July 7, 2023, ©. Leeham News: We explore different technologies in the series that can make our next-generation airliners more efficient and, thus, less polluting.
We have discussed developments of engine and airframe technologies, such as Turbofans versus Open Rotors and different airframe configurations to minimize drag and, thus, energy consumption.
When utilizing these developments to increase efficiency we must fly the aircraft in a different way depending on the technology.
And how we fly the aircraft is not only influenced by the factors we have discussed. We must consider factors at the airplane level, at the airliner operational level, and finally, at the airline fleet level.
We have discussed factors influencing airframe and engine efficiencies like optimal fuselage forms (single aisle vs. dual aisle, Figure 1), low drag airframe trends (lower parasitic and/or induced drag, Figures 2 and 3), and engine advances.
These are all aircraft technologies to lower the energy/fuel consumption of the airliner and, by it, emissions.
But airplane operational cost minimization involves more than minimizing energy/fuel consumption. The optimal cruise speed for the airframe is not optimal speed for an aircraft with crew and passengers. Time-dependent cost factors now modify how the airliner shall be flown.
Seen at an even higher level, a flight profile that minimizes operational costs might not be the profile that optimizes the airline’s fleet utilization.
We will discuss all these different aspects and how the new technologies affect energy and cost optimizations at different levels.
We start by looking at what consequences different airframe/engine changes have for how the airliner shall fly. Example:
Then we look at what this means on the next level of optimizations:
We start by looking at airframe and engine-related factors next week.