Finding four letters on your boarding pass could open you up to extra security checks at airports.
A travel expert has taken to social media to explain the four letters that might spell trouble for you if you see them on your boarding pass. If they appear, you may be subject to longer waiting times and security measures at the airport - reports the Daily Record.
Travel expert Michelle posted a video to TikTok to explain the meaning behind the letters 'SSSS' on your boarding pass. She explained the four S's stand for "Secondary Security Screening Selection", meaning you are likely to face extra security measures before you take off.
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The measures could include an additional pat down to check for security breaches or unusual items being carried. Additionally, travellers could also be subject to swabbing for explosive residue as well as opening up all of your bags to perform a thorough check.
Michelle explained in a video: "This is something you never want to see on your boarding pass: The quadruple S. It means you’re going to get searched super thoroughly, and it’s usually found on international flights to the US. The majority of passengers with the SSSS on their boarding passes are picked at random. However, those with the code on their pass are likely to be monitored by the US Department of Homeland Security."
Michelle explained how to clear up the problem, adding: "If you go to the US Department of Homeland Security website, you can apply for a redress number which prompts the DHS to review your record and clear up any erroneous or weird info that could be triggering the additional security measures. Once they’ve investigated your records and you’re hopefully cleared, you’ll want to input your redress number on all of your flight reservations going forward, and you should hopefully be good to go."
There are a number of other tell-tale codes that can be found on your boarding pass. For example, the two letters at the beginning of the flight number will relate to the airline you are flying with.
These codes are issued by the International Air Transport Association (IATA) - the trade body for international airlines. Codes include BA for British Airways, VS for Virgin Atlantic and QF for Qantas - all airlines have a unique code.
The numbers following these codes reveal a lot more information.
The general rule is the lower the number the more renowned - and often more longer distanced - the route. QF1 is for a Qantas flight from London to Sydney. Pilot Patrick Smith previously told news.com.au: “Airlines often give lower numbers to their more prestigious, long-distance routes,
“If there’s a flight 001 in an airline’s timetables, it’s the stuff of London-Sydney or Paris-New York.”
It is also worth noting whether your flight number is odd or even. Those with even numbers are flights heading east or north with odd number heading in a south or west direction - there are some exceptions to this one.
Weirdly, some flight numbers are influenced by superstition. The number eight is considered lucky in many Asian cultures so is therefore likely to be included in most Asian routes. United Airlines’ flight from San Francisco to Beijing is UA888.
Rarely seen numbers include 13, 666 and even 911.