Research-Single Source Information Extraction: 'Aircraft Infrared Principles, Signatures, Threats..'

'Aircraft Infrared Principles, Signatures, Threats, and Countermeasures (U)' by Jack White is a supplemental text for EW short courses as administered at the Naval Air Warfare Center Weapons Division (NAWCWD) in California; with the document being from 2012. Per the abstract, this "is intended for a general audience without an infrared (IR) background who is looking for a practical overview of the field directed toward the problems of aircraft defense. (p.3)" and ''The object is to convey the key concepts primarily through drawings and images (p.3)." White (2012) does state that a more robust overview of the topic is limited due to the vast amount of theory concerning this topic and that the material (regardless of prior 'inadequacy') should provide a basis to work from. This document comprises 116 pages (excluding reference materials/sections) and is divided into topics. While an exhaustive listing of the information is not performed, critical areas for further reference are addressed. The formatting will be based on the topic headings, with page numbers attached when needed.

White (2012, pp. 5-13): Overview

White (2012, p. 5/9) states that the most critical aspect of infrared (IR) for the military is that any object that has heat will emit IR radiation. The author provides that IR is electromagnetic (EM) radiation with wavelengths longer than visible light but shorter than those classed as microwaves. The author states that high aircraft temperatures are related to the engine and exhaust gasses (p.9), with the reflections and emissions allowing for passive detection and creating vulnerabilities associated with IR-guided missiles and search/track systems. Next, the author provides an overview of the consequences; beginning with the differences between detection by radar and passive detection (i.e., transmitter/receiver vs emissivity) [p. 10]. After this, a brief introduction to an IR-guided missile (i.e., Sidewinder) is given before White (2012) addresses the proliferation of these weapons and systems in the present (pp.11-12). After this, the author addresses three types of defense relevant for aircraft, which are: impression of emissions, a warning system for launch detection and cueing countermeasures, and countermeasure devices and systems (Offboard [e.g., decoys] and onboard [e.g., jammers] (p.13). In addition, the author also states, "the intensity of an aircraft’s IR emissions determines the distance at which a missile can acquire and track the aircraft and the intensity of the countermeasure that is required to protect it." and "The IR signature of an aircraft is the total of its detectable emissions and reflections.." and "significant reductions in the range at which missiles can acquire an aircraft can be achieved through signature suppression...aircraft engines are the primary source of IR emissions (radiation), the greatest initial gain in signature reduction is usually achieved through engine suppression." (pp. 13-14). The author does provide other information, appearing to be addressed in detail later, before concluding this section.

White (2012, pp.14-32): Principles of IR for Aircraft

Beginning this section White (2012) provides some history for the term infrared and states that there is little universal agreement on the term and the nuances involved in the subject matter. White (2012) moves to define IR and the speed of light in a vacuum with lower rates in transparent media (i.e., air or glass). Of note, "The speed of propagation of an electromagnetic wave through a medium is a function of the material properties of permeability and permittivity." (p.19). and :

"Frequency and wavelength are related by speed. The length of a wave is equal to the propagation speed in that medium divided by the frequency. Frequency does not change as a wave enters or exits a medium, so the length of a wave in a slower medium will be shorter than in a vacuum. Locations in the IR part of the spectrum are usually specified by wavelength rather than frequency. The common unit of wavelength is micrometers (um)." (White, 2012, p. 19/15)

White (2012) also states that another related term is wave number before supplying information on how IR interacts with matter and its place in the EM spectrum (p.20-21). Of these: reflection, refraction, absorption, and emissivity are consistent with INT collections coursework. The others listed by White (2012, p. 20) are scattering, interference, transmissive, and polarizing. Afterward, the author notes three important sub-bands to military considerations [Figure 13, p. 22]; with the MWIR being implied as a primary concern.

White (2012, pp. 22-26] supplies, defines and explains three terms: irradiance (i.e., the density of radiant power that is incident on a surface), radiant intensity (i.e., the angular power density from the source, with importance for detection susceptibility and analogous [but different to] radar cross section {RCS}), and radiance (i.e., intensity per unit area or 'brightness'). In addition, White (2012, pp.27-30) shows the connection between these three terms and the relationship to IR. It is implied that these could impact the contrast (which makes possible target detection) and target detection and also notes the role context influences target detection (p.27). White (2012, pp.33-37) covers the domains of distribution (i.e., spectral, spatial, temporal, and polarizing), which are considered fundamental for scenarios; and covers emissivity from solids (pp. 29-35) and gases (pp. 35- 36). Finally, key points are provided (pp. 36-37).

