My 1964 book is green as well. Certificate # 40166.
So about 11,500 A&B certs from March 1960 to some time in 1964, the vast majority of whom would be through the ATC VGS system
How many in the last 4 years ?
A high proportion of the RAFGSA and BGA glider pilots of my generation started with the ATC; many of the RAF personnel I served with in the '60s came by that route. What have we (the UK) lost?