Black Hawk Research Articles

College will ensure student's access to equestrian science program

Case name: Letter to: Black Hawk College, No. 05‐16‐2218 (OCR 10/17/16).

Black Hawk-Down: Adaptation and the Military-Entertainment Complex

This article investigates the non-fiction book Black Hawk Down (1999) by Mark Bowden, Black Hawk Down the movie (2001) directed by Ridley Scott, and the computer game Delta Force: Black Hawk Down (2003). The article suggests that while the movie and the game must be studied as adaptations of the first text, the tools developed by adaptation studies, and that are typically used to study the transfer of narratives from one media form to another, do not suffice to fully describe the ways in which these narratives change between iterations. To provide a more complete account of these adaptations, the article therefore also considers the shifting political climate of the 9/11 era, the expectations from different audiences and industries, and, in particular, the role that what James Der Derian has termed the Military-Industrial-Media-Entertainment Network (MIME-Net) plays in the production of narrative. The article thus investigates how a specific political climate and MIME-Net help to produce certain adaptations. Based on this investigation, the article argues that MIME-Net plays a very important role in the adaptation of the Black Hawk Down story by directing attention away from historical specificity and nuance, towards the spectacle of war. Thus, in Black Hawk Down the movie and in Delta Force: Black Hawk Down, authenticity is understood as residing in the spectacular rendering of carnage rather than in historical facts. The article concludes that scholarly investigations of the adaptation of military narratives should combine traditional adaptation studies tools with theory and method that highlight the role that politics and complexes such as MIME-Net play within the culture industry.

Rock Island Revisited: Black Hawk's Life, Keokuk's Oratory, and the Critique of US Indian Policy

This article examines the writings and oratory of the Sauk tribal leaders Keokuk and Black Hawk in the context of Indian diplomacy at Rock Island Indian agency. While Black Hawk's autobio-graphy Life of Mà-ka-tai-me-she-kià-kiàk (1833) is widely read today, Keokuk's oratory has typ-ically been dismissed as an accommodationist extension of US governmental discourses, as op-posed to Black Hawk's rhetoric of resistance and criticism of the Black Hawk War. Complicat-ing these historical narratives, this article argues that both Black Hawk and Keokuk produced collaborative publications that in similar ways critiqued the management of Indian affairs within networks of Indian agents, traders, and tribal leaders. Black Hawk's Life challenges the legitima-cy of Keokuk's leadership within these networks, but also mounts a more structural critique of the "bad management" of Indian affairs at Rock Island Indian Agency. Keokuk's oratory similar-ly addressed the economic and intertribal ramifications of American expansion, while also imag-ining that the agency of tribal leaders within the Indian Office held a potential to reassert an eco-nomic and social place for the Sauk Nation and the closely allied Meskwaki Nation. Operating through the technologies of the Indian Office, Black Hawk and Keokuk's writing and oratory represent critical instances of institutional negotiation and intervention. Seen together, their oral, scribal, and print publications register the historical dynamics of removal in the Midwest, as it was elaborated and contested at the Rock Island Indian agency.

Cherokee Sister: The Collected Writings of Catharine Brown, 1818–1823 ed. by Theresa Strouth Gaul

