Source for reliable information on transit rules at a specific airport?

Question

Two important factors in determining the complexity and viability of a connection are:

1. Are there airside connections between place A and place B?
2. Even if there are, do I still have to go through security?

That seems to vary a lot from airport to airport and sometimes even from terminal to terminal without any obvious rhyme or reason. For example on my most recent trip I had to go through security in Istanbul and London Heathrow but not in Washington or Vienna (despite all being airside connections). In Boston you can get airside from Terminal E to C but not to A or B.

This information seems to be very difficult and tedious to find. Most airport's websites don't provide it. Best I have come up with are random Google searches or plowing through different forums like this here. It's time consuming, not very reliable and the success rate isn't great either.

Question: What's the most reliable or easiest way to determine whether an airside connection is available and whether another security check is required?

Answer 1

To find out whether an airside transfer is available for the particular set of flights you need to know which gates they will use and in many cases gates are not allocated till shortly before the plane arrives, and in those cases where it is known well before it can be changed at short notice. And while airports try to keep flights in the same section of the airport so security measures and transfers will follow the same rules, it is not always possible.
I'd say it is impossible to make a site covering that search function.

The same goes for going through security between flights, maybe even stronger, as airports do not seem to hesitate to have people go through an extra security check if it allows them to use a certain gate which may otherwise be unavailable.

So my answer is a 'No, not possible' as there are too many variables and those can change on very short notice.