Some statistics indicate as much as 35 percent of flights in Europe are illegal charter flights–although EBAA puts this number at about 12 percent–but “the truth is nobody knows,” Aoife O’Sullivan, partner at law firm Gates and Partners, said yesterday at EBACE during a panel discussion about the problem.

It is well over a year since EBAA launched a campaign for operators, brokers and passengers to curtail illegal charter flight activity within its borders, but the initiative seems to have made little headway against widespread abuses. Since then, actual numbers of illegal operators caught in the act have been extremely low. In the UK, there were no prosecutions last year, despite the country being one of the three biggest users of private aviation in the EU.

There are several reasons, the panelists said. First, it is virtually impossible to check which flights are operating commercially without a valid air operator’s certificate (AOC). More pertinently, European laws are so complex that many people do not even realize they are breaking the law. For example, swapping a hotel room for a seat on a flight would render the trip illegal in some European countries if it were operated under Part 91 regulations.