In all the helicopter exams I have sat, including the last one, I have had several fixed wing questions. I clearly remember the last exam I sat had a question regarding take off and landing seperation standards, they didn't even have the correct seperation distances for helicopters in the list of answers to choose from.
I am sure that some of the questions I have answered incorrectly in other helicopter exams have been marked using fixed wing answers.
I actually failed one exam by 2%. If all the exams that were failed because of this problem, I believe that ASL would go broke repaying the exam fee's and supervision fee's.
