Yes, we do. But there are many things we look for when passengers are boarding an aircraft.
Prior to passengers even boarding the aircraft, the lead flight attendant,(sometimes called the senior, or for my airline the purser), is given paperwork covering many things. Depending on whether we are domestic or international, will depend on the extent of the information.
It lists all passengers, names, seat numbers, if they are a priority member, what class they are sitting in, what type of travel they are on(they may be an airline employee, etc.), are they a federal Air Marshal? If so, all other crew members need to be informed and confirm information with the captain (who should already have this information.)Also, many more things like the type of food, amount per type, if it’s, our duty-free items, customs info,… so basically everything.
Many things are being “ticked” off on a mental list as you board.People requiring extra assistance with children, or elderly. Someone requiring a wheelchair or perhaps oxygen onboard. (you may notice two flight attendants on larger aircrafts standing at the door? This is so if the Purser needs assistance, he/she doesn’t need to leave the door. They can have the other flight attendant help them with whatever they need.)
So we are watching for all of this, but all the flight attendants should have been made aware of as much of this in a pre-flight briefing. Which is required to include all the flight attendants. (and the captain if possible).
We do look for red flags. There are specific things at certain times we look for.
I flew the first int’l Flight out of Seattle, Wa. after 9/11…and had a suspicious man on board that fell under certain criteria.
After being questioned, he was allowed to remain onboard without incident.
So notice, yes..lol. Everything. Even if you are wearing sandals flying into Minneapolis, MN in the dead of winter sometimes.
That will definitely get our attention AND a medal for bravery!