I'm not 100% sure what you're asking here. Are you looking for a way to bring your PC with you on your flight, or are you looking for the best way to pack each of the components, but you don't have the proper packaging for the mobo and cpu? Assuming you are speaking of the latter, put the cpu in its socket on the motherboard. Put all of that in an anti-static bag. I would recommend taking it on the plane as a carry-on so you can assure it is being properly handled. Therefore, find a shoebox or something similar and line it with 2-3 layers of anti-static bubblewrap. Fill the box about 1/3 of the way with packing peanuts or newspaper, place the motherboard inside and fill the box the rest of the way, making sure it can still completely close. Use duct tape to wrap the box and make sure it will not open during travel. Put this in your carry on. You may want to wrap the exterior of the box in bubble wrap as well. Do your best to make sure the box is packed fairly tightly in the carry on, to prevent it from shifting around too much. Some of the wrapping may seem excessive or redundant, but better safe than sorry. Also, anyone else should feel free to correct me on this or improve my method. Best of luck.