Airdata calibration of a high-performance aircraft for measuring atmospheric wind profiles

The research airdata system of an instrumented F-104 aircraft has been calibrated to measure winds aloft in support of the space shuttle wind measurement investigation at the National Aeronautics and Space Administration Ames Research Center Dryden Flight Research Facility. For this investigation, wind measurement accuracies comparable to those obtained from Jimsphere balloons were desired. This required an airdata calibration more accurate than needed for most aircraft research programs. The F-104 aircraft was equipped with a research pilot-static noseboom with integral angle-of-attack and flank angle-of-attack vanes and a ring-laser-gyro inertial reference unit. Tower fly-bys and radar acceleration-decelerations were used to calibrate Mach number and total temperature. Angle of attack and angle of sideslip were calibrated with a trajectory reconstruction technique using a multiple-state linear Kalman filter. The F-104 aircraft and instrumentation configuration, flight test maneuvers, data corrections, calibration techniques, and resulting calibrations and data repeatability are presented. Recommendations for future airdata systems on aircraft used to measure winds aloft are also given

Mission-oriented requirements for updating MIL-H-8501. Volume 2: STI background and rationale

A supplement to the structure of a new flying and ground handling qualities specification for military rotorcraft structure is presented in order to explain the background and rationale for the specification structure, the proposed forms of criteria, and the status of the existing data base. Critical gaps in the data base for the new structure are defined, and recommendations are provided for the research required to address the most important of these gaps

Aeronautical engineering: A continuing bibliography with indexes, supplement 100

This bibliography lists 295 reports, articles, and other documents introduced into the NASA Scientific and Technical Information System in August 1978

Development of a simulation tool for flight dynamics and control investigations of articulated vtol unmanned aircraft

A simulation tool for flight dynamics and control investigations of three different Vertical Take Off and Landing (VTOL) unmanned aircraft configurations has been developed. A control concept has been proposed in order to take advantage of the fast response characteristics of the ordinary small engine/propeller propulsion systems in such aircraft, as well as replacing the complex rotors used previously in VTOL concepts for small unmanned aircraft. The simulation model has been established on the basis of the proposed concept so that it can also be used to study the feasibility of this idea. An Object-based methodology has been introduced so as to reduce the amount of aerodynamic required data for the simulation model. The equations of motion associated with the aircraft multibody system with ten degrees of freedom have been derived using the Newton-Euler method. The modelling of various subsystems including the propeller model, the airframe aerodynamics and the engine model has been carried out. A method for calculating the propellers' slipstream effects on the other components has been presented. Input data for the simulation model have been estimated, using different sources. The Advanced Continuous Simulation Language (ACSL) has been used for the programming of the mathematical model. A series of comprehensive tests have been carried out in order to demonstrate the validity of the simulation model. The ability of the simulation model to explain the aircraft modes of motion as well as to discover unknown nonlinear behaviours and to describe them has been demonstrated

Aeronautical Engineering. A continuing bibliography, supplement 115

This bibliography lists 273 reports, articles, and other documents introduced into the NASA scientific and technical information system in October 1979

Combined numerical and experimental simulations of unsteady ship airwakes

Abstract To aid pilot training for shipboard helicopter operations, computational fluid dynamics (CFD) is increasingly being performed to model ship airwakes. The calculated velocity field data are exported to the flight simulator as look-up tables. In the Canadian context, work to expand ship airwake simulation capabilities for future use in flight simulators is currently being done using the open-source OpenFOAM. The current paper reports on the progress of this work using the simple frigate shape 2 (SFS2), which is a highly simplified ship geometry, to validate the method for low-sea-state (also referenced to as static) cases. By employing delayed detached eddy simulations (DDES), OpenFOAM was able to compute the unsteady ship airwakes well compared to experimental data and other references. After validation, OpenFOAM was applied to the Canadian Patrol Frigate (CPF), a more representative example of a naval vessel. Hybrid structured and unstructured grids were used because of the complexity of the CPF geometry. The agreement between the computed and the experimental results for the static CPF was reasonable, which built a solid foundation supporting further development of simulation for the CPF in motion