Propulsion, Geomagnetic Field, Magnetic Sail, Magnetic Torquer Abstract: The concept of "field directed propulsion, " which was suggested by Spenny et al. and Nagashima in 1994, isbased on the magnetic force induced by "uniform" geomagnetic field. Through an analytical investigation, we present that this concept is principally invalid for their original utility. We show, however, that their idea on magnetic shielding can be applied to the improvements of propulsive performance of "magnetic sail" and/or controlling performance of "magnetic torquer."
This paper proposes a systematic method to determine failure modes in an aircraft automatic flight control system. The method is based on an on-line parameter estimation scheme to detect changes in dynamical properties of a system and identify the portion in failure. At the same time, several indices based on the robust control theory are introduced to examine the failures in the system. Taking a flight path control system as an example, computer analyses and simulations of showing the indices on a monitoring display are made to demonstrate the effectiveness of the proposed method.
Height stability of WIG is fundamentally important among whole problems of WIG flying quality. Kumar made first contribution for it, But he failed theoretical prediction of height stability of tandem type WIG. This paper presents prediction for some WIG types, tandem as well as ente and conventional airplane having T tail.
This paper describes time-frozen measurements using a CCD camera system for total radiation behind strong shock wave in a shock tube. The measurements are carried out for the shock velocity range from 6.8km/s to 12.5km/ s at the initial pressure range from 13.33Pa to 133.3Pa in air. The experimental results are compared with the numerical ones. There is a relatively good agreement between the experimental and numerical results at 10km/s shock velocity at the initial pressure 13.33Pa, although some discrepancies appear at the other velocity range. It is found that the full width at half maximum of profile of the first-peak becomes narrower and the thickness of radiation front becomes broader, as the shock velocity increases at the lower initial pressure. At the higher initial pressure, there is a limitation of spatial resolution in the present experiment.
The formulation of stresses of the honeycomb sandwitch panel in the vicinity of the enbedded stiffner are performed and the solution of the formula is made. Out-of-plane strength of the honeycomb sandwitch panel is derived using the analytical solution. Tests are performed to confirm it. Finite element analysis are also performed. As the result of these analysis and the tests, the stress distribution in the vicinity of the enbedded stiffner are derived and the effects of the face skin thickness and the honeycomb core thickness on the strength of the honeycomb sandwitch panel are also derived.