Pilots' union Cockpit toured the country's airports checking to see if operations were up to scratch, Die Welt newspaper reported.
They said that five airports – Weeze, Memmingen, Lübeck, Zweibrücken, and Friedrichshafen did not meet their safety standards. The union's complaints include a lack of pathways to taxi airplanes and poor approach lighting for pilots coming in to land.
While Cockpit's definition of "serious safety defects" is stricter than general international standards, the union said "a rich industrial country like Germany should not align itself with international minimal limits," but rather set its own criteria.
The union was known among airports, said Die Welt, for being particularly strict in its judgement. Lübeck airport released a statement saying it was not possible to fulfil all of Cockpit's criteria.
Friedrichshafen called the inspections arbitrary, while Memmingen, in southern Bavaria, disputed the fact that not having enough taxi pathways was a safety issue.
Yet Cockpit found no faults with Berlin Schönefeld, Düsseldorf, Leipzig/Halle, Munich, or Stuttgart. A few issues were flagged up in Erfurt, Frankfurt/Hahn, Frankfurt/Main, Karlsruhe/Baden Baden, Cologne/Bonn, Westerland and Nuremberg.