Ok guys and Gals I run a training school with 300's Here's my input.
To 1st solo depends upon
a. have you done fixed wing
b. age - how quickly you can pick things up
c. how often you fly
d. the type of helicopter you fly
Personally all my students will have done lesson 13.14 and 16 before solo ( sideways, backwards, eol's) before going solo
The best I have had is 7 hours ( fixed wing instructor ) the worst 24 hours ( 64 years old taking one lesson a fortnight )
The average appears to be 15.3 hours
A question about 20 hours in an R22, having insured machines for nearly 15 years i have never seen any clause about time to 1 st solo, me thinks it is a good way of skinning the student.