I declared this one to be the "Malcolm Miller" and I had a 50 %-chance to be right. The STA-schooners are for sale and in the "TALL Ship news" they wrote it was their last race. So it's good to have a photo of them before it's too late.
Later Visitors of this site (Stephen D Worgan and Mark Finn) mailed me I was wrong. They wrote this was the "Winston Churchill" since "Malcolm Miller" had rectangular tops of the hatches - unlike this one. Also the K1 designation on the mizzen was for Winston Churchill. Alright, I give in, I wasn't sure anyway.

Sir Winston Churchill