian low-cost carrier IndiGo for 180 A320s - including 150 of the new A320neos - would have a value at list prices of 15.6 billion US dollars if converted into a firm order, Airbus said.

Airbus said it would be the biggest order in terms of number of jets in aviation history.

The deal won applause from industry analysts.

"It's a great win," said Joseph Campbell, a New York-based aerospace analyst at Barclays Capital.

"It's just where you'd think it would come from, from one of these emerging, fast-growing markets and a fast-growing airline ... It's perfect."

IndiGo is the first announced customer for the A320neo - a revamped version of the European aircraft maker's workhorse jet that Airbus hopes to bring to market in 2016.

New features include more fuel efficient engines and other technological features with the goal of fuel savings of 15% over its predecessor.

The new aircraft is also being designed with lower carbon emissions and engine noise in mind, Airbus said.

The A320 is Airbus' best-selling plane. Over 6,800 have been ordered and over 4,500 delivered to more than 310 customers worldwide since the single-aisle plane went into service in 1988. It was designed to compete with Boeing's 737 family, which has been running since 1968.

The announcement followed recent negative publicity for the European consortium.

On November 4, a Qantas A380 superjumbo - Airbus' star plane - made a safe emergency landing in Singapore in what was the most significant safety issue yet for the giant jet since it began passenger flights in 2007.

An oil leak had caused the plane's Rolls-Royce Trent 900 engine to disintegrate in mid-air. Airbus said Rolls-Royce is installing a software fix so the engine will shut itself down in case of problems.