Folding Wing Tip Assembly With Spar Extension Load Transfer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The challenge of providing a practical folding arrangement for aircraft wing tip devices that accommodates large wing spans while ensuring reliable hinge mechanisms and lightweight drive systems, particularly in aircraft with increasing wing aspect ratios and decreasing wing box thicknesses, is addressed.
Innovation Solution
A wing assembly design incorporating a spar extension that transmits flight loads between the wing tip device and the inboard wing, allowing the wing tip device to move between flight and ground configurations, with a spar extension disposed within the wing tip device to reduce the need for bulky components and facilitate efficient load transmission.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If wing aspect ratios are increased to improve aerodynamic efficiency, then flight performance is improved, but wing box thickness must be decreased which limits the space available for folding mechanisms
Solution Approach 1:
The spar extension protrudes from the wing box in a direction transverse to the spanwise axis, utilizing the chordwise dimension rather than increasing spanwise thickness. This allows the folding mechanism to be accommodated within the existing wing box volume while maintaining high aspect ratio and aerodynamic efficiency.
Solution Approach 2:
The wing structure is divided into the main wing body and a separate spar extension that can move independently. The spar extension is detachably connected to the wing, allowing it to be folded away from the main wing during ground operations while maintaining the full span during flight.
2Length of moving object
If wing tip devices are made larger to increase span, then flight performance is improved, but the weight and size of actuation assemblies must be reduced
Solution Approach 1:
The spar extension is extracted as a separate movable component from the main wing structure. By detaching the spar extension from the wing tip device, the actuation assembly only needs to move the lightweight spar extension rather than the entire wing tip device, significantly reducing the required actuation power and weight.
Solution Approach 2:
The spar extension is designed to be movable between a stowed position (transverse to the spanwise axis) and a deployed position (extending the wing span). This dynamic configuration allows the wing span to be increased during flight while minimizing the weight of components required for ground operations.
3Adaptability or versatility
If folding arrangements are added to reduce span on ground, then airport maneuverability is improved, but reliable hinge mechanisms must be provided without impacting wing design
Solution Approach 1:
The spar extension acts as an intermediary component between the wing and the wing tip device. It provides a dedicated mounting structure for the hinge mechanism, isolating the folding arrangement from the main wing structure and allowing reliable hinge design without compromising the wing's structural integrity.
Solution Approach 2:
The spar extension is pre-configured with mounting structures and attachment points that are prepared in advance for the hinge mechanism. This preliminary preparation ensures that the folding arrangement can be reliably integrated into the wing design without requiring modifications to the main wing structure.
Data Source
AI summary
A wing assembly for an aircraft is disclosed including a wing and a wing tip device at the tip of the wing, wherein the wing tip device is moveable between a flight configuration and a ground configuration. The wing has a spar extension which extends spanwise away from a distal end of the wing, the spar extension having a first end portion fixed in the wing and a second end portion which, in the flight configuration, is positioned in the wing tip device such that, in the flight configuration, the spar extension transmits flight loads between the wing tip device and flight-load bearing structure in the wing. The wing assembly may have an actuation assembly to move the wing tip device.