Retractable VTOL Propulsor Assemblies for Drag Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing VTOL aircraft face challenges in reducing aerodynamic drag during cruise flight, as the rotors and support structures remain in the airflow, leading to inefficiencies in energy consumption and range.
Innovation Solution
The implementation of retractable propulsor assemblies that deploy from a compartment in the aircraft fuselage for vertical take-off, hover, and vertical landing, and are stowed during cruise flight to minimize drag.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If rotors and support structures are kept fixed for VTOL capability, then vertical take-off and landing function is maintained, but aerodynamic drag increases during cruise flight
Solution Approach 1:
The rotor assembly is made dynamically configurable, transitioning from a fixed state during VTOL operations to a retracted state during cruise flight. The rotor can be rotated into a horizontal position for takeoff and landing, then retracted into a storage compartment to minimize drag during forward flight, allowing the aircraft to adapt its configuration based on operational requirements.
Solution Approach 2:
The rotor assembly is segmented into separable components that can be independently positioned and stored. The rotor blade assembly is divided from the support structure, allowing the rotor to be extracted and stored in a compartment when not needed for VTOL operations, thereby reducing the harmful aerodynamic drag while maintaining the capability when required.
2Object-affected harmful factors
If rotors are retracted during cruise flight, then aerodynamic drag is reduced, but complexity of deployment mechanism increases
Solution Approach 1:
The support structure serves multiple functions: it provides structural support for the rotor during VTOL operations, acts as a mounting mechanism for the rotor assembly, and functions as a storage compartment when the rotor is retracted. This multi-functionality reduces the need for separate components and simplifies the overall deployment mechanism while achieving drag reduction during cruise flight.
3Use of energy by moving object
If rotor assembly is made retractable, then energy efficiency during cruise improves, but structural complexity increases
Solution Approach 1:
The support structure and storage compartment are merged into a single integrated component. The support structure simultaneously provides structural support during VTOL operations and serves as the storage compartment for the rotor during cruise flight. This merging eliminates the need for separate storage structures, reducing structural complexity while maintaining energy efficiency during cruise operations.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Retractable propulsor assemblies (108) for aircraft (900) are described that generate lift during vertical take-off, hover, and vertical landing. The retractable propulsor assemblies (108) are deployed from a compartment in a fuselage of the aircraft to transition the aircraft into vertical flight, and are stowed in the compartment during cruise flight to reduce aerodynamic drag on the aircraft. One embodiment comprises a method of operating a VTOL aircraft. The method comprises deploying the retractable propulsor assembly from the compartment of the fuselage to provide the lift for vertical flight. The method further comprises transitioning the VTOL aircraft from the vertical flight to cruise flight, and stowing the retractable propulsor assembly in the compartment during the cruise flight to reduce the aerodynamic drag on the VTOL aircraft (Fig. 9).