Airplane trip with turntable...

With a situation like this, you never know what's going to happen. The TSA people are not the brightest. Get the right agent, and I can see you ending up on the 6:00 news. Any time I have to deal with any type of official, government or otherwise, I always assume the answer will be no, and expect the worst. At least with FedEx or UPS, you have a chance of getting the box there without any problems.

Thanks for thoughts.
I will fly US-US...
The turntable itself isn't big even with packaging.
I will simply feel safer about it if it's underneath the seat rather than shipping it.
I want to void driving 800 mi as well.

Beware, they are going to make you unpack it in the airport, especially if it's in an unmarked box. Take packing tape with you to repack it with on the spot.

I carried a McIntosh MC-225 tube amp on a flight one time from Atlanta to Philadelphia in 2008 or so. It was in a "custom" cardboard box with a lot of duct tape all over it. Very shady looking, but I had to go with what I had on hand at the time. My friend thought I was going to get a full body cavity search, but I decided to risk it anyway because I was already checking a C-20 preamp and didn't want to check this as I had no way to safely pack it for that. You want to know what happened? Absolutely nothing. They didn't even ask me what the hell it was and they sure didn't ask me to open it.

Another time, also from ATL to PHL, I carried on an Eminent Technology ET-2 tonearm. This time they made me open the box. They were not happy at all. Upon sending it through the X-ray machine:

"What's is it?" they said.

"A tonearm for a turntable," I said.

"Remove the instrument," demanded security (they were not happy!).

I slowly opened the box to reveal the arm. I don't think I even took it out. I guess they realized how delicate it was by the way I opened the box and decided that it could never be used as a weapon, I don't know. He certainly did not think, "Oh, yep, that's an ET-2 alright."

"Proceed," they said.

I was sweating bullets!

A turntable with a conventional arm is a little more recognizable, so I think you will be OK as you're sure it will fit in the overhead compartment or under your seat. The dimensions of these compartments are easy to find if you do a quick search online.

I recently carried on a turntable on a flight to the CES Show. A good thing i had a record with me because TSA wanted to see if it was really a turntable. I put on Al Coltrane and to my surprise the TSA agent had seen him live and really loved the music. Needless to say I made it through OK.

Good luck with your trip.