There are two types of radio currently in use by UK paraglider / hang glider pilots; those on the "air band" AM frequencies and those on the VHF FM 2 metre (amateur) band frequencies.
The use of 2m radios from the air is currently illegal, although the BHPA Airspace Panel is working hard to change this situation. This may take some time as discussions are held at both a Governmental and EC level.

VHF FM 2 metre band.
Most UK and European pilots use 2m radios and the sets are readily available, reliable, efficient and cheap - most pilots will broadband their 2m sets and operate just below the Amateur band.
Why? Because using an FM set gives much better clarity and range than Airband on AM, and the broadbanded frequencies used are free from other radio chatter.
Some 2 metre sets (when broadbanded) will receive airband AM transmissions to allow Volmet weather reports to be monitored. None will transmit on airband.

Airband AM
Very few UK hang glider and paraglider pilots choose to operate on airband even though there is now a dedicated frequency on air band for foot launched gliding, in addition to the 5 dedicated gliding channels to which we also have access. Airband sets may be useful for UK paramotor pilots who do have access to many local airfields if equipped with a radio and RT licence, and indeed any pilot not wishing to break the law. When operating an airband radio on any of the glider channels a full RT licence is NOT required, as long as the radio frequency cannot be changed off of the dedicated channels when in flight.
When using an airband radio, a licence is technically required for the radio itself. This is available from the CAA for a nominal fee.