That could mean joining Our Boys and Girls battling the Taliban after she steps down next July.
Kat, 22 - dubbed Combat Barbie after serving in Iraq - said she knew before getting the title that her Royal Anglian Regiment unit was due to serve in Afghanistan. Unfazed by the danger, she said: "It's something I want to do." And she added: "I'm not leaving the Army. I'll still be going to work."
Kat marked Remembrance Sunday with a two-minute silence with some of the 119 contestants vying to become Miss World.
The beauties met in London ahead of the contest's launch today.
Kat has been given five weeks off from Army duties to represent England in the final on December 12 in Johannesburg, South Africa.
She came runner-up as Miss England last July but was thrust into the role after winner Rachel Christie, 21, quit.
The Sun told on Saturday how she had allegedly fought with Miss Manchester Sara Beverley Jones, 24, over Gladiator love Tornado.
Kat, from Tunbridge Wells, Kent, admitted last night: "It's been an absolute whirlwind - in 24 hours my life has changed. It's been weird but fantastic weird because I really want this opportunity."
She added: "When I am a soldier I have my hair scraped back and no make-up. I hope it bodes well that I'm seen as a more natural beauty. Me having one day to get ready for this role shows that."