I remove anything that can be taken off DDs wheelchair and carry it on with me. Some of the baggage handlers have commented that I am bringing on half a wheelchair!
We have been doing this for a long time and no one bats an eye. Her current wheelchair does not have removable footrests, but when her wheelchair did, I removed it and carried it on.
Pieces I remove on her current wheelchair include:
headrest
armrests
seat cushion (she has a $700 specialized seat cushion with a gel pack)
seatback (custom seatback- also expensive with some protruding fragile pieces)
I carry a laundry bag in one of my carry on bags so I have a bag to throw all the pieces into and dont have to worry about dropping anything. The bag is nylon and compacts to a very small size to go back into my carry on bag.
I am not certain about the question about medical bag - you mean when you are leaving, you want to check that bag right away when you check in at the resort?
We have not checked a medical bag ever, so I cant answer. We sometimes fly an airline that is not supported for checking bags in at the resort. So, there have been times when we have had to bring our bags on the DME bus going back to the airport. Thats not been a problem; we store the bags with Bell Services from the time we leave our room until we are waiting for the bus. The driver helps us to get them on and off and then, at the airport, they do have Skycaps who can help.
If you are asking whether you can check the footrests at the time you check your bags, I would not do that. I would just remove them when you gate check the wheelchair.
Also, airlines are required to allow any medical equipment that will/may be needed during the flight to be carried on without charge. And, they are also required to carry mobility equipment at no charge.
There is not a requirement for them to carry a checked bag of medical equipment at no charge, although they all do(as far as I know). That bag can only contain medical equipment and supplies. If anything else is included, they can count it as a regular bag and charge whatever fee they would for a bag of that size and weight.