there be no type ratings below 12000lbs in US.
That is quite correct.
The statement was that One could jump into any helicopter and fly it. The statement holds (somewhat) until you get to Commercial Ops under Part 135 then you have Minimum Training Hours and Syllabus and a Check Ride before you can fly for hire.
The Accident occurred on a a Commercial Part 135 Flight thus training both ground and flight required prior to the Check Ride.
http://flightsimaviation.com/data/FA...t_135-244.html