Improved Hypersonic Aircraft Flight Control System

Aerospace

Improved Hypersonic Aircraft Flight Control System (LAR-TOPS-364)

Recessed, angled lift-augmenting magnetohydrodynamic patch electrode

Overview

Researchers at NASA’s Langley Research Center have designed an improved electrode-based system for guidance, navigation and control of aircraft or spacecraft moving at hypersonic speeds in ionizing atmospheres. The system is composed of two electrodes that are recessed into angled channels on the surface of a craft’s thermal protection system (TPS) and an electromagnet positioned beneath the craft’s TPS. The system operates based on the principles of magnetohydrodynamics (MHD) and uses energy harvested from the ionized flow occurring during flight at hypersonic speeds to power the electromagnet and generate large Lorentz forces capable of augmenting lift and drag forces to steer and control the craft. The energy harvested can alternatively be stored for later use. This improved design increases electrode separation from the shock layer and decreases thermal loads experienced by the electrodes to mitigate thermal degradation.

The Technology

NASA’s MHD patch technology is composed of two electrodes positioned a prescribed distance apart recessed into angled channels on the surface of the TPS of an aircraft or spacecraft and an electromagnetic coil placed directly below the electrodes with the magnetic field protruding out of the surface. Note that the recessed/angled MHD patch described here is a special version of the original MHD patch described in LAR-TOPS-363. During hypersonic flight, the conductive ionizing atmospheric flow over the surface permits current to flow between the two electrodes. This current is harnessed to power the electromagnet which in turn generates strong Lorentz forces that augment lift and drag forces for guidance, navigation, and control of the craft. Alternatively, the current can be used to charge a battery. Changing the size of the MHD patch (e.g., the length or distance between the electrodes), the strength of the electromagnet, or the direction of the magnetic field enables tuning of generated forces for a given craft design. Multiple MHD patches can be leveraged on a single craft. In-silico evaluation of the non-recessed, non-angled MHD patch technology on select aeroshell designs for mock entry into planetary atmospheres has been performed. A single 1m2 MHD patch exerts forces up to 200 kN under simulated Neptune atmosphere entry that can be used to control a craft.

NASA Image Library: https://www.nasa.gov/offices/oct/images/office-of-the-chief-technologist-history-nasa-is-with-you-when-you-fly/nasa-is-with-you-when-you-fly-supersonic-passenger-air-travel

Elements of MHD patch with recessed angled electrodes integrated with a blunt body aeroshell of a spacecraft

Benefits

Improves performance: Increases electrode separation from the shock layer thereby decreasing thermal loads on the electrodes.
Generates large lift and drag forces: Predecessor technology generates forces up to 200 kN under Neptune atmosphere reentry conditions which are projected to be similar to Earth.
Harvests power: Current generated from skimming of ionizing atmospheres can be stored for later use
Is radar-silent: Non-protruding and projected to have minimal radar signature.
Enables larger payloads to be delivered faster: Facilitates entry of larger, heavier craft into planetary atmospheres (including earth) at higher speeds.

Applications

Aerospace and defense: Guidance, navigation, and control of hypersonic aircraft and spacecraft; power harvesting; aerocapture

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Technology Details

Category Aerospace

Reference Number LAR-TOPS-364

Case Number(s) LAR-20037-1

Patent(s) (pop-up blockers must be disabled)

Papers New Magnetohydrodynamic (MHD) Lift Concept for More Efficient Missions to Mars and Neptune. Conference Paper. December 29, 2021. https://arc.aiaa.org/doi/abs/10.2514/6.2022-0934 New Magnetohydrodynamic (MHD) Lift Concept for More Efficient Missions to Mars and Neptune. Presentation. January, 2022. https://ntrs.nasa.gov/citations/20210025128 Effect of Plasma Sheaths on Earth Re-entry MHD Processes. December 29, 2021. https://arc.aiaa.org/doi/10.2514/6.2022-0980

Tags:

entry descent landing ESL magnetohydrodynamic MHD avionics electronics hypersonic steer control navigate energy harvest aerocapture lift drag

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Source NASA Image Library: https://www.nasa.gov/image-feature/jpl/entering-the-martian-atmosphere-with-the-perseverance-rover

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NASA’s MHD patch technology consists of two electrodes positioned a prescribed distance apart on the surface of the TPS of an aircraft or spacecraft and an electromagnetic coil placed directly below the electrodes with the magnetic field protruding out of the surface. During hypersonic flight, the conductive ionizing atmospheric flow over the surface enables current to flow between the two electrodes. This current is harnessed to power the electromagnet which in turn generates strong Lorentz forces that augment lift and drag forces for guidance, navigation, and control of the craft. Alternatively, the current can be used to charge a battery. Changing the size of the MHD patch (e.g., the length or distance between the electrodes), the strength of the electromagnet, or the direction of the magnetic field enables tuning of generated forces for a given craft design. Multiple MHD patches can be leveraged on a single craft. In-silico evaluation of the MHD patch technology on select aeroshell designs for mock entry into planetary atmospheres has been performed. A 1m2 MHD patch exerts forces up to 200 kN under simulated Neptune atmosphere entry, significantly increasing the lift/drag (L/D) ratio for the aeroshell investigated. This value is the same order of magnitude as the “whole body” drag and lift forces computed for the aeroshell suggesting the generated forces can be used to control a craft.

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