How Do You Add TSA PreCheck® to EL AL Airlines? To add TSA PreCheck® to your EL AL Airlines booking, follow these steps: When booking your flight, ensure you enter your Known Traveler Number (KTN) in the appropriate field on the airline's website or during check-in. If you've already booked, you can usually add your KTN to your reservation by visiting the airline's website and entering your confirmation number and last name. This will allow you to enjoy expedited security screening at participating airports when flying with EL AL Airlines.