Average time to solo a student

On Sunday, June 3, 2018 at 11:43:58 PM UTC-4, wrote:

I soloed a new student this weekend. He flew three solo flights & did a spectacular job. He has no former flying experience so he wasn't the typical add-on pilot that I'm usually teaching.

On line it appears in several places that the average time to solo a glider is around 40 flights. Is they information accurate? My student doesn't have nearly that many flights.

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Well, as usual, "it depends" - particularly on age and frequency of flying. In my 40 years of instructing in gliders, I find the SSA's estimate of age plus 25 for ab initio students to solo pretty accurate. But I've seen as few as 20 or so for teenagers, and one that required over 90! For add-ons, it's all over the place depending on, e.g., not only age (older takes more sorties) or if they have any tail-dragger time (which shortens the number of sorties needed to solo).