There's no such thing as free energy though. "Less resistance" is not "no resistance", there's still drag on that 2nd plane and it's going to cost the 1st plane

There's no such thing as free energy though. "Less resistance" is not "no resistance", there's still drag on that 2nd plane and it's going to cost the 1st plane more energy to pull it. I think the extra energy to pull a 2nd plane would be greater than putting a longer body on the 1st plane because the air wouldn't need to flow over another nose and set of wings.