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A high order rotorcraft mathematical model is developed and validated against the XV-15 and a Large Civil Tiltrotor (LCTR) concept. Separate modeling of each rotorcraft component in a multi-body like formulation allows for structural flexibility to be included, which is important when modeling large aircraft where structural modes affect the flight dynamics frequency ranges of interest. Details of the formulation of the mathematical model are given, including derivations of structural, aerodynamic, and inertial loads. Flexibility effects are evaluated by looking at the nature of the couplings between rigid-body modes and wing structural modes and vice versa. A proportional-integral feedback on the structural acceleration is used to improve damping and reduce the overall excitation of a structural mode. A model following control architecture is then implemented on full order flexible LCTR models. The impact of structural feedback investigated. A rigid aircraft model has optimistic performance characteristics, and a control system designed for a rigid aircraft could potentially destabilize a flexible one. The various control systems are flown in a fixed-base simulator. Pilot inputs and aircraft performance are recorded and analyzed., The original document contains color images.

In April 2012 and October 2013, NASA and the U.S. Army jointly conducted a wind tunnel test program examining two notional large tilt rotor designs: NASA s Large Civil Tilt Rotor and the Army s High Efficiency Tilt Rotor. The approximately 6%-scale airframe models (unpowered) were tested without rotors in the U.S. Army 7- by 10-foot wind tunnel at NASA Ames Research Center. Measurements of all six forces and moments acting on the airframe were taken using the wind tunnel scale system. In addition to force and moment measurements, flow visualization using tufts, infrared thermography and oil flow were used to identify flow trajectories, boundary layer transition and areas of flow separation. The purpose of this test was to collect data for the validation of computational fluid dynamics tools, for the development of flight dynamics simulation models, and to validate performance predictions made during conceptual design. This paper focuses on the results for the Large Civil Tilt Rotor model in an airplane mode configuration up to 200 knots of wind tunnel speed. Results are presented with the full airframe model with various wing tip and nacelle configurations, and for a wing-only case also with various wing tip and nacelle configurations. Key results show that the addition of a wing extension outboard of the nacelles produces a significant increase in the lift-to-drag ratio, and interestingly decreases the drag compared to the case where the wing extension is not present. The drag decrease is likely due to complex aerodynamic interactions between the nacelle and wing extension that results in a significant drag benefit., Presented at the Fifth Decennial AHS Aeromechanics Specialists'Conference held in San Francisco, CA on 22-24 Jan 2014. Prepared in collaboration with the Aeromechanics Office NASA Ames Research Center, Moffett Field, CA, and Monterey Technologies, Inc., NASA Ames Research Center, Moffett Field, CA.

Wind or rotorwash generated by rotors, ducts, or jets effect the operational suitability and utility of future Vertical Takeoff and Landing (VTOL) aircraft. As the aircraft s physical size, weight, and disk loading increases beyond the range of current systems, the risk increases that rotorwash operational impact(s) may compromise an aircraft s ability to satisfy the Warfighter's needs. Early definition of anticipated rotorwash conditions will permit an assessment of operational suitability and determine whether specific design changes are warranted and/or if acceptable operational tactics, techniques, and procedures can be established. This report documents the assessment process, environmental limits, rotorwash modeling, and output display supporting the rotorwash operational footprint model. These elements graphically combine to display the rotorwash operational impact assessment on the ground environment as contour plots or footprints. The tools developed are for the single main rotor helicopter, tandem helicopter, and tiltrotor configurations, but they can be extended to encompass additional configurations. The rotorwash operational footprint displays the effect of winds generated by rotor thrust on the surrounding environment. These footprints can be used to evaluate compliance with aircraft performance specifications, verify safe separation distances, or inform design trade studies., Prepared in collaboration with U.S. Army RDECOM Forward Element Command-Atlantic and Aviation and Missile Research, Development, and Engineering Center, Ruislip, United Kingdom; Naval Air Systems Command, Patuxent River, MD; and EMA, Mansfield, TX. The original document contains color images.

