To be clear, I'm not talking about putting the gun from the Apache on the jetpack, just the helmet and a small arm (e.g., something with a caliber like a handgu

To be clear, I'm not talking about putting the gun from the Apache on the jetpack, just the helmet and a small arm (e.g., something with a caliber like a handgun). You could be right that that would weigh too much, but that's not at all clear to me.