Interesting thread on the Tesla forum towing an Airstream.

Terryallan wrote:
I missed where it said what the range is, and how long it takes to recharge. Read it a couple times, and can't find it. Would be good to know

At 660Wh/mi the top end model X would have a range of ~120 miles, recharge rate is ~80 percent in 40 minutes (75 minutes for 100 percent, it slows down considerably at the end as you risk damage and possibly fire by pushing them to hard at the end). I do have to say the idea of splitting a 50A circuit between the car and trailer is great.