The V-22 Osprey Joint Services Advanced Vertical Lift Aircraft (V-22) Program is charged by the DoD with developing, testing, evaluating, procuring, fielding and supporting a tilt rotor, Vertical/Short Takeoff and Landing (V/STOL) aircraft for Joint Service application. The Navy was designated the Executive Agent with support from the United States Air Force (USAF) in the V-22 Joint Program Office located at the Naval Air Systems Command Headquarters, Naval Air Station Patuxent River, MD. The V-22 Program is designed to provide an aircraft to meet the amphibious/vertical assault needs of the United States Marine Corps (USMC), the strike rescue needs of the Navy, and the special operations needs of the USAF and United States Special Operations Command (USSOCOM). The MV-22 variant is replacing the CH-46E in the USMC and will supplement the H-60 in the Navy. The CV-22 variant provides a new capability and augments the MC-130 in the USAF/USSOCOM inventory for special operations infiltration, exfiltration, and resupply missions. The V-22 is capable of flying over 2,100 nautical miles with a single refueling, giving the Services the advantage of a V/STOL aircraft able to rapidly self-deploy to any location in the world. Block Descriptions: V-22 capability is being increased and fielded over time via a Block upgrade acquisition strategy. MV-22 Block A provides a Safe and Operational Test and Training Asset configuration that supports developmental and operational flight tests, as well as fleet training. MV-22 Block B provides for correction of previously identified deficiencies and suitability improvements. MV-22 Block C provides mission enhancements, primarily in the areas of environmental control systems upgrades and mission systems improvements. Block 0/10 is a CV-unique configuration including radar and electronic countermeasures upgrades. Block 20 will provide an enhanced CV-unique configuration with communications and aircraft system performance upgrades., Selected Acquisition Report-SAR. The original document contains color images.

The MQ-8 Vertical Takeoff and Landing Tactical Unmanned Aerial Vehicle Fire Scout (VTUAV) program supports the Close Range Reconnaissance, Surveillance and Target Acquisition Capability Mission Need Statement, and the Capability Production Document for the VTUAV System, as ammended May 15, 2009. Additionally, the performance attributes of the MQ-8 support the Littoral Combat Ship, the Vertical Unmanned Air Vehicle (UAV), the Assured Maritime Access in the Littorals, the Joint Strike Enable and the Penetrating Intelligence, Surveillance, and Reconnaissance for Area Denial Threat Environments Initial Capabilities Documents. An MQ-8 system is composed of air vehicles, Electro Optic/Infrared/Laser Designator Range Finder payload (one per air vehicle), Ground Control Station (GCS), Tactical Control System software, Tactical Common Data Link, UAV Common Automatic Recovery System for automatic take-offs and landings, and associated spares and support equipment. The MQ-8 launches and recovers vertically and can operate from all air capable ships as well as confined area land bases. Other characteristics include autonomous waypoint navigation with command override capability, a heavy fuel engine, and the ability to incorporate future mission packages. Each GCS will perform mission planning, air vehicle and mission payload control, receive incoming payload data and distribute the data to existing shipboard Command, Control, Communication, and Computer Information systems., Selected Acquisition Report-SAR. The original document contains color images.

The F-35 Joint Strike Fighter Aircraft (F-35) Program will develop and field an affordable, highly common family of next-generation strike aircraft for the United States (U.S.) Navy, Air Force, Marine Corps, and allies. The three variants are the F-35A; F-35B; and the F-35C. The F-35A will be a stealthy multi-role aircraft, primarily air-to-ground, for the Air Force to replace the F-16 and A-10 and complement the F-22. The F-35B variant will be a multi-role strike fighter aircraft to replace the AV-8B and F/A-18A/C/D for the Marine Corps. The F-35C will provide the U.S. Navy a multi-role, stealthy strike fighter aircraft to complement the F/A-18E/F. The planned DoD F-35 Fleet will replace the joint services' legacy fleets. The transition from multiple type/model/series to a common platform will result in a smaller total force over time and operational and overall cost efficiencies., Selected Acquisition Report-SAR. The original document contains color images.

The introduction of the F-35B provides the USMC an opportunity to rexamine the requirements and redefine the capabilities of the fixed wing component of the Aviation Combat Element (ACE) within the Marine Expeditionary Unit (MEU). The current six-plane detachment provided by the AV-8B maintains several shortfalls within the overall operating philosophy of USMC aviation. The F-35B now expands the mission set across all six functions of Marine Corps Aviation. The expectations of additional mission requirements, expectation to operate in A2AD environments, increased avionics will require a greater sortie generation capability than currently provided by the six (6) AV-8Bs. This paper analyzes the current shortfalls inherent in the current six-plane model and proposes one possible solution consisting of eight (8) F- 35Bs. This solution generates capability options in line with current and expected sortie generation requirements as well as possible future operating concepts in distributed operations.

