I am late to answer this one, but can think of a number of reasons for this:
- Aviation and programming are both technical fields, so I would expect to see some crossover here. The same types of people tend to gravitate to both.
- Programming is generally a well-paying field, and there will be more people than average who have the means to become a pilot.
- Professional pilots generally have a fair amount of free time, both while working (sitting in hotels) and while not flying (sitting at home) in between trips. This gives them the time and resources to explore other interests, especially ones like programming which can be done from anywhere.
- They both require the mindset of "perpetual learning" since the fields are so large and complex that it's impossible for someone to know everything about it. Again, similar personality types are generally attracted to them both because of this.
Personally, I was a pilot / "free time programmer" and was active on SO before Aviation.SE was even proposed on Area 51. I was very excited to have a place with the same format as SO where aviation questions could be asked since it does involve so many technical aspects with well-defined Q&A's. I put a lot of time and energy into helping the site get up and going, and am very happy that it has turned out as well as it has.
Thank you all for making my early visions come true and making this a truly valuable resource for the aviation community as a whole!!