Moving across country-Kitty travel

Not sure if this is the proper forum for this, but here it goes: I moved to Boise, Idaho a year ago as part of a federal program AmeriCorps VISTA (great program look it up!). The program places people with organizations trying to eradicate poverty, for a year. So I decided it would be yo much of a hassle trying to bring my cat, Flea. And my brother graciously accepted to take care of him. However the good news is that I got hired full time by the nonprofit I was placed with. I was wondering how to bring my cat back, my brother is located in Washington DC. And unfortunately the flight I bought is a 8 hour flight (Boise has a crappy airport) that fortunately allows pets on the air travel. Question is do I need to get anything special for this travel? Clean bill of health? Something to sedate the cat for only the duration of the flight? How to make flight as comfortable for all parties involved?

You will need to check with the airlines for their guidelines on traveling with a cat.  You then can speak with your vet and see if it is possible to get a sedative.  There are certain carriers that are required by the airlines. 

Each airline has its own requirements.  Generally if your cat is flying cargo you need a Health Certificate from a vet within 10 days of travel.  I don't know if you do for carry-on cats.

If kitty is going cargo, I strongly recommend against sedation.  There have not been, in my opinion, sufficient studies about the way sedatives are metabolized at high altitudes, and if something goes wrong, no one is there to see.  If kitty is flying in the cabin under the seat in front of you--I have traveled this way with chinchillas--then at least you are there to observe if something is going wrong.  However, there are also isn't much you can do in a plane as far as first aid.

I much prefer to drive whenever possible.  Yes, it takes longer, but it's less stressful in my opinion.  I drove from Portland, OR to the Chicago area about 6-7 years ago with two dogs and four cats.  Because of the size of the vehicle, the cats were two to a medium sized dog crate with litter box access.  It was a tight squeeze but everyone was much happier.