Ah yes. So what happened was on the J-20 thread, we were wondering how much RAM weighs and I also thought it would be negligible since it's just skin. Then, someone, I think Santos, came and said that the average surface area to cover for a heavy fighter is 200m^2. Then he said that the paint is metallic; you cannot absorb radar waves with Home Depot paint LOL. So assuming a 3mm thick skin with 200m^2 surface area, that is 0.6m^3 of metallic material. Calculating with density of iron at 7.9 tonnes per m^3, that makes the RAM 5 tonnes. That's very very heavy so we were thinking it would be significantly less than that since RAM isn't just pure iron. But also, we didn't check sources for the claim of 200m^2 average surface area of heavy fighter, we didn't check sources for 3mm thick skin and we of course don't know the actual weight of the material. So a LOT of things could be wrong with our assumptions but it gave every member participating the idea that RAM could weigh a few tons. I'm very much open if we get any real evidence that it weighs less (or more).