How to transport a family member who is somewhat incontinent?

I should call the airline you plan to use and ask them what special arrangements can be made. You won't be their first pair of passengers who need assistance. I doubt if they'll even think you're much of a challenge.

On the ground, you and your wife can use any facility for people with disabilities, which as far as I am aware are all unisex and have a lot more room for manoeuvre.

You do not say in what way she is incontinent...bladder or bowels. If bladder, she could be catherterized with a leg bag. If it’s bowels, then that’s a different issue. It sounds like you are moving to a new home, is that what I’m reading? This is not a vacation right? If you could have a trained aid with you to assist and then fly them back that might help. Airplanes are so small I don’t see how you can assist an adult inside of one. But I’m sure the flight attendants have dealt with this before. If your wife is docile and not combative in behavior, then it might work. Select seats near the toilet facilities. You might check with your local Alzheimer chapter and see if there is someone there to talk this over with.

Would a train trip be possible? Very enjoyable; there are wide aisles, plus a large restroom. Reasonable prices too. You can sit at a table if that is easier.  The station can be noisy outside so I’d even suggest headphones with music for your wife.  Best wishes to you

actually a public place that does not provide a family/unisex bathroom violates American Disabilities Act for such reasons as you described. File a complaint against the stores.

It's tough on a plane. Especially on a domestic flight where the restroom is very small. On wide bodies, there will at least be one restroom that is fairly large.

As for driving, where I live there are family restrooms pretty much everywhere. These are large single use restrooms for people who need help in the restroom.

Hey! There's a website for that.

findfamilyrestroom.com/

It is a tough situation. I encountered it in small doses, when I had to transport my LO, who was incontinent for shorter trips. Later, when Memory Care staff transported her, they would take her into bathroom to change her when necessary. It's a HUGE challenge. I've seen huge mishaps that would be difficult to handle with only one person. Large messes that require lots of supplies and time to take care of.  Even if you go to places that have family restrooms, it's a lot to clean up wet and messy mishaps.  Plus, there's the clothes, seats, shoes, floors, that often get messed up as well. 

I would consider taking a third person to help assist. Perhaps a female who is trained. I'd also consider the big picture and not just the bathroom issue. Going on this trip could trigger behavior that you are not expecting. With dementia she may be frightened, confused, agitated and even act out in ways that are scary. Especially in closed in spaces with lots of strangers.

I realize that private travel by plane or travel trailer is expensive, but, if funds I allow, I'd explore it. Perhaps, someone around here, who's done it will chime in.

You have asked a very difficult question to answer given all of the barriers that you have listed. I have seen people respond to similar questions with a specific organization that transports people, but I don't remember who they are.

Also, transporting someone with alzheimer's / dementia would be a challenge, I would think.

Someone who knows how the answer this question should find it and I hope for your sake, soon.