that's the boarding a plane one.
Light is correct, it was indeed the myth about boarding a plane that can be glimpsed in the sneak peek video.
This episode was broadcast in Australia and the UK between September and October 2012. But will only be broadcast in the US on 25th January 2014, even though it was included in the sneak peek video for the early 2013 season - Adam even mentioned it as one of his favourite episodes when they were promoting the show back then.
Discovery have posted a list of upcoming episodes, some of which you might recognise from TC;
Star Wars Special
Moon Shiner myths (11 Jan)
Hollywood car crash Cliches (18 Jan)
Plane Boarding/Bite the Bullet (25 Jan) {Note; Bite the bullet is about making bullets from teeth)
Car Chase Chaos/Animal Antics (1st Feb) {Note; The animal antics myth is about ways to deter animals and has nothing to do with the animal myths thread posted on TC)
Laws of Attraction (15 Feb)
Do try this at Home (22 Feb) {Not posted as an idea on TC, but it has been brought up multiple times on Discovery and the 'Young Scientists Corner' was based on this idea}
Supersonic Ping Pong/Ice Cannon (1st March) {Both were posted on TC}
dsc.discovery.com/tv-shows/mythbusters/2014-episodes.htm