They’ve never asked me and have made 3 flights to The Canaries with them in the past. There’s nothing I could find in the Jet2 Hazardous Items web page about needing permission. Just that they ask you to ensure you meet IATA/CAA rules regarding capacity and terminals etc.
Not so useful for you with a QRO radio but when using just 5W CW I’ve used 18650 cells in a USB power pack. Looks like and works as a USB power pack which the security guys see all the time. Remove the cells and put them in a 3x 18650 cell holder to power the radio when you get to the destination. (See Autumn Activations in Southern France, Mont Bouquet, there’s pictures of the setup used near the start of the thread.)
If you hadn’t found it there is a specific category of Transport Security with loads of posts about airport security etc.
https://reflector.sota.org.uk/t/airport-security
https://reflector.sota.org.uk/t/airport-security-part-2
Lot’s of useful info Simon. It’s a few years since I was in Lanzarote and I’ll be back sometime in 2022 so new summit routes are welcome.