Despite the stringent security measures in place across the aviation industry, incidents of passengers boarding flights without tickets continue to occur. A notable case involved a woman who managed to board a Delta Air Lines flight to Paris without a ticket. This issue is not confined to the United States; Zurich Airport has also reported multiple cases of unticketed passengers boarding aircraft.
According to Swiss Info, Zurich Airport experienced one such incident in 2023, which increased to four by 2025. In June 2024, a woman boarded a flight but was discovered during a headcount conducted by the cabin crew. Bettina Kunz, spokesperson for Zurich Airport, stated: "On this plane, people were counted upon boarding, and if the headcount or recount of heads doesn’t match the paperwork, a check is carried out to determine whether there are too many passengers on board."
The same woman attempted another unauthorized boarding weeks later but was caught again due to an onboard headcount. Another passenger claimed he boarded without a ticket as an experiment to test airport security.