Did my interview at the end of September. I have a DHC 8 PPC as well and no questions on the airplane. No tech questions during my interview. Interview was a "story-telling" type interview...tell me about a time this and that happened to you and what did you do about it plus all the usual questions like why do you want to work for Jazz, what do you know about Jazz, where do you see yourself in 5 years, etc. Pretty straight forward and relaxed atmosphere at the interview. My interview lasted about 45 minutes which was standard according to the panel but a friend of mine had his last only 30 minutes.
Don't sweat it. Good luck!