Whenever there’s a requirement for special help or disability assistance while flying with Aer Lingus

Here on this page by Air1Network is elaborated on the steps to add wheelchair assistance to your KLM Airlines booking.

If you require wheelchair assistance when traveling on British Airways, you can request this service at the time of booking or up to 48 hours before your flight departure.

If you require wheelchair assistance when traveling with Air Canada, you can make a request for this service.

Some passengers who are differently abled or have an injury may request a wheelchair service while boarding in the cabin. Delta Airlines is one of the comprehensive flights that cater to all types of unique needs.

If you need special assistance, it's recommended that you make arrangements in advance by contacting American Airlines at 1-800-433-7300. 

There are two methods available to you if you need to ask United Airlines for a wheelchair immediately in such circumstances.