Captains are compared a lot but to be honest I think after the captains, skipping over the XO or security men etc. the engine room head honcho is probably actually the most influential character after the captain, in each series. Just my personal opinion. I haven't seen this poll before. I always would have thought Scotty, but I have got kinda endeared to Trip and his impulsive redneckery. The guy looks and acts like someone who you would expect to see half under a car with tools scattered around. Ultimately probably still Scotty... though O'Brien gives him a good run for his money.