The span of PACOM's Area of Responsibility (AOR) combined with the current Administration's focus in the Western Pacific provide numerous challenges to rapidly deploy within the operational reach of the MAGTF Commander. The prompt response to today's requirements in the Western Pacific is critical to the MAGTF's self-sufficiency as well as promoting the PACOM Commander's Intent of Theater Security Cooperation and humanitarian assistance. More specifically, how should the MAGTF deploy personnel and equipment throughout the PACOM AOR without the sole reliance on a single KC-130 squadron? This MMS concept is to examine the roles of WestPac KC-130 mission essential tasks, employment, and current structure with the responsibilities and force laydown of Marine Corps Operational Support Airlift (OSA) in order to provide higher echelon commands with solutions to increasing lift demands while maintaining the combat effectiveness of the KC-130 squadron. In addition, this MMS topic will focus on concurrent utilization, funding and additional procurement of aviation equipment and command and control of lift assets. This proposal will provide commanders with an overview of lift capabilities as well as proposed solutions for assets and force structure laydown in order to maintain the cost effective and efficient autonomy and survival of the MAGTF.

The effect that defense reform has had on the procurement of major weapon systems is a topic that will often be debated as the Department of Defense and the military services transform to meet the needs for the uncertainties of the 21st century and beyond. For this reason, a study of the evolution of defense budgeting and acquisition and the significant pieces of legislation that shaped the way we acquire major weapon systems provides insight into our current structure and effectiveness of federal budgeting and acquisition process. Presented in this thesis are the effects that the Goldwater-Nichols Department of Defense Reorganization Act of 1986 (GNA) had on the procurement of the V-22. This study provides a detailed look at factors that led up to the enactment of GNA. It will also examine acquisition shortcomings that led to the passing of the legislation and budget shortfalls in the 1980s that carried over to the early 1990s. This thesis, in particular, studies the early days of the Vertical Takeoff and Landing (VTOL) technology and the research and development advancements up to the development of the V-22. It also assesses the characteristics of the V-22 design and its ability to influence combat technology. This thesis assesses the impact and implications that the legislation had on the V-22 as a major weapons system. The thesis concludes that recommendations of the GNA were not adopted and, therefore, not properly implemented and that the GNA had little to no effect on acquisition and production of the V-22.

This study determined the optimum number of blades on a 4-inch diameter cross-flow fan rotor such that the rotor produced a thrust-to-weight ratio over one, which will make vertical take-off possible. The commercial computational fluid dynamics software ANSYS CFX, along with the commercial computer-aided design software SolidWorks, was used to model and perform a parametric study on the number of rotor blades. This parametric study focused on the thrust output, power requirement, and efficiency of each design in order to determine the optimum number of blades at 8,000 RPM. After the analytical study was complete, working models of three different rotors were fabricated and tested to validate the results found using ANSYS CFX. The experimental and analytical models were successfully compared at speeds ranging from 4,000 to 7,000 RPM.

The research presented is dedicated to determining an efficient rotor and housing system that will generate a sufficient thrust-to-weight ratio for vertical take-off and landing through computational modeling, implementation and experimentation. To accomplish this task, a new 20-bladed rotor was designed in SolidWorks and imported into ANSYS-CFX, which was used to analytically determine the thrust generated at speeds ranging from 4,000 rpm to 10,000 rpm. Upon successful simulation, a carbon-fiber model was fabricated and tested at speeds from 4,000 rpm to 9,700 rpm. With a promising thrust-to-weight ratio, a platform was built for initial testing utilizing two motors and four cross-flow fans. Initial platform testing was successful and generated sufficient thrust for vertical take-off.

The introduction of MV-22Bs and F-35Bs to the Aviation Combat Element (ACE) increases the aviation logistics footprint aboard ship and limits operational employment options by decreasing sortie generation rates and encroaching on the space available to conduct operational missions. Simply decreasing the number of aircraft assigned to the MEU will only serve to decrease sortie generation capability for the sake of space. Modifications to the ACE embarkation plans, aircraft support equipment, and aircraft maintenance capabilities aboard the LPD-17 class ship are required to increase sustainability for aviation assets during shipboard operations.

Considering the capabilities of existing simulators, the training models of the commercial aviation industry and KC-130J community, and available scientific research, creating a MV-22 training model that reduces or eliminates the requirement for a FRS is a realistic goal. In the face of looming budget cuts, the Marine Corps must find efficiencies to reduce costs while preserving current capability. Just in MV-22 flight hour costs alone, capitalizing on existing simulator technologies and proven training models could yield in excess of $200 million in savings over a 10-year period. To achieve this, the Marine Corps must mandate change and leverage the training models of the commercial aviation industry and the KC-130J community.

