Aircraft Hidden-Door Thrust Reverser for Reduced Forward-Flight Turbulence

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Solution Overview

Problem

Existing thrust reverser systems in aircraft propulsion systems suffer from flow obstructions and turbulence due to the arrangement of components when stowed, which affect aerodynamic efficiency during typical forward flight.

Innovation Solution

The system incorporates translating sleeves with integrated blocker doors and actuation mechanisms that house thrust reverser components within cavities when stowed, ensuring a smooth bypass flow path by minimizing obstructions and turbulence.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If thrust reverser components are arranged in conventional configurations, then the thrust reverser system can provide reverse thrust function, but flow obstructions and turbulence occur during forward flight reducing aerodynamic efficiency

Engineering Contradiction:
Improvethrust reverser functionVSAvoidflow obstructions and turbulence
Core Design Contradiction:
Ease of manufactureVSObject-affected harmful factors

Solution Approach 1:

The blocker doors are extracted from the conventional exposed position and placed inside hidden cavities within the translating sleeves. During forward flight, the blocker doors remain concealed within these cavities, eliminating flow obstructions and turbulence. The cavities are specifically designed to house the blocker doors while maintaining a smooth external surface that allows uninterrupted airflow.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The blocker doors are nested within the translating sleeves, which themselves are nested within the engine nacelle structure. This multi-level nesting arrangement allows the thrust reverser components to be compactly stored during forward flight, presenting a streamlined profile to the airflow while remaining accessible when reverse thrust is required.

Inventive Principle:
Principle #7Nested doll (Nesting)

2Device complexity

If thrust reverser components are exposed during forward flight, then the system structure is simplified, but aerodynamic performance and efficiency are reduced due to drag and turbulence

Engineering Contradiction:
Improvesystem structureVSAvoidaerodynamic efficiency
Core Design Contradiction:
Device complexityVSLoss of energy

Solution Approach 1:

The translating sleeves are designed to dynamically transition between two positions: during forward flight, they translate to a retracted position where the blocker doors are concealed within hidden cavities, minimizing drag; during reverse thrust operation, they translate to an extended position where the blocker doors are deployed. This dynamic positioning system allows the structure to adapt to different flight conditions, optimizing aerodynamic efficiency without sacrificing structural simplicity.

Inventive Principle:
Principle #15Dynamics

3Object-affected harmful factors

If blocker doors are concealed within cavities, then flow path is smoothed and drag is reduced, but the actuation mechanism becomes more complex

Engineering Contradiction:
Improveairflow disruptionsVSAvoidactuation mechanism
Core Design Contradiction:
Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The actuation mechanism is merged with the translating sleeve structure itself. The translating sleeve serves dual functions: it acts as both the aerodynamic fairing that conceals the blocker doors and the actuating element that deploys them. By integrating these functions into a single component, the patent reduces the overall complexity of the actuation system while maintaining smooth airflow during forward flight.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The translating sleeve is designed as a multi-functional component that simultaneously serves as: (1) the aerodynamic fairing that smooths airflow, (2) the housing for the hidden cavities containing blocker doors, and (3) the actuating mechanism for deploying the blocker doors. This universal design consolidates multiple functions into a single element, reducing the need for separate complex actuation systems.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Data Source

PatentEP3943737B1Hidden door thrust reverser system for an aircraft propulsion system
Publication Date: 2025.08.20 ROHR INC
  • EP3943737B1 patent drawingFigure 1
  • EP3943737B1 patent drawingFigure 2
  • EP3943737B1 patent drawingFigure 3

AI summary

A thrust reverser system (34) is provided that includes a sleeve (52), a fixed cascade structure (94) and a blocker door (100). The fixed cascade structure (94) is within a cavity (80) of the sleeve (52) when the sleeve is in a sleeve stowed position. The blocker door (100) is within the cavity (80) of the sleeve (52) when the sleeve (52) is in the sleeve stowed position and the blocker door (100) is in a blocker door stowed position. The blocker door (100) projects in a radial inward direction away from the sleeve (52) towards the centerline (42) when the sleeve (52) is in a sleeve deployed position and when the blocker door (100) is in a blocker door deployed position. The blocker door (100) includes a pivot attachment (138) fixed at an end of the blocker door. The pivot attachment (138) is configured to move in a forward direction from a first location to a second location.