I'm currently in my early days of learning about aviation, and have just started learning how to use a VFR chart. One thing that I have noticed is that the class D airspaces generally have frequencies to contact the controller for that airspace. Outside of CAS however, there is nothing. Do you just tune the FIS frequency? I understand that the airspace isn't really controlled, but can you still ask for Traffic Service etc?
You want CAP 774: UK Flight Information Services. That document lists the air traffic services provided to aircraft in class G in the UK.
The services listed are:
A Basic Service is an ATS provided for the purpose of giving advice and information useful for the safe and efficient conduct of flights. This may include weather information, changes of serviceability of facilities, conditions at aerodromes, general airspace activity information, and any other information likely to affect safety. The avoidance of other traffic is solely the pilot’s responsibility.
A Traffic Service is a surveillance based ATS, where in addition to the provisions of a Basic Service, the controller provides specific surveillance- derived traffic information to assist the pilot in avoiding other traffic. Controllers may provide headings and/or levels for the purposes of positioning and/or sequencing; however, the controller is not required to achieve deconfliction minima, and the pilot remains responsible for collision avoidance.
A Deconfliction Service is a surveillance based ATS where, in addition to the provisions of a Basic Service, the controller provides specific surveillance- derived traffic information and issues headings and/or levels aimed at achieving planned deconfliction minima, or for positioning and/ or sequencing. However, the avoidance of other traffic is ultimately the pilot’s responsibility.
A Procedural Service is an ATS where, in addition to the provisions of a Basic Service, the controller provides restrictions, instructions, and approach clearances, which if complied with, shall achieve deconfliction minima against other aircraft participating in the Procedural Service. Neither traffic information nor deconfliction advice can be passed with respect to unknown traffic
These aren't always available and you don't have to use them. A Basic Service will let an ATS provider know you are there & I've had warnings about unusual activity (police helos, helimeds or fast jets letting down in class G) but I pretty much expect to be ignored. Traffic services are great but are often withdrawn at busy times (when you most need them) due to controller overload!
Even if I'm not recieving a service, I'll usually listen in to the local frequencies just for situational awareness. Also, if you're passing close to an ATZ, it's good practice to let them know where you are and where you're going.
Class G is uncontrolled free airspace. You don’t have to talk to anyone if you don’t want to.
If there is a nearby radar facility then you could call them and ask for a service if you like but it’s not mandatory.
In my opinion the ability to just go flying without talking to anyone or filing anything is one of the advantages of the way UK airspace is organised.