If properly selected, low-cost commercially available off-the-shelf light- and medium-fixed-wing aircraft are sufficient to effectively accomplish special operations aviation mission sets in support of special operations ground forces. As the nature of combat continues to shift away from traditional state-on-state wars to more irregular conflicts, the skills possessed by special operations forces (SOF) will become key to a nation's success in achieving its national security aims. While numerous allied nations possess skilled and ready ground SOF components, relatively few possess special operations aviation capabilities. This lack is largely due to the prohibitively high costs of acquiring and maintaining such specialized niche aircraft. This study employs a qualitative analysis of candidate aircraft that examines acquisition costs, cost per flying hour, aircraft performance specifications, and aircraft capabilities, and scores each aircraft against a list of hallmark qualities of SOF aviation to assess candidate aircraft utility. The evaluation determined that all four light-fixed-wing and all three medium-fixed-wing candidate aircraft are fine choices for executing SOF support. The Britten-Norman BN2T-4S Defender outscored all of the other candidates, possessing the most hallmark qualities. However, the Pilatus PC-6 Porter was the most economically efficient light-fixed-wing platform, costing $2M less than the Defender over a typical aircraft lifespan. In the medium-fixed-wing category, the Alenia Aermacchi C-27J is the clear standout in overall performance and utility. Although these recommendations are meant to help SOF leadership make a sound decision, overall aircraft preference should be based on the aircraft capabilities a nation's SOF value most, given its specified budget.

Vertical Take-Off and Landing (VTOL) has primarily seen research and development in the two traditional fields, namely the rotary wing and jet propulsion, with each seeking incremental improvements in thrust generation and fuel efficiency, respectively. In recent years, there has been increasing interest in the viability of the Cross-Flow Fans (CFF) being the primary source of aircraft propulsion. There has been measured success in horizontal flight; however, VTOL propulsion with CFFs remains elusive. The current study seeks to determine the feasibility of combining two CFFs in a back-to-back configuration that could augment the thrust generated, thus making VTOL a reality. Making use of an optimized CFF housing, the research aimed to maximize the thrust generated in the above mentioned configuration by varying the gap between the CFFs. Computational fluid simulations of the dual CFF configuration was performed using ANSYS CFX to find the thrust generated as well as the optimal operating point. Analysis was done at three different speeds (3,000 rpm, 5,000 rpm and 8,000 rpm) and four different distances between the dual CFFs (26 mm, 52 mm, 78 mm and 104 mm). Thereafter, an experiment was conducted to compare and validate the results of the simulation.

The cross-flow fan (CFF) is a lifting and propulsion device that retains the advantages of a fixed-wing aircraft by using a ducted lift fan. There is no upper limit to the rotor length-to-diameter ratio of a CFF, allowing the device to be installed along the length of the wing or lifting device. The CFF discharged vector can be easily rotated about the fan axis since the fan has no angular requirements, further allowing the capability of vertical take-off and landing (VTOL) by thrust vectoring. CFF possess the potential to propel an airframe to flight; however, adequate thrust must be produced by the CFF for it to realize VTOL. Conventional CFF designs with straight blades produce unacceptable noise levels for personal air vehicle operation. It is believed that helical blades could solve the sound pressure-level problem and produce more thrust to aid VTOL. Using computational fluid dynamics (CFD) software, ANSYS-CFX, a three-dimensional (3-D) straight-bladed model was validated against a previous study's experimental results. A 3-D model with helical blades was constructed to investigate the performance. The analytical results have shown that helical blades could increase the thrust performance of a CFF, and could possibly realize VTOL.

Reinforce deploying Carrier Strike Groups (CSGs) with a crisis response force package (a Marine Expeditionary Element, or MEE) composed of a Marine Weapons Platoon and a four ship detachment of V-22 Ospreys. This force package significantly improves the Navy's existing Tactical Recovery of Aircraft and Personnel (TRAP), Special Operations Forces (SOF) support, Humanitarian Assistance Disaster Relief (HA/DR), Security Cooperation and Forward Engagement capability, and adds Raid, Vertical Board Search and Seizure (VBSS) and Non-Combatant Evacuation Operations (NEO) capability. The MEE could operate independently or form the foundation for an expanded SOF unit. SOF personnel could be already embarked or sent to rendezvous with the MEE on short notice to accomplish a specific mission. The force packages pre-deployment workup training would be balanced between shipboard operations and training with designated USSOCOM units in order to establish a baseline capability of mission essential tasks. The end state is a modular expeditionary unit in support of a CSG, providing SOF mobility and supporting fire power tailored to the operational commander's needs.

