Aeronautical Engineering Consulting Services

DARcorporation has been offering aeronautical engineering software and consulting services since 1991. Our projects include single and multi-engine propeller and jet powered aircraft, Business Jets, Very Light Jets (VLJ), Kit, LSA and Experimental Category aircraft, VTOL combat force insertion vehicles, VTOL aircraft, UAV's for civil and military applications and hybrid air/ground vehicles.

Experience in the design, detailed analysis and building of prototypes gives DARcorporation a unique advantage over other companies, since we can go from initial design all the way through full size prototype manufacturing. The unique tools we developed for design and analysis make DARcorporation the best choice for any new or existing aeronautical project. DARcorporation engineers can advise on what the best materials are for your design and what the best configuration is. We will work with you to design and optimize your aircraft for performance, manufacturability and cost.

Aircraft Design & Analysis

We can design to LSA, U.S. Experimental Category, U.S. FAR 23, FAR 25, U.S. MIL SPEC requirements. Our projects include single and multi-engine propeller and jet powered aircraft; Business Jets, Very Light Jets (VLJ); Kit, LSA and Experimental Category aircraft; VTOL combat force insertion vehicles; VTOL aircraft; UAV's for civil and military applications and hybrid air/ground vehicles.

We begin every project with a careful review of objectives and existing data and then offer an assessment that includes project cost projection and time line. Our engineers can use your conceptual sketches and specifications to produce a complete design. Or, if you need a review of an existing design, we will analyze your design and provide you a documented projection of performance and cost of your aircraft vehicle and perform a detailed comparative analysis of your competitor's product, including weaknesses and strengths.

Our years of experience, coupled with a practice of doing "trial and error" of airplane designs on our computers, ensures that you will not be surprised by major mistakes on the production floor or in flight testing. Our disciplined approach to designing, analyzing, building and testing airplanes will ensure a successful product.

Aerodynamic Design & Analysis

DARcorporation engineers perform detailed aerodynamic analysis on any structure using our experience and several Computational Fluid Dynamics (CFD) packages. The CFD packages predict fluid flow around objects to analyze aerodynamic characteristics and assist in the optimization of designs. The CFD packages are used to simulate the air flow around aircraft and how the fluid interacts with the aircraft surface for any type of aircraft configuration. Coupled with our Advanced Aircraft Analysis software, the CFD results aid in aerodynamic and stability & control analysis for conventional and unconventional types of aircraft. DARcorporation also utilizes the Quasi-Vortex-Lattice Method, VORSTAB, to analyze both attached and vortex-separated flows to calculate longitudinal and lateral-directional aerodynamic characteristics for various aircraft configurations. Using these CFD packages, we analyze and optimize airfoils to provide the optimal lift, drag, moments and pressure distribution for aircraft lifting surfaces such as, wings, horizontal tails, vertical tails, canards and V-tails. The analytical methods used on wings and other lifting surfaces can be extended to blade analysis for rotors, including propellers, helicopters and wind turbine rotors. Based on Blade Element Momentum (BEM) theory, we further developed and customized our software for initial aerodynamic design of wind turbine blades that can handle any type of configuration (vertical or horizontal axis) and blade shape. Using CFD to simulate rotation, we can quantify the full power curve of the wind turbine. The pressure distribution over the blades is extracted from CFD and torque (and thus energy) curves are constructed. The pressure distributions obtained from the CFD analyses are also used in the structural design and analysis of the blades. Based on the aerodynamic design, a wind tunnel model can be designed, constructed and tested. CFD simulation techniques can also apply to engine inlet design and engine duct flow behavior prediction. Using our own BEM software, we can design propellers/fans to maximize thrust. Over the years, DARcorporation has developed an unique expertise in aerodynamic design of airplanes, wind turbines, fans, inlets and rotors.

Structural Design & Analysis

Finite Element Analysis (FEA), coupled with analytical methods when necessary, is used to carry out multiple types of structural analyses including strength, stiffness, elastic stability, dynamic modes and responses (vibration suppression), fatigue, flutter, crash/impact, etc. Structural analysis software (Femap/Nastran, AFGROW, ZAERO, LS-DYNA, etc.) is used to model and analyze the structure, which can be made of metals (steel, aluminum, etc.), composites (glass, carbon, etc.) or any combination of metals and composites as well as bonded and fastened joints. Pressure distributions, experimental or analytical, are mapped to the structural model to account for the aerodynamic loads. Inertial and thermal loads are also included in the FEA modeling and most load cases are based on LSA, U.S. Experimental Category, FAR 23, FAR 25 and U.S. MIL SPEC requirements. Results such as stresses, deformations, buckling factors, natural frequencies, flutter speeds, impact forces etc. are compared against possible failure modes to ensure the structural integrity. The structural analysis yields selection of materials, material thicknesses, composite layup schedule and produces an optimized structural configuration. Coupled with fatigue analysis, the structural service life is ensured. Detailed 3D CAD models and manufacturing drawings of the structural components can then be generated and used for parts production, assembly and quality control

Structural Review

Upon review of many existing airplane designs, DARcorporation engineers have discovered serious problems with longitudinal and lateral stability of the airplane. Other airplanes had serious stall and spin recovery issues. All of these problems were due to insufficient analysis in the initial design stage. We have also observed structural design, analysis and manufacturing methods that did not meet the rigorous standards demanded by fight vehicles. The outcome was airplanes with serious weight and balance issues and structural defects. All of these problems could have been avoided if adequate engineering had been performed prior to fabrication and if the prototypes were built according to the appropriate flight vehicle standards.

Prototyping & Manufacturing

DARcorporation can design, analyze and build the structure, whether it is made out of composites, metal or a combination of both. We will select materials and provide layup schedules for composites. We will analyze strength, stiffness, elastic stability, flutter and overall system dynamics. DARcorporation engineers have worked with many unconventional designs including experimental airplanes, flying cars and UAVs. Our designs are optimized for best performance based on results from CFD, structural analysis and wind tunnel testing. In addition to designing your vehicle, we will keep us in close involvement in every step of its fabrication and assembly, thereby assuring that "what we designed is what you fly". We can perform static load, dynamic normal modes, flutter and flight tests to ensure that your airplane does what we say it will do.

Wind Tunnel Testing

As part of our aeronautical design and analysis consulting services, DARcorporation performs wind tunnel and water tunnel testing, analysis and management. We have extensive experience with many types and sizes of wind & water tunnel testing programs and have access to the experimental facilities at The University of Kansas, Wichita State University and The University of Washington.

Our team of highly skilled aeronautical engineers can test and analyze models in subsonic and transonic flow regimes. We can conduct flow visualization tests on models and provide qualitative assessments. We will also analyze stability & control and drag data derived from wind tunnel tests. We can test models ranging from 6 inches to 6 feet, using in-house test stands fully integrated with cutting-edge data acquisition systems to collect data in all six degrees of freedom. DARcorporation will plan and manage all aspects of modeling, testing and data analysis. We will provide the perfect liaison with wind tunnel model manufacturing companies and perform model accuracy inspection.

Proposal & Rates

Please Contact Dr. Willem Anemaat for additional information or a detailed proposal. Your detailed proposal will include cost and calendar schedule and estimated man-hours per task. This will be provided at no cost or obligation.