I am skeptical, however, of the notion that flying a particularly aircraft type at one time in your life will thereafter make one a pilot better at flying other aircraft types. Piloting skills evaporate quickly if not used routinely … so that process of “once upon a time” earning a glider rating (or a tailwheel endorsement, or a seaplane rating) produces an effect that quickly evaporates unless it’s used routinely in the aircraft one actually flies. Breezy generalizations about the superiority of glider flying skills aren’t very useful either, though we see them repeated over and over again in aviation pubs and comment pages.
Holders of a valid FAA Power plane license with 40 hours as pilot-in-command need a minimum of 10 solo flights to qualify to take the glider flight test. No written exam is required to add a glider rating to a power license. In all cases, refer to the Federal Aviation Regulations for details on pilot licensing.
I obtained my SEL license in a taildragger I had bought, then took aerobatic lessons and then got a glider rating and bought a competition sailplane, all in about a year. Why?
At the risk of (inaccurately) coming across as aviationally elitist, I’m most comfortable sharing a cockpit with pilots also having at least a few cross-country sailplane flights and off-airport landings under their belts. Why? Fundamental piloting skills, general weather awareness, mental outlook and approach to routine in-flight considerations. I don’t mean to suggest the absence of a few self-inflicted off-airport sailplane landings precludes a person from being a fundamentally skilled, aware, and eminently safe power pilot, of course. Far from it. It’s just that even the relatively simple act of “collecting a glider rating” can easily have beneficial blow-back; learning how to soar without ever leaving the vicinity of your training airport even more; planting a foot in both the power and soaring worlds still more.