A 1 lb saving saves $2,600 in fuel costs over the life of the craft.
However, an airline's break even point is a portion of that (perhaps $1,000) because the fuel costs are spread out over the life of the craft and there is an opportunity cost to spending money on the more efficient plane.
Of that $1,000, the aircraft maker will only capture a portion of the value - the airline expects to do better than break even. The airplane manufacturer may be able to charge $500 more for the aircraft.
They might hope to make 2,000 aircraft for something big like a 787 (although that number varies a lot depending on the model). That's 2,000 units times $500 = $1 million.
However, an airline's break even point is a portion of that (perhaps $1,000) because the fuel costs are spread out over the life of the craft and there is an opportunity cost to spending money on the more efficient plane.
Of that $1,000, the aircraft maker will only capture a portion of the value - the airline expects to do better than break even. The airplane manufacturer may be able to charge $500 more for the aircraft.
They might hope to make 2,000 aircraft for something big like a 787 (although that number varies a lot depending on the model). That's 2,000 units times $500 = $1 million.