A French fireman stands in a gymnasium near maps that show the terrain where an Airbus A320 crashed in the French Alps, near Seyne-les-Alpes, March 24, 2015. [Photo/Agencies]

Tuesday's crash came less than three months after 162 people were killed in December last year, when another A320 run by budget airliner Indonesia AirAsia went down in the Java Sea. The crash is still being investigated.

The Germanwings aircraft was delivered to Lufthansa from the Airbus production line in 1991 and transferred to Germanwings in 2014, and media reports said it was one of the oldest planes in the airliner's fleet.

According to data from the Aviation Safety Network, A320 is one of the world's most used passenger jets and has a good safety record.

Germanwings, which has a fleet of around 78 aircraft flying to 130 destinations, plays a key role in Lufthansa's effort to compete against other low-cost carriers in Europe.

Budget airlines, which have won a major share of the European aviation market, have been able to offer low ticket prices as they have squeezed down other costs, by eliminating or charging for services such as meals during flights, as well as reducing ground staff.

Experts say the airlines have rarely been involved in accidents and are subject to the same safety and maintenance requirements in line with aviation standards.

It was too early to speculate on the cause of the crash, although accidents during the cruise phase of the flight are rare, they noted.