The Large Civil Tiltrotor (LCTR) was developed as part of the NASA Heavy Lift Rotorcraft Systems Investigation in order to establish a consistent basis for evaluating the benefits of advanced technology for large tiltrotors. The concept has since evolved into the second-generation LCTR2, designed to carry 90 passengers for 1,000 nm at 300 knots, with vertical takeoff and landing. This paper examines the impact of advanced propulsion system concepts on LCTR2 sizing. Two concepts were studied: an advanced, single-speed engine with a conventional power turbine layout (Advanced Conventional Engine, or ACE), and a variable-speed power turbine engine (VSPT). The ACE is the lighter engine, but requires a multi-speed (shifting) gearbox, whereas the VSPT uses a lighter, fixed-ratio gearbox. The NASA Design and Analysis of Rotorcraft (NDARC) design code was used to study the trades between rotor and engine efficiency and weight. Rotor performance was determined by Comprehensive Analytical Model of Rotorcraft Aerodynamics and Dynamics (CAMRAD II), and engine performance was estimated with the Numerical Propulsion System Simulation (NPSS). Design trades for the ACE vs. VSPT are presented in terms of vehicle weight empty for variations in mission altitude and range; the effect of different One Engine Inoperative (OEI) criteria are also examined. Because of its strong effect on gearbox weight and on both rotor and engine efficiency, rotor speed was chosen as the reference design variable for comparing design trades. The two propulsion concepts had nearly identical vehicle weights and mission fuel consumption, and their relative advantages varied little with cruise altitude, mission range, or OEI criteria; high cruise altitude and low cruise tip speed were beneficial for both concepts., Presented at the American Helicopter Society Future Vertical Lift Aircraft Design Conference, San Francisco, CA, January 18-20, 2012.

A Translational Rate Command (TRC) control law has been developed to enable low speed maneuvering of a large civil tiltrotor with minimal pitch changes by means of automatic nacelle angle deflections for longitudinal velocity control. The nacelle actuator bandwidth required to achieve Level 1 handling qualities in hover and the feasibility of additional longitudinal cyclic control to augment low bandwidth nacelle actuation were investigated. A frequency-domain handling qualities criterion characterizing TRC response in terms of bandwidth and phase delay was proposed and validated against a piloted simulation conducted on the NASA-Ames Vertical Motion Simulator. Seven experimental test pilots completed evaluations in the ADS-33E-PRF Hover Mission Task Element (MTE) for a matrix of nacelle actuator bandwidths, equivalent rise times and control response sensitivities, and longitudinal cyclic control allocations. Evaluated against this task, longitudinal phase delay shows the Level 1 boundary is around 0.4-0.5 s. Accordingly, Level 1 handling qualities were achieved either with a nacelle actuator bandwidth greater than 4 rad/s, or by employing longitudinal cyclic control to augment low bandwidth nacelle actuation.

The present study is focused on determining a housing design that, when paired with an off-the-shelf cross-flow fan rotor, will generate a trust-to-weight ratio significant enough to allow for vertical take-off. The commercial computational fluid dynamics software, ANSYS CFX, was used to perform a computational analysis of various housing designs until a suitable design was identified to construct for experimentation. Following the analytical phase, the conceptual housing was fabricated and paired with an appropriate rotor to validate the predicted performance. The experimental model was operated at speeds from 4,000 to 8,000 rpm and the actual and projected thrust calculations were found to agree with a maximum difference of less than 7%., The original document contains color images. Sponsored inpart by National University of Singapore, Singapore.

The V-22 Osprey is the world's first production tiltrotor aircraft. Unlike any aircraft before it, the V-22 successfully blends the vertical flight capabilities of helicopters with the speed, range, altitude, and endurance of fixed-wing transports. This unique combination provides an unprecedented advantage to warfighters, allowing current missions to be executed more effectively, and new missions to be accomplished that were previously unachievable on legacy platforms. Comprehensively tested and in full rate production, the V-22 provides strategic agility, operational reach, and tactical flexibility - all in one survivable, transformational platform. Mission and Description: The V-22 Osprey Program is charged by the Department of Defense (DoD) with developing, testing, evaluating, procuring and fielding a tiltrotor Vertical/Short Takeoff and Landing (V/STOL) aircraft for Joint Service application with the Navy being the lead. The V-22 program is designed to provide an aircraft to meet the amphibious/vertical assault needs of the United States Marine Corps (USMC), the strike rescue needs of the Navy, and the special operations needs of the United States Special Operations Command (USSOCOM). The MV- 22B variant is replacing the CH-46E. The CV-22 variant provides a new capability and will augment the MC-130 in the USAF/USSOCOM inventory for special operations infiltration, exfiltration, and resupply missions.

Presented at the NASA Fundamental Aeronautics Program 2011 Technical Conference, held in Cleveland, OH, on March 15-17, 2011.