White (2012, pp. 33-61): Aircraft IR Signatures

The author, White (2012), begins this section by emphasizing that the signature of an aircraft creates susceptibility; and, "The word signature is widely used but can be misleading because nothing about an aircraft’s IR signature uniquely identifies the aircraft type. Signature usually means an aircraft’s total contrast intensity;.." (p. 37), emphasizing the complexity as a factor. Areas associated with the signature are engine parts, exhaust plumes, and the airframe (White, 2012, p. 38), each having a different spectral distribution (See Figures 26 and 27 from the author). On pages 40 to 50 (or 36 for document-based pagination), White (2012) details the engine (inclusive of

spectral distribution), exhaust plumes (pp. 42-45), and the airframe [ with airframe variability, background factors, and Aerodynamic Heating being addressed (pp.45-49). Key points are also provided.

White (2012, pp. 46-61): Propagation and Detection

White (2012) begins this section by saying that direct emissivity is not a factor but is assessed with the remnants in the atmospheric path, contrasted with the natural background (p. 50). On page 51, White (2012) begins to supply information and concepts for the atmosphere as a medium; with important aspects being a spectrally selective nature (with MWIR being "characterized by deep absorption regions separated by regions of relatively high transmission called atmospheric 'windows.'"), and the two main mechanisms for this selectivity are molecular absorption and scattering.

White (2012) states that out of the gasses that comprise the atmosphere, only water vapor and CO2 have the resonant frequencies [NOTE: MOL ABS EMIT RAD @ NAT RESOFREQ->GEN SPECTREG WITH MAJRAD ABS] that exist within the MWIR category; which also have an impact on propagation. Concerning the spectral regions (ref: note above), White (2012, p. 52/48) "depth and spectral width of the absorption regions depend upon the number of molecules in the path, so absorption width is greater for longer path lengths and greater at lower altitude, where air density is higher.".

White (2012) states that the density of CO2 is a direct function of pressure, and water vapor consists of pressure and temperature: with water vapor decreasing (at an increased rate) as altitude increases (NOTE: D/T RELLOW SATDENSTY in DECTEMP and @ ALT >/== 30,000 {subnote. Consistent with area ==yes} CAN ELIMH2O as PROPFX). The author asserts that this is the most attenuated by exhaust plumes, due to both CO2 and water vapor being the two main products that result from combustion. Per the author, White (2012, p. 52): "Absorption by water vapor and CO2 in the air occurs at these same lines. The high temperature and pressure of the exhaust gases cause broadening of the emission lines, thus allowing passage through the absorbing atmosphere." Following this, the author defines the terms apparent and at source with the former meaning, "Any IR quantity that has atmospheric influence is referred to as “apparent.” Almost all IR values are apparent, although the name is frequently omitted."; and the latter being, "Mathematically backing out the influence of atmosphere can be done but usually with a high degree of uncertainty. Any apparent value that has had atmosphere Wavelength artificially removed is referred to as “at source.” (p.53-54) Other items of note are that all tactical aircraft are viewed through some sort of atmospheric path, and a result of spectral selectivity is the spectral distribution at source, transmission of the atmosphere, and wavelength band as it relates to sensor technology.

White (2012, p. 54) discusses path radiance and sky background before moving into reception and detection. When White (2012, p. 55) addresses reception and detection, the author makes note that many share the same functional elements such as optics, filters, a detector (Which "converts received radiant power into an electrical signal."[p.56]), and processing electronics. The author addresses optics from pages 56-59 and covers topics such as lenses and filters; before moving into detectors such as thermal and photon; before concluding with detector arrays. The author covers some other issues, then transitions into the following subsection.

White (2012, pp. 62-78): IR-Guided Missile Principles

This subsection by White (2012) briefly relates to the principles involved in IR-Guided missiles. Areas of note are intercept course (p. 67), servo (p. 68), window (pp. 68-69). Others are optics, emissions and response, and some information concerning spectral response is given (pp. 68- 78); before the evolution of IR-Guided missile tech is given (pp. 79-83). One key takeaway is: "Missiles fly an intercept course to target using proportional navigation. Proportional navigation requires a target tracker that is independent of the missile body. The target tracker is the window through which the missile can be countered." (p. 82)

