In June, I flew to California from Michigan to do altering of uniforms for the Blue Devils (World Champions!!) Drum & Bugle Corp that my son was marching with. I put my machine, Janome 4000, in a carry-on suitcase. I padded it with towels and it went right up in the overhead compartment. I did need a little help in lifting it but had no problem getting it (the help). Interestingly, it was not the airline personnel but other travelers that were most willing to help. I did let them know when I went through the scanner that I had a sewing machine. If you wanted more padding, you could use bubble wrap or put heavy cardboard on each side. My concern was the weight; it could not weigh over 40 lbs. I flew NW (Delta). Good luck. I know what it's like to not have YOUR machine. I spent 2 weeks on a horrible machine when helping with another drum corps and vowed never to do it again. It was worth it to have my own that I knew the ins and outs of.
Wendy