Reviewed by: Cherokee Sister: The Collected Writings of Catharine Brown, 1818–1823 ed. by Theresa Strouth Gaul Michael P. Taylor (bio) Cherokee Sister: The Collected Writings of Catharine Brown, 1818–1823 Edited by theresa strouth gaul Lincoln: University of Nebraska Press, 2014 289 pp. Cherokee Sister: The Collected Writings of Catharine Brown, 1818–1823 offers to Americanists and Native Americanists alike a versatile collection of perhaps the earliest published Native American woman author in the United States. Until Theresa Strouth Gaul gathered and recontextualized Catharine Brown's (Cherokee) letters and diary alongside other nineteenth-century representations of Brown in Cherokee Sister, scholars had remembered Brown largely through an 1825 American Board of Commissioners for Foreign Missions publication, Memoir of Catharine Brown, a Christian Indian of the Cherokee Nation (1825). As its title suggests, Memoir narrates Brown as unilaterally assimilated into white Protestantism and celebrates her as a model Christian convert. As a result, contemporary scholarship has likewise often reduced Brown to narratives of isolated assimilation rather than placing her either within her specific Cherokee community or within broader conversations with such now-canonized contemporaries as William Apess (Pequot), Elias Boudinot (Cherokee), and Black Hawk (Sauk). By privileging Memoir's oversimplification of Brown over the inherent complexities and contexts of Brown's own writings, scholars have so far, albeit unintentionally, disconnected her from such critical contemporaneous and contemporary issues as Native American sovereignty, land, kinship, and the ongoing epidemic of sexual-colonial violence against Native American women. As Gaul suggests in her carefully constructed editor's introduction, Cherokee Sister responds to the ongoing reduction of Brown by "put[ting] the pen back in her hand" (2). By doing so, Cherokee Sister not only restores autonomy to Brown's [End Page 218] writings, it also reasserts Brown's articulate agency as an early Cherokee woman who interpreted, taught, exhorted, and wrote toward her stated goal to "be useful to [her] people" (73). Beyond republishing the writings of yet another important early Native American woman writer within the growing body of Native American literature, Cherokee Sister will prove valuable to a wide range of college classrooms. Brown's writings directly address issues central to American literary studies, Native American studies, Cherokee studies, religious studies, and gender studies. Gaul's collection also offers ample analytical opportunities for classroom studies of nineteenth-century biography, autobiography, epistolary writing, and diary writing. While Gaul gracefully places Cherokee Sister at the "nexus" of each of these disciplines, however, she places the responsibility onto teachers and students to construct the more comprehensive context(s) necessary in order to situate Brown in a more direct relationship with any one of these disciplinary frameworks (5). In terms of Brown's place within current discussions of Native American or Cherokee studies, for example, Gaul places Brown's writing in conversation with Cherokee scholars Daniel Heath Justice and Jace Weaver in order to emphasize her place within the Cherokee literary tradition. Yet Gaul has not fully reconstructed the relationships between Brown and such contemporaneous Cherokee women writing and community-specific literary activism as the 1817 Cherokee women's petition against Indian Removal. It is likewise up to the teacher or student to analyze Brown in conversation with such broader contemporary currents in indigenous feminism, indigenous literary nationalism, and transindigeneity. Although Gaul could have claimed a greater significance for Cherokee Sister by situating Brown's writing more overtly within the long tradition of Cherokee women writing or within specific branches of current Native American and indigenous studies, Cherokee Sister's ability to speak to so many interconnected contexts and issues will service a range of college classrooms toward a more nuanced understanding of the complexities of agency and adaptation in nineteenth-century Native American literatures. I am eager to work alongside my students to (re)connect Brown further to the intricate networks of early and contemporary Native American women writers as part of my indigenous and American literature classes. [End Page 219] Michael P. Taylor Brigham Young University Michael P. Taylor michael p. taylor is assistant professor of English at Brigham Young University. He teaches in the fields of indigenous studies, American studies, and nineteenth-century American literature. His scholarship focuses on indigenous literary...

Impact of Adverse Environmental Conditions on Rotorcraft Operational Performance and Pollutant Emissions

It is anticipated that the contribution of rotorcraft activities to the environmental impact of civil aviation will increase in the future. Due to their versatility and robustness, helicopters are often operated in harsh environments with extreme ambient conditions. These severe conditions not only affect the performance of the engine but also affect the aerodynamics of the rotorcraft. This impact is reflected in the fuel burn and pollutants emitted by the rotorcraft during a mission. The aim of this paper is to introduce an exhaustive methodology to quantify the influence adverse environment conditions have in the mission fuel consumption and the associated emissions of nitrogen oxides (NOx). An emergency medical service (EMS) and a search and rescue (SAR) mission are used as case studies to simulate the effects of extreme temperatures, high altitude, and compressor degradation on a representative twin-engine medium (TEM) weight helicopter, the Sikorsky UH-60A Black Hawk. A simulation tool for helicopter mission performance analysis developed and validated at Cranfield University was employed. This software comprises different modules that enable the analysis of helicopter flight dynamics, powerplant performance, and exhaust emissions over a user-defined flight path profile. For the validation of the models implemented, extensive comparisons with experimental data are presented throughout for rotorcraft and engine performance as well as NOx emissions. Reductions as high as 12% and 40% in mission fuel and NOx emissions, respectively, were observed for the “high and cold” scenario simulated at the SAR role relative to the same mission trajectory under standard conditions.

