[Guest]

It may happen that you rename all your .dat files to _ru.dat in DGen folder and get your dynamic campaigns back in English but the game interface itself is still in Russian and you can't figure out how to fix that.

Installing this modification will get you a nice alternative (old style IL2) interface AND in English!

[ROSOBORONEXPORTCORP]

It doesn't fix single player linear campaings...

[Guest]

It doiesn't fix _any_ campaign briefings.

This is to fix the interface itself in case the whole game turns Russian after installing the sound mod. That happened to me and I've read posts from at least another couple of guys after that.

For Dgen, there's the .dat file trick but for linear campaigns I've never seen this problem. I can only guess thet the static campaigns that came with the game have _ru.properties files besides refular .properties files: deleting _ru.properties files or replacing them with files written in English should fix that.
If the program doen't find any _ru.dpoperties file in the folder, it will read regular .properties files, I know because my downloaded static campaigns work normally with no language problems.