The U.S. Marine Corps has much at stake with the F-35B Short Takeoff and Landing (STOVL) version of the Joint Strike Fighter. In a strategic gamble, the Corps has shaped an amphibious force around the technology and capabilities promised by this program. To support the nation's expeditionary force in readiness, the conceptual capabilities of this platform will continue to provide a unique and powerful piece of the Marine Air Ground Task Force (MAGTF). Facing an uncertain future, the Marine Corps continuously defends its fixed-wing strike/fighter programs within the Naval Aviation community and the Department of Defense. Little has been published on alternatives to this aircraft. This SRP analyzes the capabilities of STOVL, recommends a future course of action, and champions the use of a Vertical Unmanned Aerial System to enhance the MAGTF., Strategy Research Project.

This article summarizes the capabilities and development of the Helios version 2.0, or Shasta, software for rotary wing simulations. Specific capabilities enabled by Shasta include off-body adaptive mesh refinement and the ability to handle multiple interacting rotorcraft components such as the fuselage, rotors, flaps and stores. In addition, a new run-mode to handle maneuvering flight has been added. Fundamental changes of the Helios interfaces have been introduced to streamline the integration of these capabilities. Various modifications have also been carried out in the underlying modules for near-body solution, off-body solution, domain connectivity, rotor fluid structure interface and comprehensive analysis to accommodate these interfaces and to enhance operational robustness and efficiency. Results are presented to demonstrate the mesh adaptation features of the software for the NACA0015 wing, TRAM rotor in hover and the UH-60A in forward flight., Presented at AIAA Aerospace Sciences Meeting (49th) including the New Horizons Forum and Aerospace Exposition, Orlando, Florida, Jan. 4-7, 2011 and published as AIAA-2011-1105. The original document contains color images.

Mission studies have shown strong potential to reduce in-theater casualties by using high-speed rotorcraft capable of both vertical takeoff and landing (VTOL) and high-speed, high-altitude, long-range cruising. The rotational speed of the prop-rotors on this type of vehicle must be slowed during forward flight to maintain high propulsive efficiency. One approach to meeting this requirement is to use a variable-speed power turbine (VSPT) to drive the prop-rotor. However, power turbines run most efficiently at high-speed and within a narrow speed range. The research and technology development effort described herein was funded by the U.S. Army Research Laboratory's (ARL) Director's Research Initiative award to develop the technology foundation needed for power turbines that operate efficiently over a speed range that may vary by as much as 50%. Results from this technology development effort are reported. Major barriers to VSPT operation and the approach selected for VSPT design are discussed. Results from the computational analysis and design system that has been assembled and validated are presented along with preliminary designs for VSPT incidence-tolerant blade sections. Technology transfer and future plans and collaborations, including performance evaluation using a turbine cascade and test rig or engine evaluations, are also discussed., The original document contains color images.

The all STOVL force provides economy 6f scale by combining the logistical requirements of three different aircraft into one. Instead of three aircraft for the price of one, however, the Marine Corps is getting one aircraft for the price of three. The all STOVL force is a tactical and economical mistake. The Marine Corps is a niche force that requires niche aircraft to prosecute the mission. Trying to make one STOVL aircraft fill the roles of three different communities will result in a degraded product for the Marines on the ground. The Marine Corps needs the F-35B, but it also needs a diverse air arm capable of efficiently fighting the full spectrum of future conflicts.

AGENDA: Current Initiatives/Programs * The Aviation Science and Technology Challenge * OSD Future Vertical Lift * Transition to the Future. Current Initiatives Shaping the Future * US Army Aviation Center of Excellence (USAACE) Aviation Operations Capability Based Assessment (CBA) * USAACE Joint Multi-Role (JMR) Aircraft Analysis Study * DARPA/Army Study on the Future of VTOL Aviation * OSD Future Vertical Lift Initiative * Army Aviation JMR Demonstrator Program., Document consists entirely of briefing charts.

Coupling of aeromechanics analysis with vehicle sizing is demonstrated with the CAMRAD II aeromechanics code and NDARC sizing code. The example is optimization of cruise tip speed with rotor/wing interference for the Large Civil Tiltrotor (LCTR2) concept design. Free-wake models were used for both rotors and the wing. This report is part of a NASA effort to develop an integrated analytical capability combining rotorcraft aeromechanics, structures, propulsion, mission analysis, and vehicle sizing. The present paper extends previous efforts by including rotor/wing interference explicitly in the rotor performance optimization and implicitly in the sizing., Presented at the American Helicopter Society Aeromechanics Specialist's Conference, San Francisco, CA, 20-22 Jan 2010.

We present a method of performing precision landings of a vertical take-off and landing (VTOL) unmanned air vehicle (UAV) with the use of an onboard vision sensor and information about the aircraft's orientation and altitude above ground level (AGL). A method for calculating the 3-dimensional location of the UAV relative to a ground target of interest is presented as well as a navigational controller to position the UAV above the target. A method is also presented to prevent the UAV from moving in a way that will cause the ground target of interest to go out of view of the UAV's onboard camera. These methods are tested in simulation and in hardware and resulting data is shown. Hardware flight testing yielded an average position estimation error of 22 centimeters. The method presented is capable of performing precision landings of VTOL UAV's with submeter accuracy.

