I was going to suggest this, as it is used in virtually all forms of motorsports as the baseline. Still not fair to electrics, however. The new technology is just different and doesn't fit the same framework we are used to. As pointed out, though, it is currently possible to make the limit with electrics. But at significant expense. But then, what doesn't cost $$$ in any form of competition that involves equipment and technology?

Here is a question that I have never heard the answer to - what was the purpose to the 5kg limit in the first place? Since the engine displacement limits were removed, it seems to me that eliminating the weight restriction and simply limiting the envelope dimensions to dictate model size would make the most sense. It might make a 2M plane more affordable by allowing people to build slightly heavier aircraft that still fly well But past history in pretty much any form of competition says that this generally doesn't work as intended. I am not trying to get people going about previous battles relating to the weight/engine/cost issues, just wondering what the intent of the original 5kg limit was?

Mark