I wear a navy blazer a lot. I would say that I have been wearing a navy blazer at least once a week for the last 3 years. I have learned a few things in that time. One of those things is that red ties work really well with them.
In hindsight it seems like this should be a no-brainer. Contrast is one of the most important elements in putting together a rig. However, my knowledge of color theory is non-existent so I learn what colors work by two methods. Learning from others is my most effective. There is no reason to reinvent the wheel. The other is trial and error which is why I recommend the first.
in the end, red ties just work with navy blazers. When I say red I also mean burgundy ( I told you that I have no background in color theory). These are the ties that I reach for most often. If you are new to the navy blazer or have trouble pairing a tie with them give a red or burgundy repp tie a shot. It is usually a hit.