Flap 5,
"they [engineers] dont tend to come on airtests !"
I find that hard to swallow, every company I worked for, if an airtest is required for engineering reasons, the engineer flies in it.
"one of the best ways to ensure a helicopter is fixed properly is to have the engineer who did it onboard with you afterwards"
Pilots do not tell engineers what to do.
Most engineers I know (including me) fly in every aircraft we fix out of professionalism & faith in our work.
Your comments are insulting.