Post by Yellow Sun
The CAA may have strong suspicions that unlawful activity is going on, but mounting an investigation that might stand any realistic chance of gaining the evidence to justify a charge, let alone proceed to prosecution would be eye wateringly expensive.
Some 10 + years ago, a CAA Flight Ops Inspector commented to me "we know these things go on but as we're not allowed to question the culprits with a cattle prod behind the hangar, it's hard to catch them!". I doubt much has changed.