From the Sands of the Ogaden to Black Hawk Down: The End of the Cold War in the Horn of Africa

From the Ogaden War to the Black Hawk Down incident, the Horn of Africa was a theatre of events with far-reaching international consequences. This paper argues that the distinctive process leading to the end of the bipolar conflict in the Horn is crucial to understanding the role of this region both during and after the Cold War. Through an extensive analysis of the period 1985–1991, this article explains why only a few years after the ‘burial’ of SALT II in the sands of the Ogaden, the superpowers withdrew from the region which had been the symbol of the failure of détente. Similarly, an analysis of the end of the Cold War is paramount to understanding why, after the break-up of the USSR, the Horn of Africa hosted one of the most tragic episodes of post-Cold War US foreign policy.

Thinking Mythologically: Black Hawk Down, the “Platoon Movie,” and the War of Choice in Iraq

While preparing the 2003 invasion of Iraq, President Bush invited his advisors to screenings of Black Hawk Down (2002). “Bush . . . told his aides that America’s hasty exit from Somalia after 18 soldiers died in the 1993 raid made famous in the movie . . . emboldened America’s terrorist enemies” to attack us on September 11. This study explains the ideological force of Black Hawk Down by framing it as the culmination of developments in American national mythology, and the mass culture genres that carry it. The “Platoon Movie” developed during WW II propagated a new myth of multi-ethnic American nationality, and a “war imaginary” which figures WW II as the “Good War.” That myth was discredited by defeat in Vietnam; but starting in 1980, American war films, and war-themed science fiction films, seconded the work of neo-conservative policy makers to recuperate the “war imaginary.” This entailed a sharpening of racialist interpretations of international conflict, and tension between the multicultural symbolism of the “platoon” and the idealization of Whites as “real Americans.”

Revisiting the Linkage: PDD 25, Genocide in Rwanda and the US Peacekeeping Experience of the 1990s

ABSTRACTAfter the successful US–UN action in Operation Desert Storm in 1991, by the mid-1990s Washington's enthusiasm for multilateral action had already faded away. This was evident after the ‘Black Hawk Down’ disaster of the US Mission in Somalia in October 1993 and the release of a much more restrictive peacekeeping policy in May 1994 (PDD-25). The US inaction during the following Rwandan genocide in spring 1994 was then seen as the obvious consequence of the American ‘trauma’ in Somalia, as well as the symbol of Washington's withdrawal from peacekeeping commitments. However, in the light of new archival documents a different scenario emerges. This article shows that the consequential link, often stressed by the literature, between the Somali disaster, the release of PDD-25 and American inaction in Rwanda is much less straightforward. This suggests that the policy in Rwanda was not just a consequence of the Somali debacle and that the reasons for US inaction toward the genocide must be gauged within a broader set of factors. The study of Washington's policy in Rwanda thus becomes a significant case to investigate some broader patterns of post-Cold War American foreign policy and to re-evaluate the US peacekeeping experience of the 1990s.

Soybean maturity groups and growth habits in Esfahan conditions

Knowledge of the vegetative and reproductive characteristics of soybean cultivars with different growth habits and maturity groups is essential for the selection of a suitable variety as well as for providing conditions for their growth. In 2008 at a field located in Kholenjan of Esfahan, Iran, nine indeterminate type cultivars of different maturity groups, namely Williams, Wood Worth, Hack, Zane, Black Hawk, Bonus, Steel, S.R.F. and Harcor and one determinate cultivar belonging to maturity group III namely Hobbit, in a complete randomized block design with four replications were evaluated. Indeterminate cultivars and higher maturity group cultivar produced more dry matter. Generally indeterminate cultivars with later maturity had longer main stem and more node, pods and seeds. The determinate cultivar had more lateral branches, and more pods and seed per pod. However, these traits did not show any trend in different maturity groups. Height of the first pod from the ground surface in indeterminate cultivars was higher than of indeterminate ones. Number of pods per main stem nodes, number of seeds per pod in the lateral stems and number of nodes per lateral branches show no significant difference among cultivars. Classification of cultivars based on the above characteristics showed that cultivars with different growth habit had basic differences and some cultivars showed some similarity to maturity groups which did not exist in the present study.

