The budget airlines that have won a major share of the European aviation market are subject to the same safety and maintenance requirements, experts said Tuesday, and have rarely been involved in accidents.
The crash Tuesday in the French Alps of an Airbus 320 operated by Germanwings, the low-cost unit of Lufthansa, killing all 150 on board, was only the second accident involving a budget airline in Europe.
A Boeing 737 operated by the Cypriot company Helios crashed in Greece in 2005, following a breakdown in the oxygen supply, killing all 121 on board.
Following the deregulation of the European air travel in the early 1990s, budget airlines have swooped up 30 to 40 percent of the market in medium-range flights, according to Bertrand Mouly-Aigrot, an air transport specialist at Archery Strategy Consulting.
Low-cost pioneer Ryanair, with its fleet of 300 Boeing 737s, has become one of the major players in Europe, operating 1,600 flights daily serving 186 airports in 30 countries.
Its British rival EasyJet, which will soon have 226 Airbus A320s, operates an average of 1,400 flights each day.
These two companies, and more recent emulators such as Air Berlin, Vueling, Norwegian and Wizz Air, have forced traditional airlines to adapt or face being squeezed out of the medium-haul market.
Lufthansa shifted its European flights to Germanwings except for those serving its two biggest domestic hubs Frankfurt and Munich, including the flight from Barcelona to Duesseldorf that crashed on Tuesday.
IAG, which owns British Airways and Iberia, has snapped up Spanish-based Veuling.
Air France-KLM has been trying to expand a low-cost subsidiary, Transavia, although pilots unions have slowed its development.
- Low cost not low safety -
Before the Germanwings crash, the reasons for which are not yet clear, European budget airlines had prided themselves on their safety record, and had even used it as a selling point.
Ryanair and Easyjet also boasted about how the planes in their fleets are new, which is part of their business strategy, noted Xavier Tytelman, an air safety specialist.
New aircraft are more efficient, giving airlines who use them a major cost advantage as fuel can account for a quarter to half of operating costs.
But new planes can also mean lower maintenance costs. Each four or five years passenger jets require an extensive overhaul, which is both costly in itself and requires taking the plane out of service for weeks.
"Low-cost airlines don't have any incentive to invest in such maintenance and just before planes arrive at that age they sell them," Tytelman told AFP.
However the Germanwings A320, which had earlier served in Lufthansa's fleet, was 24 years old.
That makes it "relatively old, and probably in its final years of commercial service," said Mouly-Aigrot.
"But pulling the oldest planes out of commercial use is a question of economics ... not a question of safety," he said. "Old aircraft cost more to operate and are less efficient."
Whether they belong to low-cost or traditional airlines, aircraft are subject to the same maintenance rules.
"Low cost, that means less comfort, but not less safety," said Tytelman.
Budget airlines 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.
Germanwings enjoys an excellent reputation in European civil aviation circles, the two experts said.
"It is a Lufthansa subsidiary, the top European air group, which has a reputation for being dependable and reliable, and which also owns one of the biggest aircraft maintenance companies, Lufthansa Technik, that maintains planes for dozens of airlines across the world," said Mouly-Aigrot.