White (2012, pp. 79-92): IR Countermeasures

This section provides information on off-boar-board countermeasures such as decoys (pp. 84-87) and flares (pp. 87/83- 91/87); before transitioning into other topics relevant to their use. One key takeaway is "IR missiles are passive, and there is no currently fielded system capable of identifying missile type and, consequently, establishing the most effective decoy." (p.93) Another is: "The objective in decoy countermeasures is to pull the track of the missile away from the target until the target is no longer in the missile FOV. Basic parameters in decoy countermeasures are in-band intensity and separation rate versus time." (p. 96)

White (2012, pp. 93-102): Jammer Countermeasures

White (2012, pp. 97/93-106/102) details information for onboard countermeasures such as jammers; before addressing other issues (pp. 107-114) before transitioning into the following subtopic. One key takeaway is, "The objective of jammer countermeasures is to inject a signal into the missile target tracker that causes the tracker to push away from the real target aircraft." (p. 102) Another is information concerning UV (pp.112).

White (2012, pp. 111-116): Directions and Challenges

Generally, this section comprises information from White (2012) which focuses on the challenges and how future technology could impact the outcome. Areas of note are aircraft IR signatures (p. 116), IRST (p.118), and directions in countermeasures (pp. 118-121).

Project Information

Resource/Reference Number for Related Personal Research (Non-Commercial) Project- Stealth Technology in the US Military: Past, Present, and Future". Reference Numbers are not currently alphabetized; they will be added to Zotero for the final work, and subsequently, the current numbering will not reflect the end number assigned to a utilized reference. [REF(0007/0057)].

Project Keywords (Potential):

Stealth Technology, IRST, United States Air Force (USAF), B-2 Spirit, Department of Defense (DOD) Next Generation Air Dominance (NGAD), Collaborative Combat Aircraft (CCA), Metamaterials, Nanotechnology, Sensor Technology, EM, SR-71, Strikestar 2025

Project Description:

Given that the United States Air Force is currently focusing on Next Generation Air Dominance (NGAD) and Collaborative Combat Aircraft (CCA), an opportunity to examine the past, present, and future of military aircraft has been presented. Specifically, the focus of this project will be an overview of stealth and sensing technology, with a more creative aspect stemming from a 'far future' perspective. Initially, the paper will address background information before examining past systems. Next, the project will explore the present aircraft; before providing a limited view of the near future (i.e., NGAD and CCA). Finally, this project will examine some 'far future' iterations given continued advancement in the related scientific backgrounds.

Reference

White, J. R. (2012). Aircraft Infrared Principles, Signatures, Threats, and Countermeasures: Defense Technical Information Center. https://doi.org/10.21236/ADA566304

Important Questions

1. Regarding quantum sensing [Far-future]: Blasone et al. (2011) implies that an underlying quantum state could impact or affect macroscopic systems/events/etc. Topologically, this is observable given the information from McCormick (2023)[Propaganda Blog Post], an article describing a study exploring topological similarities within the Earth's weather patterns. Suppose this holds, given that Blasone et al. (2011) assert that various materials can be conceptualized as a macroscopic quantum system and that the matter comprising biological life can (somehow) be reduced to a quantum level. Upon introducing any macroscopic material that transfers energy into the larger environment (e.g., thermal radiation visible in IR wavelengths, from a human body or piece of equipment), would a defined area within a sensor area' create an observable change? What are the potential limits or areas that could be prone to deception/interference, given that the underlying 'energy state' would be monitored? Monitoring, for example, the excitation of electrons in a given area.

2. Stealth/Low-Observable/Cloaking (Far-Future): If there is a substantial increase in computational power and capability, inclusive of leveraging AI/ML and a quantum state can be 'engineered'; if a progression occurs: Is the ability to create an adaptive 'quantum state' within the larger structure feasible for stealth/low-observability/cloaking, for example, by manipulating the underlying energy to match the underlying environmental energy signatures/states. Can the creation of a 'counterwave' (CUNY, 2023) be used similarly or comparably? If so, how would that use be detected, and what are other applications?

Additional Sources for Consideration

I have not listed (needs an investigation before use) Sources: 'NI656123BU' for Glass, 'Med10x12-23PMC' for Metamaterials, and 'StaticTobleronePencil23' for metamaterials.