Validation results are discussed and compared in confirming the tendency of certain parameters being well represented by simulation with the actual at-sea result. The primary objective of this field of study is to determine the feasibility of applying full motion simulators and plug and play simulations in support of dynamic interface at-sea testing and experimentation. Several years of simulated flight test programs using the Merlin CAE Trainer System at RNAS Culdrose (UK) and the Manned Flight Simulator at Naval Air System Command, Aircraft Division at Patuxent River, Maryland have been conducted. A typical simulation consists of modular "plug and play" components contributed by the project participants assembled in a High Level Architecture (HLA) with the combined components reflecting the ship environment, the long and short term prediction methodologies and the ship's response mechanism. The use of 6 degree-of-freedom motion flight simulator to forecast physical deck motion and deck motion limits, is discussed. In the manned version, the simulated flight test has several objectives including assess the capabilities of the Cockpit Dynamic Simulator (CDS) to support Ship-Helicopter Operational Limit (SHOL) / Naval Air Training and Operating Procedures Standardization (NATOPS) limits demonstrate High Level Architecture (HLA) with selected modules; and determine feasibility of applying these simulators in support of dynamic interface at-sea testing. The unmanned and manned systems studied focused on specific simulated aircraft-ship interface responses. An application of this simulation is the forecast of deck limits computed by the motion characterization of a platform in terms of, and as a function of, the deflection of landing gear configured for vertical landing aircraft or rolling vertical landing., Presented at the American Society of Naval Engineers Launch and Recovery Symposium, entitled "Launch, Recovery and Operations of Manned and Unmanned Vehicles from Marine Platforms," held in Arlington, VA, on 8-9 December 2010. The original document contains color images.

The cross-flow fan has an inherent ability to provide thrust to an airfoil as well as provide boundary layer control. The thrust can be easily vectored and usually the cross-flow fan is fully embedded within the airfoil, making its operation relatively safe. Those characteristics make it very favorable as a propulsive means for a vertical takeoff and landing (VTOL) aircraft. However, further design improvements are needed for competitive comparison with existing conventional aircraft propulsion methods. The baseline configuration was scaled from a 12-inch diameter, 30-bladed rotor developed by Vought Systems in the 1970s to a 6-inch rotor as a more realistic size for integration into a propulsive wing. Using the computational fluid dynamics (CFD) software, ANSYS CFX, previous baseline configuration models were validated at full-speed range to verify the software's prediction. Then, a model with the cross-flow fan embedded at the trailing edge was built and different configurations were examined. An attempt was made to improve the performance of the cross-flow fan embedded airfoil by thrust and thrust-to-power ratio, and lift and drag forces were calculated. CFD results have shown that a rotor with fewer blades can improve performance and a 22-bladed rotor was selected and examined experimentally. Results were compared with the baseline 30-bladed rotor., The original document contains color images.

Our vision for the Army Aviation Technology Center of Excellence (ATCoeE) is that of an organization, based at Redstone Arsenal with global reach, that will implement mechanisms for matching research, development, technology, and testing needs to research, development, technology, and testing solutions that focus on the warfighter's current needs and orienting the next generation of aviation research, development, technology, and testing to the Army's future requirements/threats. Our mission is to establish an aviation land based vertical lift and unmanned air systems Research, Development, Acquisition, Test, Evaluation and Sustainment (RDATES) Center of Excellence to assist all partners in meeting their unit/agency present and future missions through collaboration, sharing, teaming and partnering., The original document contains color images. All DTIC reproductions will be in black and white.

In November 2008, a flight of four CV-22 Ospreys, along with corresponding maintenance/ logistics support, deployed to Bamako, Mali, in Africa to participate in Flintlock-the premier exercise to support future training and engagement in the Trans-Saharan region. Not only was this exercise significant in the fact that it was the first time U.S. Air Force Special Operations Command (AFSOC) CV-22 aircraft had deployed across the Atlantic Ocean to support special operations forces (SOF), but its importance lay in the achievement of combatant commander objectives: assisting partner nations in establishing and developing military interoperability and strengthening regional relationships in support of future combined humanitarian, peacekeeping, and disaster relief operations. While in Mali, Malian and U.S. military personnel conducted Medical Civic Action Programs and Veterinary Civic Action Programs aimed at providing select medical and veterinary services to rural communities in Mali. This story provides only one example of how AFSOC continues expanding our capabilities to provide the combatant commander with the full spectrum of specialized airpower. Providing airlift for access to rural populations represents a paradigm shift in thinking about how SOF airpower is applied to meet the commander's objectives. The context of irregular warfare is expanding perceptions of the term the art of the possible., Pub. in Joint Force Quarterly (JFQ), n56 p80-84, 1st quarter 2010.

