Check with your airline, but I think a knife in luggage that goes in the hold is okay. Was when I've done it. But also check the state laws where you're going.
I'd certainly take a couple of Swiss Army knives and a sheath knife with a five or six-inch blade. You shouldn't be on the trail without them.
My scariest moment was pre 9-11-01, but there were already knife regs about what you could carry on your person. I had a German lockblade folder in my pocket by my wallet. Four-inch blade, stag handle. Henckels Twin Works, with a saw blade and corkscrew as well as the main blade. I had checked my S&W M-36-1 (nice smooth rosewood Magna stocks and a Tyler adaptor) in luggage, but had forgotten that knife.
I caught a SW Airlines girl, explained my dilemma, and she graciously took my suitcase key, found the suitcase, and opened it to slip in the treasured knife. She was both lovely and helpful.
The last time I flew with a knife on me was in summer of 2000. I was at a Zeiss optical seminar in Virginia, flying to and from Texas. No problems with a normal Victorinox Spartan SAK. I just showed it with my other pocket litter and the agent passed it, although one in, I think, Philadelphia, looked disparagingly at it. But it was below the legal limit then. My Buck Model 105 sheath knife went in my checked luggage, no problems. But the world has changed, and not for the better in that regard.
I suggest that you take a book on backpacking and maps of the area where you're going, and a compass. Those items will support your story that you need the knives on the trail. That may give them respectability in the doubting mind of a low tolerance cop or TSA examiner.
