Basing their work off of a paper published in 2011 called Trajectory of a Falling Batman from the Journal of Physics Special Topics, the writer applies a number of models and equations to what we see during the brief scene in the trailer to determine how Spidey is able to get the lift and glide he’d need to coast on his wings. They also take into account the real-world example of skydivers who use wingsuits to achieve a similar result. These were likely an influence on the design for the film, as Spider-Man’s web wings in the trailer are considerably larger than they appear in the comics. While Wired doesn’t answer the question of believability, they do provide the tools to understand the forces at play for the mechanism to work.
This tech could come in handy when Squirrel Girl joins the MCU and is looking to further emulate her furry friends. Hopefully, Tony will have her back with a similar deal when that happens. Fingers crossed for a film starring Spider-Man, Squirrel Girl, and Iron Man in our future.