But when some passengers looked at the security cards in their seat pockets, they saw "737 MAX 8" on them and were worried.
Southwest explained each confused customer both aircraft types printed on the same card.
"Southwest currently offers an FAA-approved 737-800 and 737 MAX 8 security information card containing security information for both types of aircraft since the cabin configuration, number of seats (1
"All 737 MAX 8 aircraft are temporarily grounded, so customers will not travel on a MAX 8 aircraft while it is founded, Southwest says.
Other social media users chastised the confused passengers, noting that both types of aircraft were clearly printed on the card, and asked why they did not ask their airline companies to clarify rather than jump on social media and scare people.
Someone offered helpful advice, noting that you can look up the tail number on the airline's website to see what type of vessel you are flying, and encourage flyers to see if the wings matched the unique split design on a 737 MAX 8.
But southwestern customers were not the only ones asking questions. Passengers flying Norwegian Air had a similar experience. Norwegian Air responded to Twitter and assured passengers that it is printing security information for its 737 MAX 8 and 737-800 on the same card.