A conceptual design tool was built to explore power requirements of a hybrid-power system for Micro Air Vehicles (MAVs) comparable in size to the Cooper's Hawk. An inviscid aerodynamic code, Athena Vortex Lattice (AVL), and a motor-propeller analysis code, QPROP, provide overall lift, drag, and thrust data for power-required calculation as functions of many variables to include mass, platform geometry, altitude, velocity, and mission duration. Phoenix Technologies? Model Center was used to integrate multi-disciplinary components that employ specific power and specific energy of two power sources to determine power system mass required for a designated mission. The tool simulated a mission for the fixed wing Generic Micro Aerial Vehicle (GenMAV), and relative sizing between a high specific power source and a high specific energy source was investigated. Current small fuel cell technology provides inadequate specific power. It was found that a MAV-sized fuel cell-battery hybrid-power system would not perform better than a pure battery or battery-battery power system. A feasible fuel cell capability requirement of at least 325 W/kg matched with at least 921 W-hr/kg was identified as a fuel cell - Li-Po solution for a defined 30 min mission resulting in reduced power system mass compared to using only Li-Po batteries., The original document contains color images.

The V-22 is a technological leap in rotary wing performance characteristics and far exceeds the capabilities of the CH-46E, but due to issues with protection, capabilities, and cost it cannot safely fill the gap the United States Marine Corps needs filled in assault support. Soon after the XV-15 was in a flight demonstration at the Paris Air Show in 1981, the Department of Defense started the Joint Service Advanced Vertical Lift Aircraft (JVX) program to investigate the use of tilt-rotor technology to replace the then current medium-lift tactical transport aircraft in the military. From that point on, the V-22 program has gone through many controversial debates and decisions. But one thing that has not been given enough thought is the change in the threat environment, the vast proliferation of these threats, and the increasing involvement of nonstate actors. The tactics and operating parameters of Marines in the field have changed in the decades since the V-22 was conceived. These changes have affected the current and future threats the V-22 will encounter. The United States Marine Corps should take a serious look at two areas of interest. First, the protection of the V-22 is in jeopardy if changes in self-protection and escort capabilities are not made. Second, there is a need for another medium/heavy lift rotary wing assault support aircraft to fill the capabilities gap between the CH-53K and the V-22 in both cost and aircraft efficiency.

The V-22 Osprey is a tilt-rotor aircraft that takes off and lands vertically like a helicopter and flies forward like an airplane. Department of Defense (DoD) plans call for procuring a total of 458 V-22s: 360 MV-22s for the Marine Corps; 50 CV-22 special operations variants for U.S. Special Operations Command (USSOCOM) (funded jointly by the Air Force and USSOCOM); and 48 HV-22s for the Navy. Through FY2009, a total of 181 V-22s have been procured -- 155 MV-22s for the Marine Corps, and 26 CV-22s for USSOCOM. These totals include several V-22s that have been procured in recent years through supplemental appropriations bills. V-22s are currently being procured under a $10.4 billion, multiyear procurement (MYP) arrangement covering the period FY2008-FY2012. The MYP contract, which was awarded on March 28, 2008, covers the procurement of 167 aircraft -- 141 MV-22s and 26 CV-22s. The proposed FY2010 budget requested funding for the procurement of 30 MV-22s and 5 CV-22s. The budget requested about $2.3 billion in procurement and advance procurement funding for procurement of MV-22s, and about $565 million in procurement and advance procurement funding for procurement of CV-22s. For FY2010, the V-22 program poses a number of potential oversight issues for Congress, including the aircraft's reliability and maintainability. A June 23, 2009, hearing before the House Oversight and Government Reform Committee reviewed a number of issues concerning the V-22 program, including the aircraft's reliability and maintainability., CRS Report for Congress.

The MV-22 Osprey brings new challenges and possibilities to Marine Corps aviation operations. Because of its unique capabilities, the Osprey has the possibility to develop into a versatile, utility-type role with an expanded mission-essential task list, rather than serving solely as the new medium lift assault support platform. However, the escort role must be addressed in order to better employ the Osprey as an assault support platform. It is up to assault support planners, weapons and tactics instructors (WTI's), and innovative aviators to further develop tactics, techniques, and procedures that will maximize the capabilities of this aircraft while fully integrating it into Marine Corps aviation operations.