Using a very close approximation of the Ferris Air logo from 2011's Green Lantern movie, the poster boasts "we fly without fear," a nod to one of the requirements to be a Green Lantern: the ability to overcome great fear.
It originated as a tweet from Arrow Executive Producer Marc Guggenheim, who co-wrote the Green Lantern film and served as a producer on it, along with Arrow showrunner Greg Berlanti. For Guggenheim's part, he identified the graphic as an Easter egg.
#Arrow easter egg preview… pic.twitter.com/x8apvpZZfh
— Marc Guggenheim (@mguggenheim) April 10, 2014
That makes sense, in that earlier this year we saw a similarly-shaped Easter egg: an ad for the Blue Devil movie on the side of a moving bus in the midseason premiere episode, "Blast Radius."
Last year's season finale of Arrow featured Eddie Fyers threatening to shoot a Ferris Air jetliner out of the sky, so this wouldn't be the first reference to the organization, which is run by Carl Ferris and his daughter Carol, who is Green Lantern's long-time love interest and occasionally the supervillain/antihero Star Sapphire. In the film, Carol was played by the hit CW Network series Gossip Girl, which also starred Willa Holland, who plays Thea Queen on Arrow.
In the comics, of course, the friendship between the fiery, liberal Oliver Queen -- who gets by on grit, skill and resources -- and staid, conservative Hal Jordan, whose incredible powers come from the most sci-fi-heavy weapon in DC Comics is legendary.