Moscow - Rostransnadzo, Russia's state transport agency, has ordered the country's airline operators to ground all Antonov An-148s. The measure followed the fatal crash of an An-148 from Saratov Airlines.

On February 11, an An-148 operated by the Russian low-cost had crashed soon after takeoff from the Moscow's Domodedovo airport, killing all 71 people on board.

The decision had been taken after an inspection at Saratov Airlines, said Viktor Basargin, head of the Rostransnadzor.

According to the Russian aviation authorities, there are doubts about flight safety of the type. At the moment, only Angara Airlines, Saratov Airlines, and Rossiya Airlines fly with the Antonov An-148.

In addition to the flight ban for the Antonov An-148, Saratov Airlines is not allowed to operate any flights until there is more clarity about the cause of the crash.

The preliminary conclusion is that the speed gauges of the crashed aircraft did not indicate the correct values, possibly due to the frozen sensors.

The Moscow-based Interstate Aviation Committee (MAK), a supervising body for use and management of civil aviation in the Commonwealth of Independent States (CIS), suggested that heating elements of the gauges were not switched on before the An-148 took off.

According to the flight recorders of the aircraft, two gauges displayed different speeds before the crash, one a speed of zero while the other rising rapidly.