Aircraft Nacelle Thrust Reverser Access Without Opening Fan Cowls
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing aircraft propulsion systems require frequent opening of side fan cowls to access thrust reverser halves, leading to increased weight, complexity, and cost due to the need for robust cowl structures to withstand wind loading and gravity.
Innovation Solution
A nacelle design that allows the thrust reverser sections to pivot or translate independently of the fan cowls, enabling access without opening the fan cowls, reducing the need for robust cowl structures and simplifying the opening mechanism.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the first side fan cowl and second side fan cowl are configured to open frequently to access thrust reverser halves, then access to thrust reverser halves is enabled, but the weight, complexity and cost of the fan cowls increases
Solution Approach 1:
The nacelle is divided into functionally independent sections: the fan cowls remain closed and stationary, while the thrust reverser halves can be independently opened. This segmentation allows each component to perform its specific function without requiring the other to move, eliminating the need for complex opening mechanisms in the fan cowls.
Solution Approach 2:
The opening mechanism is extracted from the fan cowl structure and relocated to the thrust reverser half structure. The thrust reverser half includes its own attachment configuration that enables it to be opened independently, removing the burden of providing opening mechanisms from the fan cowls.
2Strength
If the first side fan cowl and second side fan cowl are configured with robust structures to resist wind loading and gravity when opened, then the cowls can remain open during aircraft operation, but the weight and cost of the cowls increases
Solution Approach 1:
The requirement for robust opening and holding mechanisms is extracted from the fan cowl design. Since the fan cowls remain closed, they only need to withstand normal operational loads, not the additional stresses of being opened and held against wind loading and gravity.
3Ease of operation
If the first side fan cowl and second side fan cowl are configured with opening systems and maintenance devices, then the cowls can be opened for thrust reverser access, but the complexity and cost of the nacelle increases
Solution Approach 1:
The nacelle systems are segmented into independent functional units. The thrust reverser halves have their own dedicated opening and maintenance mechanisms, while the fan cowls remain simple enclosed structures. This segmentation eliminates the need for integrated complex opening systems that would affect the entire nacelle.
Solution Approach 2:
The opening systems and maintenance devices are extracted from the fan cowl structure and relocated to the thrust reverser half structure. This allows the thrust reverser to be accessed and maintained independently without involving the fan cowl opening mechanisms.
Data Source
Figure 1
Figure 2
Figure 3A~3B
AI summary
An assembly is provided for an aircraft propulsion system (20). This assembly includes a fixed structure (54) and a nacelle (22). The nacelle (22) includes a first fan cowl (36A) and a first thrust reverser section (100A) adjacent the first fan cowl (36A). The first fan cowl (36A) is movably attached to and arranged on a first side of the fixed structure (54). The first fan cowl (36A) is configured to move between a first fan cowl closed position and a first fan cowl second position. The first thrust reverser section (100A) is movably attached to and arranged on the first side of the fixed structure (54). The first thrust reverser section (100A) is configured to move between a first thrust reverser section closed position and a first thrust reverser section open position when the first fan cowl (36A) is in the first fan cowl closed position.