Potential Estimation of Load Alleviation and Future Technologies in Reducing Aircraft Structural Mass

Abstract

In recent years, load alleviation technologies have been more widely used in transport aircraft. For aircraft already in service, load alleviation can contribute in extending the fatigue life, or enable small configurational changes. If load alleviation is considered in the aircraft design process, the structural mass of the aircraft can be reduced. This paper investigates various maneuver and gust load alleviation algorithms as well as potential future technologies regarding flight operation, turbulence forecast and material science, and it evaluates the mass reduction that can be achieved. In doing so, a long-range transport aircraft was taken as the reference, and the considered load case conditions were 1-cos gusts, maneuvers and quasi-steady landing. Based upon the loads, the composite structure of the lifting surfaces was optimized, while the secondary masses as well as the wing planform were kept unchanged. With all technologies implemented, a reduction of the wing box mass by 26.5% or 4.4% of the operating empty mass could be achieved.

Investigations on the Potentials of Novel Technologies for Aircraft Fuel Burn Reduction through Aerostructural Optimisation

“…Hence, the research is also characterised by lower values from the limit load factor of 2.5 obtained by using CS 25.337 [20]. The use of lower maximum-load factors as a way to take into account the effect of the technology in reducing weights during the optimisation is justified considering different research studies performed by using these assumptions to model the load-alleviation effect (such as [22,23]). Moreover, these values assume that load alleviation can counter gust and manoeuvre loads by a minimum of 20%, while flight safety in case of system failure is assured by using safety factors that are typically used for conventional aircraft [24].…”

Development of an Active Wingtip for Aeroelastic Control

“…Maneuvers, such as high-speed turns and aggressive flight maneuvers, impose significant loads on the aircraft structure, which can lead to increased weight and reduced efficiency. Active control systems can actively counteract these maneuver-induced loads, mitigating their impact on the structure and allowing for lighter and more efficient designs [10,11]. The implementation of advanced control algorithms and actuators enables active control systems to dynamically adjust the aircraft's control surfaces and redistribute loads during maneuvers, effectively reducing structural stresses and improving overall performance [12][13][14][15].…”