You can ask for on-board wheelchair assistance. If you need a wheelchair right from the time you check-in till the time you board, that is also possible. 

You should inform Alaska of your need when making the reservation, either online or by phone. The customer service agent will be able to take a wheelchair request on Alaska Airlines. 

Wheelchair assistance when flying with Spirit Airlines will not require you to fill up a lengthy form. It is simple and convenient. The airline allows passengers to add this service in several ways. Spirit Airlines wheelchair assistance is free of charge. 

Need wheelchair assistance at the airport with Frontier Airlines? It is easy to arrange & gives you a smooth start to your flying experience. Just book the service during your flight reservation or notify Frontier representatives at the airport for immediate support. 

If you require wheelchair assistance, they ensure a seamless and hassle-free travel experience.

Virgin Atlantic is committed to providing exceptional service and ensuring a comfortable travel experience for all passengers.

Turkish Airlines, one of the leading airlines in the world, prioritizes providing excellent service to all its passengers

The airline also offers priority boarding, dedicated check-in counters, and pre-boarding assistance for passengers with reduced mobility. 

EasyJet is a low-cost airline that provides wheelchair assistance to passengers with disabilities or reduced mobility.

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.