Re-Collecting Black Hawk: Landscape, Memory, and Power in the American Midwest

Re-Collecting Black Hawk: Landscape, Memory, and Power in the American Midwest

Accelerometer-Based Acoustic Control: Enabling Auscultation on a Black Hawk Helicopter

During aeromedical patient transport, acoustic noise levels in excess of 90 dB make auscultation with a stethoscope virtually impossible. Existing approaches to address this noise in literature have relied on the use of either passive shielding of the stethoscope sensing element or active noise cancellation (ANC) with the use of additional reference microphone sensors. These solutions have achieved inadequate performance. In this paper, custom instrumented stethoscopes are used to obtain structural vibration and acoustic data from a UH-60 Black Hawk helicopter. The data show that the structural vibrations contribute significantly more to stethoscope signals than air-borne acoustic noise. Therefore, a novel adaptive acoustic control system using a reference accelerometer is pursued. By varying the levels of acoustic and vibrational noise sources in a controlled laboratory environment, the benefits and limitations of microphone or accelerometer-based active noise control are investigated and compared. Experimentally simulating the field acoustic and vibration characteristics of the UH-60 Black Hawk helicopter, the accelerometer-based ANC system is shown to provide significantly superior performance. The accelerometer-based ANC system yields an average 25-dB reduction in ambient noise levels over the entire relevant frequency range, thereby enabling successful auscultation for the first time in this military aircraft environment.

Red Dreams, White Nightmares: Pan-Indian Alliances in the Anglo-American Mind, 1763–1815 by Robert M. Owens

Reviewed by: Red Dreams, White Nightmares: Pan-Indian Alliances in the Anglo-American Mind, 1763–1815 by Robert M. Owens Adam Jortner Robert M. Owens, Red Dreams, White Nightmares: Pan-Indian Alliances in the Anglo-American Mind, 1763–1815. Norman: University of Oklahoma Press, 2015. 320pp. $32.95. Which is the stronger motivator—hate or fear? This unpleasant but relevant question is at the heart of Robert Owens’ Red Dreams, White Nightmares, an examination of the idea of pan-Indianism in white American politics and society in the early republic. Owens sets out his argument as a corollary to work on Indian-hating by Peter Silver, Patrick Griffin, and others. Hate alone, Owens writes, does not explain policy and policymaking, for “if we remove from our analysis the terror that eighteenth- and nineteenth-century whites felt regarding Indian wars . . . we effectively dehumanize them as badly as Parkman dehumanized his Indian foils.” (8) At key moments, white fears of Indian alliances—as opposed to white indignation at Indian military practice—forced the hands of administrators and generals. Lord Dunmore, for example, launched his 1774 war against the Shawnee and Mingo in part to sate his anxiety over a potential combination of those nations with the Cherokees to the South (50–54). American Indian policy, 1795–1805, was largely dictated by fears of pan-Indian conspiracies—even though the United States had already defeated the Ohio Confederacy in 1795. “[T]he fear itself,” writes Owens, “continued to haunt the frontier,” with imagined alliances among Indian nations, the Spanish, and the French occupying the psychological site of anxiety formerly reserved for the Northwest Confederacy and its desultory British allies (165). Even when there were no Indian coalitions to worry about, Anglo-Americans acted as though there were, and tried to stop them. The potential upshot here—one Owens never really states directly—is that while hate served as a powerful motivator, it was a perpetual long-term anxiety that created the atmosphere in which that hate could be transformed into violence. American armies and politicians always found inciting incidents, but whatever real or imagined outrages were committed by Native Americans, it was the early republic’s “media echo chamber” that turned rumors of pan-Indianism into a public priority (183–84). For twenty-first-century American thinkers and policymakers—stuck with an anxiety-driven media and confronted with the engines of hate in the US and beyond—this formulation of the relationship among hate, fear, and policy is worth thinking about. Is that enough, however, to make Nightmares stand out in the increasingly [End Page 118] crowded field of Native American history, 1763–1815? Owens adds a fair amount of detail to the diplomatic history of Native America. He has mined the archives in several languages, and there are details in this volume that readers will not find even in Greg Dowd’s Spirited Resistance or Richard White’s Middle Ground. Owens also successfully weaves Florida into the story; his two chapters on William Augustus Bowles are the best in the book. The very subtlety of Owens’s argument, however, may obscure its contribution. Hate and fear are near allied, especially in practical politics; some readers may find the exercise of separating them futile. Moreover, Owens is not always clear about the difference between fear of presumed Indian alliances and fear of presumed Indian brutality. The murder of Jane McCrea, for example, was a huge propaganda victory for Patriot forces—but its fearmongering had more to do with a fear of Indians than of Indian alliances (75). When Dunmore fought the Shawnee-Mingo alliance to prevent a broader coalition, were his actions driven by fear or realpolitik? Owens’ point, I suspect, is that we cannot ever separate the two. If so, the real upshot of this book is not Owens’s conclusion about the Black Hawk War. If Owens is right, fear forms policy. If so, then we might do better to think of white frontier society as a quivering mass of nerves—leaping at shadows and shivering under their bedclothes. Griffin’s and Silver’s works are limned with the notion of the white frontiersman as a brutal tactician—hate translated into...

