Sara Gallienne had not realised the blade was in her luggage until she got home.
But that hadn't stopped her successfully carrying it through TSA checkpoints at both Richmond and Providence, Rhode Island.
I was going through it (bag), pulled out my headphones and I realised, "Oh crud. I have a knife in here,"' Ms Gallienne told WTVR News.
'I was blown away I could not believe that I had just made it through with this knife. Not one, but two TSA checkpoints,' she added. Read more:
The Legend of Popcorn Sutton
The Police files
Ron Paul is the only "electable" Republican
Tyranny and Nullification
Simply voting out Obama is not the solution
State Governments say they own the rain and if you steal it you could be arrested