My friend has broken her ankle and can't put her foot on the ground for 4 weeks, resulting in us hiring a wheelchair to get her around. I find it very awkward to get her out of the vehicle and into the wheelchair and vice versa in public carparks. In this situation, am I allowed to use disabled parking although I have no disabled badge?
no, you have to actually display the blue badge to park in these spaces. contact your local Social Services to find out if your friend can apply for a temporary badge.
There is nothing to stop you parking in a very convenient place such as double yellow lines and getting her in to the wheelchair and then straight away parking in a proper place.
The law states that you can stop on yellow lines to drop off and pick up passengers - the restriction is 'no waiting'.
Make sure you don't park on a clearway though - that is not allowed.