The Dutch safety board has carried out two investigations into ‘serious incidents’ at Amsterdam’s Schiphol airport in the previous three months, the Parool said on Tuesday.

In one incident on April 21, the tail of a plane hit the ground during take-off, prompting a return to the airport after first dumping tonnes of fuel above the North Sea.

In the second incident, an aircraft was cleared for take-off even though a member of the ground crew was in his vehicle checking for birds on the runway.

The OVV is required by law to investigate all incidents involving aircraft on the ground or in Dutch airspace.  Despite the investigations, the board said there are no indications that safety standards are insufficient.

Nevertheless, in April, the board published a report stating that Schiphol airport cannot grow without taking drastic safety measures. The report warns that the ‘limits of safe air traffic control are in sight’ and that if the airport wants to grow, handling procedures must be far less complex.

That report was the result of several incidents at the Netherlands’ major airport, including near-collisions between planes, but the board then too found ‘no evidence that the airport is currently unsafe.’