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A spin-tunnel investigation of the spin and recovery characteristics of a 1/25-scale model to the General Dynamics F-16XL aircraft was conducted in the Langley Spin Tunnel. Tests included erect and inverted spins at various symmetric and asymmetric loading conditions. The required size of an emergency spin-recovery parachute was determined.
A method for approximating the vacuum motions of spinning rigid symmetrical bodies with varying spin rates and inertias has been completed. The analysis includes the effects of time varying thrust misalignments, mass unbalance, and jet damping. Results are given in the form of equations for space referenced Euler angles, flight-path angles, body referenced attitude rates, and earth-referenced vehicle-trajectory coordinates. The method consists of dividing the problem into intervals during which the time-dependent variables are assumed constant at their mean interval value. In order to check this procedure, solutions for various interval sizes are compared with solutions obtained with numerical methods. Although the method is somewhat lengthy for accurate hand computation in most cases, it is readily programed for machine solutions. Probably more important, the general solutions give insight into the separate effects of the variables and, in many cases, can be quickly used to determine the approximate ranges of the variables required for the desired solution to a given problem. In this respect, equations for determining maximum wobble have been derived for certain input conditions. The method has been shown to compare closely with the numerical solutions of two sample problems. The sample problems also illustrated the relatively large effect of pitch and yaw jet damping on body motions.
Quantum mechanics - calculation of isomer ratios, particle emission and spin distribution in tin and indium
Magnetometer for determination of angular motion of spinning body in regular precession
Inertia product and inertia moment variation effect on spin entry, developed spin, and spin recovery of airplanes
Geometric factors for planetary thermal and reflected radiation on spinning and nonspinning spacecraft
Solar cell array deployment systems applied to spinning satellites based on flexible substrates and chemical rigidization
Gravity gradient torque effect on spin axis motion of asymmetric vehicle in precessing circular orbit of oblate earth
Aerodynamic torque on spinning spherical satellite
Spin axis determination of rotating satellite from ground track data
Aerodynamic torque equations for axis motion of spinning spherical satellite
Relation between angle of attack envelopes and correlation parameter for spinning bodies entering atmosphere at large inclinations
Final spin states of planets and satellites, deriving criteria for synchronous rotation
Spin-free transition density matrices, using permutation group algebra
Single-axis meter design and development for measuring feeble torques on massive bodies, discussing calibration, testing results, evaluation of static dipole moments and spacecraft spin-rate control moments
Structural stress and deflection and electrical performance analyses of boom antenna configurations for spinning navigation satellite
An analytical study has been made to investigate the relationship between the magnitude of the applied spin recovery moment and the ensuing number of turns made during recovery from a developed spin with a view toward determining how to interpolate or extrapolate spin recovery results with regard to determining the amount of control required for a satisfactory recovery. Five configurations were used which are considered to be representative of modern airplanes: a delta-wing fighter, a stub-wing research vehicle, a boostglide configuration, a supersonic trainer, and a sweptback-wing fighter. The results obtained indicate that there is a direct relationship between the magnitude of the applied spin recovery moments and the ensuing number of recovery turns made and that this relationship can be expressed in either simple multiplicative or exponential form. Either type of relationship was adequate for interpolating or extrapolating to predict turns required for recovery with satisfactory accuracy for configurations having relatively steady recovery motions. Any two recoveries from the same developed spin condition can be used as a basis for the predicted results provided these recoveries are obtained with the same ratio of recovery control deflections. No such predictive method can be expected to give satisfactory results for oscillatory recoveries.