The skills learned as student pilots should last through an entire career, however many skills are perishable. They must be refreshed on a regular basis. The need for refreshing some skills such as instrument proficiency has been widely recognized in all of aviation for many years.
Most other skills have not been acknowledged as being perishable so it is important to note that any skill not practiced on a regular basis may be perishable over time. Some additional examples of perishable skills may include helicopter autorotations, use of advanced avionics, or flight into confined areas, soft field landings and night operations.
Recurrent or refresher training to be effective should include all the perishable skills that may be needed for the type of flight operation. Each training session should allow for the pilot to request practice and/or training in skills or maneuvers that might lose proficiency over time. There are many skills that fall into a “perishable skill” list especially when regular flight time does not meet certain conditions. The most obvious of these is flight in low visibility conditions. IFR and inadvertent flight into IMC are frequently addressed as an area of additional training. Other perishable skills are often overlooked.
Maneuvers and equipment not employed on a regular basis such as autorotations or night vision goggles should always be addressed in recurrent training. Normal training session in aircraft often avoid emergency procedures that are difficult to replicate in an aircraft without significant risk. This is an area where scenario based training in flight simulators is extremely effective. Most risk factors including visibility restriction and emergency procedures can be practiced to proficiency in simulators.