PARIS (REUTERS) - The Airbus A320 is the workhorse of Europe's aerospace industry, transporting more than a million people a day from business travellers to backpackers.
The 150-seat medium-haul jet is one of the world's most intensively used together with its main rival, the Boeing 737.
The Germanwings aircraft that crashed in the French Alps on Tuesday, killing all 150 people on board, was also flying on the industry's most widely sold engines, made by French-US venture CFM.
More than 3,600 of the jets are in operation and another 3,700 are waiting to be built as Asia's economic expansion fuels record demand.
Put together with the rest of the A320 family of twin-engined, single-aisle jets - the A318, A319 and A321 - more than 6,000 are in use several times a day, whether feeding passengers into hubs for traditional carriers or fuelling the growth of low-cost airlines.
Experts say its safety record is among the industry's highest, but it made grim headlines in December when an Indonesia AirAsia A320 plummeted into the Java Sea, killing all 162 people on board. The crash is still being investigated.
To airlines, the main value of the US$97 million (S$130 million) jet is reliability and quick turnarounds, features it shares with the rival 737.
But it made dramatic headlines in 2009 when a US Airways jet ditched safely in the Hudson River after a bird strike.
"The A320 family has a very good safety record considering that there is a fleet of... 6,000 aircraft out there," said Paul Hayes, safety director at British consultancy Ascend.
Boeing statistics for its rival's best-selling model show that up to end-2013, there were 0.14 fatal A320 accidents per million departures where the plane was destroyed or written off.
The comparable versions of Boeing 737 had a rate of 0.11 per million departures, making them both among the industry's safest models compared with the industry average of 0.76, or more than 4.6 for the earliest days of the jet age.
At 24 years old, however, the A320 that crashed was at the upper end of the ages of jet used by many first-tier airlines.
BUILT TO LAST
Jetliners are built to fly safely for considerably longer but most major airlines sell them sooner for economic reasons.
"There are many airliners out there older than this that are flying safely," said Jim Morris, partner in UK law firm Irwin Mitchell.
Germanwings parent Lufthansa recently placed orders for over 100 new A320s.
To ordinary passengers, the A320 looks much like other jets.
But in the cockpit it represented a revolution when it began service in 1988 as the first "fly-by-wire" jetliner relying on computers to fly within safe limits and replacing the usual control yoke with a side-stick, inspired by the F-16 fighter.
The increased reliance on computers, though increasingly common across the industry, prompted a bitter debate between Airbus and pilot unions over whether too much control was being taken out of human hands. The argument rumbles on to this day.
Safety experts said it was too early to speculate on the case of the crash, but noted that accidents during the cruise phase of the flight are rare, even though this comes less than three months after the AirAsia disaster.
"We have had a couple of events recently but in general jetliners don't crash during the cruise," said Hayes.
According to separate surveys published last year by manufacturers Airbus and Boeing, only 10 to 12 percent of fatal accidents take place when the aircraft is at cruise height.