The captain eventually alerted the crew and was able to open the cockpit door, that's when the captain found the copilot asleep. The captain was able to land the Boeing 737 without further incident. Although in the incident happened in September, the Dutch safety board (OVV) released a report published on its website.

Dutch Safety Board spokesperson, Wim van der Weegen said "It's a serious incident. What makes it serious is the combination of the pilot being unable to access the cockpit and the first officer being asleep. By 'serious incident, I mean the flight was in danger.”  

The Dutch Safety Board reported it will respond appropriately to this incident upon completion Transavia Airline completes its investigation. The purpose of the Dutch Safety Board’s work is to ‘prevent incidents or to limit their after-effects’. Accordingly, the Board’s investigation aims not only to uncover the actual causes of incidents but also and in particular to bring to light the underlying causes of the incident, so that any shortcomings in the applied system can be revealed.