Borderlands, Indigenous Homelands, and North American Settler Colonialism

Borderlands, Indigenous Homelands, and North American Settler Colonialism Elspeth Martini (bio) John P. Bowes. Land Too Good for Indians: Northern Indian Removal. Norman: University of Oklahoma Press, 2016. xiv + 306 pp. Figures, maps, bibliography, notes, and index. $29.95. Michel Hogue. Metis and the Medicine Line: Creating a Border and Dividing a People. Chapel Hill: University of North Carolina Press, 2015. ix + 328 pp. Maps, illustrations, bibliography, notes, and index. $32.95. Both of these books tell histories of peoples whose nineteenth-century homelands fell within the "northern borderlands" surrounding the U.S–Canadian border. And each, in different ways, evokes the struggles of indigenous peoples who attempted to retain their homelands, as settlers and government agents sought to dispossess and expel them. John Bowes' wonderful study of Northern Indian removal encompasses the borderlands of the Great Lakes, but it ultimately tells a (mostly) U.S.–focused history that challenges the customary narrative of Indian removal. Generally such narratives are dominated by the Indian Removal Act and the experiences of the Cherokees. Michel Hogue, in contrast, focuses more directly on the politics of the U.S.–Canadian border, masterfully recreating the world of the early nineteenth-century Northern Plains where the Plains Metis emerged and thrived, only to be excluded during the later nineteenth century by U.S. and Canadian settler regimes. As well as making substantive contributions to North American historiography, these works also contribute to the movement among North American scholars to incorporate theories of "settler colonialism." So while they tell the histories of different peoples, they both frame their narratives with an eye to the more widespread, longer-term dynamics through which North American indigenous homelands became the territories of the United States and Canada. Taking on the long-overdue task of exploring Northern Indian removal, Bowes' Land Too Good for Indians makes an extremely important contribution to American historiography. As in the better-known stories of their Southeastern contemporaries, Indian peoples north of the Ohio River also found themselves marked for "removal" west of the Mississippi. Yet, as Bowes [End Page 416] notes, it is the anti-removal struggles of the Southeastern peoples—and the Cherokees in particular—that feature in leading histories on removal, exemplified by the work of scholars such as Theda Perdue, Michael Green, and Tiya Miles.1 Whereas these narratives have made it into U.S. history textbooks, the experiences of peoples in the North generally receive only a brief cameo in the form of the 1832 Black Hawk War. This is perhaps unsurprising, given that Bowes' book is the first comprehensive removal-focused history of the Old Northwest since Grant Foreman's Last Trek of the Indians (1946). But Land Too Good for Indians does more than simply add a new regional geography to our current understandings of the removal era. Bowes argues that, in order to more fully understand the dynamics of Indian removal, we must go beyond portraying the Indian Removal Act "as a watershed historical event" (p. 7) and instead see it as just "one piece of a larger process" (p. 12). He attributes such conceptual insights to theories of settler colonialism that have become increasingly applied in the North American context by scholars such as Gary Anderson.2 Building on such work, Bowes frames the expropriation of Native homelands during the removal era as "a powerful illustration" (p. 12) of the much-longer history of dispossession that has structured relations between American Indians and the United States. Bowes employs these theoretical insights with a deft hand, exploring how colonialist power structures manifested in specific contexts. This attention to context is reflected in the book's structure. Instead of presenting an all-encompassing "single narrative arc" (p. 6), Bowes introduces the work as a series of case studies that "illustrate the specific facets of a diverse and complex history" (p. 17). In seven succinct and lucid chapters he manages to cover the interrelated histories of various Northern peoples, including groups of Miamis, Delawares (Lenapes), Wyandots, Senecas, Shawnees, Potawatomis, Ojibwes, and Odawas. The first chapter gives an excellent road map into the political culture of the eighteenth- and nineteenth-century Great Lakes region. Beginning with the years of the...

