Distributed Electric Tail Rotor Power Allocation for Helicopter Yaw Control

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Traditional tail rotors in helicopters suffer from issues such as blade stall, inefficiency due to interaction with main rotor airflow, noise pollution, and structural integrity threats, along with power consumption imbalances during varying flight modes.

Innovation Solution

An electrically distributed yaw control system with a power management system that monitors flight parameters to allocate power between the power system and tail rotor motors, optimizing power usage based on flight mode, airspeed, maneuvers, and power demand, and includes a shroud and multiple tail rotors with variable rotational speed motors to reduce noise and enhance efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Power

If the power system is sized to provide peak power values for tail rotors, then the power system can meet maximum power demands, but the required size of power system components increases

Engineering Contradiction:

Improvepeak power capabilityVSAvoidpower system component size

Core Design Contradiction:

PowerVSWeight of stationary object

Solution Approach 1:

The patent implements dynamic power allocation where the tail rotor power demand is continuously adjusted based on real-time flight conditions (hover, forward flight, maneuvers). The power management system monitors flight parameters and dynamically redistributes power from tail rotors to main rotor or vice versa, allowing the power system to be sized for average rather than peak demands while maintaining capability to meet actual power needs during specific flight phases.

Inventive Principle:

Principle #15Dynamics

2Speed

If tail rotors rotate at high angular velocities to provide adequate aerodynamic responses, then the aerodynamic response improves, but noise increases

Engineering Contradiction:

Improvetail rotor angular velocityVSAvoidnoise

Core Design Contradiction:

SpeedVSObject-generated harmful factors

Solution Approach 1:

The system dynamically adjusts tail rotor rotational speed based on flight conditions. During forward flight where aerodynamic response requirements are lower, the tail rotors operate at reduced speeds, significantly reducing noise from blade rotation and vortex interaction. During hover or maneuvering phases, the system increases tail rotor speed to provide adequate aerodynamic response, thus optimizing the balance between performance and noise across different flight regimes.

Inventive Principle:

Principle #15Dynamics

3Reliability

If the power system allocates maximum power to tail rotors during all flight modes, then the tail rotors can respond to all flight conditions, but power consumption efficiency decreases

Engineering Contradiction:

Improvetail rotor response capabilityVSAvoidpower consumption efficiency

Core Design Contradiction:

ReliabilityVSUse of energy by moving object

Solution Approach 1:

The power management system continuously monitors flight parameters (airspeed, flight mode, power demand) and dynamically allocates power to tail rotors based on actual requirements. During forward flight where anti-torque requirements are reduced, the system decreases power allocation to tail rotors and redirects it to the main rotor or other systems. During hover or high-maneuverability phases, power allocation increases automatically, thus maintaining reliability while optimizing energy efficiency across different flight modes.

Inventive Principle:

Principle #15Dynamics

4Device complexity

If traditional mechanical linkages are used to drive tail rotors, then the system structure is simple, but the system cannot dynamically adjust power allocation based on flight mode

Engineering Contradiction:

Improvesystem structureVSAvoidpower allocation adaptability

Core Design Contradiction:

Device complexityVSAdaptability or versatility

Solution Approach 1:

The patent replaces traditional mechanical linkages with an electrically distributed system where independent electric motors drive each tail rotor. This substitution enables dynamic power allocation through electronic control systems that monitor flight conditions and adjust motor power delivery in real-time. The electrical system allows for sophisticated power management strategies including mode-based allocation, load balancing across multiple tail rotors, and integration with the overall aircraft power system, providing adaptability that mechanical systems cannot achieve.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The system improves yaw control efficiency, reduces noise emissions, enhances structural protection, and optimizes power consumption by dynamically adjusting power allocation and tail rotor operation, addressing the drawbacks of traditional tail rotors.

Implementation Method 1

one or more tail rotors including a motor rotatably coupled to the tailboom

Methodology Applied

Scientific EffectElectromagnetic conversion: Electromagnetic Induction

Data Source

PatentUS11866162B2Power management systems for electrically distributed yaw control systems

Publication Date: 2024.01.09 TEXTRON INNOVATIONS INC

AI summary

An electrically distributed yaw control system for a helicopter having a tailboom and a power system includes one or more tail rotors including a motor rotatably coupled to the tailboom and a power distribution unit. The power distribution unit includes a power management monitoring module configured to monitor one or more flight parameters of the helicopter and a power management command module configured to allocate power between the power system and the one or more tail rotor motors based on the one or more flight parameters of the helicopter.