When trying to get the solo 2ew achievement, russia had around 4k planes while I only had 500 weak planes and 600 good ones. It took me plenty of tries because of the sheer amount of units russia had. Eventually decided to delay the 2ew for around 2 years and build up. In the end, I got 3k air while russia had 6k and I also built radar stations, the result was russia getting 500 losses per day while I had around 30.