What Does the Trump Administration Mean for the Mérida Agreement?

What Does the Trump Administration Mean for the Mérida Agreement? Carolyn Gallaher Historically, Mexico has not figured prominently in US presidential campaigns. The 2016 campaign was an exception. Republican nominee Donald Trump consistently used Mexico and its citizens as metaphors for what ails the US. During the first presidential debate, for example, he described the North American Free Trade Agreement (NAFTA) as "the worst trade deal maybe ever signed anywhere" (Gillespie 2016). Mexican citizens fared no better in Trump's rhetoric. He accused Mexico of dumping its rapists in the US and promised to build a wall to keep them out (Gamboa 2016). Given Trump's relentlessly negative portrayal of Mexico and its citizens, this paper asks what Trump's win might portend for the bilateral Mérida Initiative. I argue that Trump will likely weaken what is positive about the agreement and exacerbate what is negative about it. [End Page 179] A Brief Review of Mérida In 2007, US President George W. Bush and Mexican President Felipe Calderón met in the Yucatan city of Mérida to discuss the problem of narco-trafficking. Eight months later, the Mérida Initiative was officially born. In the joint press release announcing the agreement, the two countries described narco-trafficking, and the solutions to it as a shared responsibility and promised to improve cooperation between their respective law enforcement agencies. The US Congress also pledged up to $1.4 billion in appropriations to get the ball rolling (U.S. Department of State 2008). To assess what the new Trump administration might mean for Mérida going forward, I begin by briefly outlining the initiative's strengths and weaknesses. I focus on one of the agreement's central strengths and one of its foremost weakness. A Needed Thaw The US and Mexico have long had a testy relationship where narco-trafficking is concerned. The low point in the relationship came in 1985 when Enrique "Kiki" Camarena, a Drug Enforcement Agency (DEA) agent stationed in Guadalajara, was murdered. The DEA believed Mexican law enforcement purposely bungled the investigation because Camarena's killers paid them off. By contrast, Mexican officials were angry the DEA was operating in their country and believed Camarena was in over his head (Shannon 1988). For the next thirty years, bilateral cooperation on narco-trafficking was limited and marked by mutual distrust. In this context, the Mérida Initiative represented a major rupture. Mexican government officials had long demanded that the US acknowledge the role of demand in fostering narco-trafficking. As such, when the US announced the agreement by describing the fight against narco-trafficking as a "shared responsibility," Mexicans felt vindicated. Mexican scholar Raùl Benítez Manuat (2009) described Mérida as a paradigm shift in the two countries' relationship. For their part, US officials felt like they could finally engage in cooperation without Mexico labeling their efforts as breaches of sovereignty (Gallaher 2016). Many observers credit the final capture and arrest of Joaquín "El Chapo" Guzmán to the improved cooperation Mérida begat (LaFranchi 2017). In my interviews for a collaborative research project funded by the National Institute of Justice (award number 2011-IJ-CX-0001) on US/Mexican law enforcement cooperation, I also found that better cooperation bled into casework not directly related to narco-trafficking, such as homicide and child kidnapping cases. Complicity For nearly a decade, human rights groups have accused Mexican security forces of violating human rights in their war against narco-traffickers (Amnesty 2015). When the US works with, or funds, units engaging in these violations, it risks becoming complicit in their abuses. Critics of Mérida claim the US has been slow to respond to this moral hazard. Indeed, Mexico has used Mérida money to purchase military equipment, such as Black Hawk helicopters, and to train military and police units—some with known ties to narco-traffickers (Franzblau 2015). They also argue that the US has been reticent to subject [End Page 180] Mexico to the Leahy Laws, which allow the US Departments of Defense and State to withhold foreign aid to countries not abiding by human rights standards (Seelke and Finklea 2017). The George...

