|The international requirements do permit passengers to carry small oxygen or air cylinders for medical use, but only with the prior agreement of the airline. Some airlines do allow passengers to carry their own cylinders or will supply (usually for a fee) special cylinders for passengers, whilst other operators do not. Additionally, where an airline does agree to carry a cylinder, there is no definition of the term "small", but our guidance is that the cylinder must be small enough to fit under the passenger's seat (if the cylinder is being used during the flight) or the overhead bin.|
The British Lung Foundation provides advice and tips about flying, including travelling by plane with oxygen, and includes the contact details of a number of UK airports. British Lung Foundation
We would advise to check with the airline prior to buying the ticket, and where airlines agree to carry the cylinder, that agreement is obtained in writing to avoid any confusion when checking in for the flight.