...why would anyone want a helicopter that they can't take passengers in?
It's worse! As well as not taking passengers, a P to F aircraft means you can't fly over congested areas. Or fly at night. Or fly abroad (without permission from destination country). The
CAP 733 describes all there is to know about P to Fs, but in the main it's a way to allow home-builds, ex-military, vintage and gyro/microlight aircraft to get in the air when they wouldn't otherwise qualify for a C of A. Your jetbox will almost certainly have had a temporary P to F when it was new, in lieu of its C of A being issued.
So why do people buy them? They're
much cheaper. When the MOD auctioned off its Gazelles, I believe some were going for well under £120k (Shy will prolly know the exact number) - not bad for a well maintained, 5 seat (and very fast) turbine. Unfortunately however, the insurance companies don't like them and it's virtually impossible for new owners to get insurance - which has driven the prices for all Gazelles down. But that's another story...
TTB