Flight Simulation and Control of a Helicopter Undergoing Rotor Span Morphing

This study focuses on the flight simulation and control of a helicopter undergoing rotor span morphing. A model-following dynamic inversion controller with inner and outer loop Control Laws (CLAWS) is implemented, and radius change is introduced as a feedforward component to the inner loop CLAWS. Closed-loop poles associated with the low-frequency aircraft modes are observed to be robust to change in rotor span, eliminating the need for model updates due to span morphing during the dynamic inversion process. The error compensators in the CLAWS use PID control for roll and pitch attitude, PI control for yaw rate and lateral and longitudinal ground speed, but require PII control for vertical speed to avoid altitude loss observed with only PI control, during span morphing. Simulations are based on a span-morphing variant of a UH-60A Black Hawk helicopter at 18,300 lbs gross-weight and 40 kts cruise. From a baseline rotor radius of 26.8 ft, retraction to 22.8 ft, as well as extension to 31.5 ft is considered, nominally over a 60 sec duration. The controller is observed to regulate the longitudinal, lateral and vertical ground speeds well over the duration of the span morphing. Further, the controller is observed to maintain its effectivess in regulating the ground speeds when the span morphing duration is reduced to 30 sec.

Common Black Hawk × Red-shouldered Hawk in California

Common Black Hawk × Red-shouldered Hawk in California

The National Joker: Abraham Lincoln and the Politics of SatireToddNathan Thompson. Carbondale: Southern Illinois University Press, 2015.

The National Joker: Abraham Lincoln and the Politics of Satire Todd Nathan Thompson. Carbondale: Southern Illinois University Press, 2015.Todd Nathan Thompson examines Lincoln's political image. In essence, Lincoln's self-deprecation rendered his critics' satires harmless: his folksy, fallible figure (2) seemed impervious to the kind of caricature that leveled and even destroyed his more pompous contemporary rivals.Thompson distinguishes satire from humor: the former belittles its targets by exaggerating stereotypical behavior or appearance; the latter amuses its audience by exaggerating the foibles of human nature. By poking fun at pompous men, satire effectively undercut the presidential aspirations of Senator Stephen A. Douglas and General George B. McClellan. But by poking fun at a self-confessed frontier rustic, satire ironically helped forward the candidacy of a common man.Lincoln's reputation as a storyteller preceded him. If a political cartoon included the caption, reminds me of a story, readers instantly recognized Lincoln as its speaker. A parabolic storyteller, he was famous for repurposing even apolitical anecdotes for political purposes. For instance, in an Aesop fable, a lion foolishly has his claws and teeth removed at the request of a sly woodsman (father of the girl the lion was courting). When he saw the lion was disarmed, the woodsman easily beat out the lion's brains. Lincoln retold the story to someone advising him that the best way to avoid a civil war was to surrender federal forts in the South. May it not be so, Lincoln said, with me, if I give up all that is asked (13).Lincoln used satiric modesty rhetorically to expose the pretentions of his opponents. For instance, in 1848, when running against a former general who styled himself a war hero, Lincoln would exaggerate his own supposedly unglamorous record in the Black Hawk War. This underdog strategy made the self-proclaimed hero seem a braggart. Later, during the 1858 Lincoln-Douglas debates, six-foot four-inch Lincoln played off the much-touted prominence of his opponent by repeatedly calling five-foot four-inch Douglas a giant, good man. Audiences got the joke. Lincoln was satirizing Douglas's somewhat precious way of describing himself as the little big man.Why didn't the joke backfire on Lincoln? Whereas Douglas was touchy and self-defensive about his shortness, Lincoln made fun of his own awkward height (eight inches taller than the average American). …

