An erroneous conclusion is that tri-jets cost more to operate than competitive twin-jets. This is not true.
Long-range, twin-jets use excessively large engines and supporting structure to support them. Tri-jets with their efficient configuration, utilize smaller more fuel efficient engines.
With fuel-efficient engines, the tri-jets carry less fuel than twin-jets. This results in a reduction of weight and operating costs. Smaller engines and the tri-jets aerodynamic improvements, and lower operating weight culminate in an aircraft that burns significantly less fuel than a heavier twin-jet.
In this time of unrelenting fuel-price increases, tri-jets owners and operators enjoy lower fuel costs.