1. Alu (n.d.)- Background mat, used for supporting initial overview.

2. Annamdas and Soh (2019)- Use of metamaterials/piezoelectric for monitoring structures, structural monitoring for integ. etc., and Fig. 1

3. Berkowitz (2023)- Glass

4. Blasone et al. (2011)-Macro and Quantum <full access needed>

5. CUNY Advanced Science Research Center (2023)- Wave Cancellation

6. Danaci et al. (2023)- Interesting read, explore QSE more.

7. De Lisio et al. (2023)- Glass

8. Ecole Polytechnique Federale de Lausanne (2023)-Tech current mech. oscillator

9. Jeong and Lim (2023)- Metamaterial/Low_Frequncy Absorber

10. Norwegian University of Science and Technology (2023)- Quantum Sensing and advo. Basic research needed for adv.

11. Penn State (2023)- Glass

12. UCLA Engineering Institute for Technology Advancement (2023)- Auton. and compvis?

13. Cafe (n.d.), Swinburne University of Technology (n.d.), The University of Tenessee Knoxville (n.d.)- Em Spectrum information, vacuum (e.g., pilot area, etc.) wavelength/size eng. for mitig. (Supp. by INT collection related coursework==Yes)?

References

Alù, A. (n.d.). Engineered Metamaterials Can Trick Light and Sound into Mind-Bending Behavior. Scientific American. https://doi.org/10.1038/scientificamerican1122-42 Annamdas, V. G. M., & Soh, C. K. (2019). A Perspective of Non-Fiber-Optical Metamaterial and Piezoelectric Material Sensing in Automated Structural Health Monitoring. Sensors (Basel, Switzerland), 19(7), 1490. https://doi.org/10.3390/s19071490 Berkowitz, R. (2023). Scientists theorize a hidden phase transition between liquid and a solid. https://phys.org/news/2023-08-scientists-theorize-hidden-phase-transition.html Blasone, M., Jizba, P., & Vitiello, G. (2011). Quantum Field Theory and Its Macroscopic Manifestations: Boson Condensation, Ordered Patterns and Topological Defects. IMPERIAL COLLEGE PRESS. https://doi.org/10.1142/p592 Cafe, K. B. R. (n.d.). Frequency—Wavelength Conversion Table. Retrieved August 15, 2023, from https://www.rfcafe.com/references/electrical/frequency-wavelength-conversion-table.htm CUNY Advanced Science Research Center. (2023). No longer ships passing in the night: These electromagnetic waves had head-on collisions. https://phys.org/news/2023-08-longer-ships-night-electromagnetic-head-on.html Danaci, O., Zhang, W., Coleman, R., Djakam, W., Amoo, M., Glasser, R. T., Kirby, B. T., N'Gom, M., & Searles, T. A. (2023). ManQala: Game-inspired strategies for quantum state engineering. AVS Quantum Science, 5(3), 032002. https://doi.org/10.1116/5.0148240 Di Lisio, V., Gallino, I., Riegler, S. S., Frey, M., Neuber, N., Kumar, G., Schroers, J., Busch, R., & Cangialosi, D. (2023). Size-dependent vitrification in metallic glasses. Nature Communications, 14, 4698. https://doi.org/10.1038/s41467-023-40417-4 Ecole Polytechnique Federale de Lausanne. (2023). A quantum leap in mechanical oscillator technology. https://phys.org/news/2023-08-quantum-mechanical-oscillator-technology.html Jeong, H., Nguyen, T. T., & Lim, S. (2018). Subwavelength Metamaterial Unit Cell for Low-Frequency Electromagnetic Absorber Applications. Scientific Reports, 8(1), 16774. https://doi.org/10.1038/s41598-018-35267-w Norwegian University of Science and Technology. (2023). Quantum sensors paving the way for new technologies. https://phys.org/news/2023-08-quantum-sensors-paving-technologies.html Penn State. (2023). LionGlass: New Type of Glass That's Greener and 10x More Damage Resistant. https://scitechdaily.com/lionglass-new-type-of-glass-thats-greener-and-10x-more-damage-resistant/ Swinburne University of Technology. (n.d.). Electromagnetic Spectrum | COSMOS. https://www.astronomy.swin.edu.au/cosmos/E/Electromagnetic+Spectrum The University of Tenessee Knoxville. (n.d.). The EM spectrum. Retrieved August 15, 2023, from http://labman.phys.utk.edu/phys222core/modules/m6/The%20EM%20spectrum.html UCLA Engineering Institute for Technology Advancement. (2023). Universal linear processing of spatially incoherent light through diffractive optical networks. https://phys.org/news/2023-08-universal-linear-spatially-incoherent-diffractive.html University at Buffalo. (2023). "Quantum Avalanche" – A Phenomenon That May Revolutionize Microelectronics and Supercomputing.'https://scitechdaily.com/quantum-avalanche-a-phenomenon-that-may-revolutionize-microelectronics-and-supercomputing/