Free flight models - by their very nature - require large areas of accessible land for successful flying and retrieval. Of recent years many such flying sites have been lost or made infrequently available. The BMFA organises competitions for freeflight and arranges venues ( normally M.O.D. sites ). However , for those not so competitively minded , it is becoming necessary to look for local flying sites. These are normally relatively small and so the types of F/F models being flown tend to be smaller and less geared towards maximum flight times. Some owners are now installing RC - not to control the whole flight but just to assist in keeping the model within the bounds of the site.  De-thermalisers are also fitted to bring the model down after a preset time.Most engine powered models also have restricted motor run times to prevent fly-a-ways.