Brittany Cartwright Struggles to Jump From Helicopter on 'Special Forces'

Brittany Cartwright is facing her fears head-on in "Special Forces: World's Toughest Test" ... but not without a serious struggle when it comes to jumping from a helicopter.

TMZ obtained an exclusive clip from tonight's episode showing "The Valley" star battling major nerves as she prepares to make the leap. With the chopper blades spinning overhead, Cartwright admits just how overwhelming the moment feels, telling the camera how terrified of heights she is.

In the clip, she hesitates, inching toward the door, desperately clinging to the rope as she hangs over the helicopter skids, unable to let herself go, as the guy in charge yells at her to  "Go, go, jump!"

She explains, "I'll walk on a balcony in a hotel with my back up against the wall so that I don't have to like get close to the edge. But no matter what, I'm really dedicated to trying every single thing that comes my way."

Cartwright is among 18 celebrities taking part in the grueling FOX series, which drops stars into Morocco to endure extreme challenges modeled after military training. This season's recruits include Teresa and Gia Giudice, Johnny Manziel, Jessie James Decker, and Jussie Smollett, all of whom must push past their breaking points with no eliminations ... only survival.

For Cartwright, the helicopter challenge may be her most daunting test yet, but the sneak peek makes one thing clear ... even with her fears on full display, she's determined to push through.