What jack to have onboard for roadside tire changes?

Thanks for the help. The HR does have levelers, and I always have the cellphone, road service and credit card. I guess I'll just keep the bottle jack and hope that things work out if the time ever comes!

Do you believe that you alone could change a tire of that size?

I had a flat several years ago on the inner dual - before I learned RV tires age out after 7 years.
My MH didn't have levelers.
I called my road service and about 2 hours later Homer and Jethro showed with in a broken down El Camino with their huge floorjack and crossbar wrench. Unfortunately, after they pushed it under my MH, the restricted movement on the handle didn't allow the pump to function so they couldn't use it. I offered my bottle jack which they were able to get under the axle and raise the tire off the ground. They were able to swap tires but as they were tightening the lugs, they put enough torque on the lugnuts to turn the tire causing the tire on the opposite side to turn the other way and the HM came down hard off the jack. They (and I) had forgotten to chock the tires! Lesson learned and disaster was avoided.

If you blow a tire and the wheel digs into the ground, I doubt if you'll be to get anything to raise the wheel at that location because anything you use will just push itself into the ground while trying to push up on the axle. Best to call your roadside assistance provider and let them handle it - hoping Homer and Jethro aren't the ones they send.

You could also drive the flat tire up onto a 2x6 board or two in order to lift the axle a bit before setting up the jack

a working, charged cellphone, a roadside service plan and a credit card.

Does your HR have hydraulic levelers? I've used them to raise an axle high enough to get a 20-ton bottle jack under it on occasion.

Actually, if you have a leveling system on your coach, use that. I normally do not recommend ever raising the real wheels off the ground, but I do know that it can be done. during the one rear tire blowout we have had, I called my emergence road service to come change it for me. I asked the service person "my jacks or yours", we used mine, then he put a jackstand under the axle for safety, and we lowered onto it. With a dual axle, I don't know. He said that he actually felt better about my jacks than his!