Number one rule of travel. Take nothing you aren't willing to lose.
“Open, close, cut, clean, oil, cut, cut, cut... To a Spyderco, that is living. Letting it die in the box is to lose 75% of what we put into it." -----Sal Glesser
My wife had a nail file (one of the metal ones with a pointy tip) in her check in luggage on one trip (SFO) and (I assume) TSA took it!!!
I carry spydies all to the time for travel. And since I live in Indy ( the burbs) you are good to go up to about 4 inches here on a folder.
When I flew to Boston in 2009 I put my knives (cheapos at the time) into my pants pockets in my checked luggage then folded my pants, pocket toward the inside of fold. didnt have any mishaps.
Our Freedom, you want it, Come and take it.
Joshua 1:9b "Be strong and courageous, do not be terrified, do not be discouraged, for the Lord your God will be with you wherever you go"
And, like LC Kid, at one time I traveled a lot. At least twice a week. I learned the #1 rule mentioned by Zatx. After many mishaps (lost luggage, stolen stuff) I started traveling with only a carry on and computer case. Nothing gets checked in. Ever. Too much stuff? Ship it ahead.
As far as knives go, what I do today is to ship ahead or (my personal favorite) add a trip to a sporting goods or knife store into my agenda. I then ship the knife home after using it for the duration of the trip. Good excuse to get a new knife.
BTW, one way to ship ahead is to buy a new knife (see how I did that? always looking for some way to "need" a new knife. ) and have it shipped directly from the on-line dealer to the hotel.
Finally, I always carry a USPS flat rate box, pre-labeled and ready to go to throw the knife in and ship home. The hotel will always handle getting it into the mail for you.
Best of luck and enjoy your trip!
6 Manix 2 [blk/blk S30V, blk/blk XL, blue Sprint, blue LW, S110V LW, S90V CF XL]; 2 Delicas [VG10, Super Blue]; 4 Dragonflies [Tatoo, VG10, ZDP-189/Nishijin, Super Blue]; 4 Natives [S30V, Brn CTS-XHP, G10 S35N, Forum S110V]; 2 Chaparrals [Stepped Ti, CF]; 3 PM2s [blk/blk, blk/red Putnam, GRN CTS-204P sprint]; 1 CF bolt-action Sage; 1 Air; 1 Super Blue Manbug; 1 blk H1/blk frn Pacific Salt; 2 Stretch [Super Blue, ZDP-189]; 2 Enduras [VG10, blue jigged bone Damascus]
Native, Manix 2 (BD1,154CM,S30V,M4,XHP,S110V,Cruwear), Delica 4 (White,Red,Brown,Blue,BRG,G-10), Spyderhawk, D'fly (H1,G-10,SB), Police3, Volpe, Military (S30V,XHP,D2,M390,BG42,440V,Cruwear), Superleafs, Forager, D2 Para, Kopas, Kiwis, Caly (JR's,3,3.5), Para2 (XHP,204P), Stretch (SS,FRN's,CF), Rescues, Dyad Jr, Pingos, Southard, AIR, Jess Horns, Forum N5, Lil Matriarch, Barong, Superhawk, Chinook II, ATR, SPY-DK, Captain, Ti UKPK, Mules