This one doesn't count

Corpsmen rushed the severely injured young soldier into casualty receiving of our tent combat support hospital in Kuwait. The army combat medic from the Black Hawk that had delivered this wounded soldier was drenched in sweat, having just performed cardiopulmonary resuscitation (CPR) for 45 minutes in 120°-plus heat. A senior chief corpsman pulled this medic away, telling him, “We have it now.”

Performance Optimization of Variable-Speed and Variable-Geometry Rotor Concept

This paper discusses the application of a particle swarm optimization technique to a rotor dynamics analysis to perform multivariable optimization for minimizing power output for a variable-speed variable-geometry rotor system. A UH-60A Black Hawk helicopter rotor operating at a weight coefficient of is taken as the baseline configuration to study the impact of power reduction through speed and geometry optimization. With the objective of keeping the computational cost low, a rotor dynamics model with the assumption of rigid blades having only flap degree of freedom is developed and coupled to a nonlinear aerodynamic model that has airfoil lookup tables, attached unsteady aerodynamic model and Drees inflow model. The rotor dynamics model is then validated using the flight-test data available in literature. The main rotor power is taken as the fitness function for the particle swarm optimization, and single-variable and multivariable optimizations are carried out to systematically establish the relative significance of various optimization parameters for power minimization. Blade parameters such as radius, chord, trailing-edge plate extension, rotor speed, and blade twist are optimized. For the forward-flight conditions analyzed, the multivariable optimization using all parameters results in a significantly higher power reduction (5.4 to 12.2% more) than that attainable through the optimization by single variables. The rotor speed, radius, and chord (in that order) are the most significant contributors to total power reduction in the multivariable optimization, followed by twist and trailing-edge plate extension.

NDARC을 이용한 헬리콥터 개념설계 및 성능해석 검증 연구

본 연구에서는 단일로터-꼬리로터 형상의 일반 헬리콥터에 대한 개념설계 및 성능해석 기법을 정립하고자 회전익 항공기 개념설계 및 성능해석 코드인 NDARC을 이용하여 UH-60A 헬리콥터에 대한 개념설계 및 성능해석을 수행하였다. 적절히 가정한 임무 형상을 이용하여 UH-60A 헬리콥터의 개념설계를 수행한 뒤 설계 목표 값과의 비교를 통하여 UH-60A 헬리콥터의 형상 및 중량을 적절히 설계할 수 있음을 확인하였다. 더불어, 본 연구로부터 설계된 UH-60A 헬리콥터 모델을 이용하여 다양한 비행 조건에서의 성능해석을 수행한 뒤, 본 연구의 해석 결과를 UH-60A의 성능 시험 및 선행 연구의 해석 결과와 비교하여 본 연구 결과의 타당성을 검증하였다. 그 결과, 단일로터-꼬리로터 형상의 일반 회전익 항공기의 개념설계 및 성능해석 기법을 적절히 정립하였음을 확인하였다. A validation study is conducted for the conceptual design and performance analysis of UH-60A Black Hawk in order to establish the conceptual design and performance analysis techniques for conventional helicopters using a single main rotor and a tail rotor. As a tool for conceptual design and analysis, NDARC(NASA Design and Analysis of Rotorcraft) is used for the present study. The conceptual design for UH-60A is successfully validated as compared with the target values. Then, various performance analyses in hover and forward flight are conducted for the UH-60A model obtained from the present design work, and they are compared well with the wind tunnel test, flight test, and previous analyses using various analysis tools. Through this validation work, the conceptual design and performance analysis techniques for the conventional helicopter are appropriately established.