On average between 15-20 hours. When I began instructing in the mid
60's the emphasis was on getting a student soloed under 10 hours. But,
it was and is my opinion that when that student goes up for the first
time, they better be ready to handle oddball things that come up on a
regular basis.
When I first start with them, I tell them solo is just one step in the
route to a private license and there should be no major rush. When I
step out of the aircraft, I am comfortable that the student can go to
the practice area and do every maneuver required on the private check
ride and do so safely.
I recently finished a student who never flew with anyone else. He
soloed at about 17 hours and got his private check ride out of the way
at 41.5 hours. Now he has gone to another operator to start on his
instrument rating as I left the area.
Ol Shy & Bashful CFI/AIRM-Gold Seal 1968