Hi Maureen ~
It sounds like you are planning for a wonderful birthday celebration for your Grandfather this summer. It is super nice of you to plan ahead for his needs. It will make your trip a lot smoother once your reach Disney World.
You are welcome to take his wheelchair on the bus. If you do not want to fold it, he can remain in the wheelchair while he is on the bus. There are ramps to assist Guests with getting on and off the buses who are traveling in wheelchairs or ECVs. The bus driver will assist in securing the wheelchair if your Grandfather wishes to remain in it during the ride. You know your Grandfather better than I do, but it may be easier for him to remain in the wheelchair during the ride. He won't have to step onto and off the bus and if he is in the wheelchair it is one less thing for you keep up with for the trip.
Guests may also remain in their wheelchairs on the Monorails and some larger watercraft. You can find more information on the
Services for Guests with Mobility Disabilities page on the Disney Website. Once there, scroll down to the bottom of the page for information regarding
Wheelchair and ECV Accessibility with Walt Disney World Transportation.
Please feel free to visit us with all of your planning questions. We will be hEAR for you up until you embark on your pixie dusted trail!
Wishing you minnie magical memories :-) Allison V.