Aircraft manufacturer Boeing announced on Thursday that around 50 737 NG planes have been taken out of service after cracks were found, AFP news agency reports.

The latest in a string of airlines to ground 737 NG planes is Australia's Qantas, which found cracks in the landing gear on one of its planes. The aviation engineers' union, ALAEA, has demanded that the company park all 33 of the model until the planes are inspected, The Guardian reports.

Shortly after the airline's announcement, Boeing itself said that around 5 percent of the total of 1,000 planes that had been examined had cracks, although the company did not want to give an exact figure, according to AFP.

The background to the large-scale inspections is that Boeing discovered severe cracks in the wing supports on ”a small number of planes” in early September. This prompted the US aviation authority, FAA, to urge the world's airlines to examine their 737 NG planes.

Among other things, SAS has announced that they have found cracks in two planes.

The NG model should not be confused with the modernized 737 Max, which is currently grounded from global air traffic after two accidents in a short period of time suspected to be caused by a faulty autopilot system.

Source: di.se