- 著者
- HORIKOSHI Jiro
- 出版者
- 宇宙航空研究開発機構
- 雑誌
- ISAS report (ISSN:03721418)
- 巻号頁・発行日
- vol.30, no.5, pp.115-194, 1965-03
The present paper is intended to show that a deliberate reduction of the elevator control system stiffness effectively improves the flying qualities relevant to longitudinal maneuver of a piloted airplane (excluding a fully power controlled airplane with an at present commonly used feel mechanism) through the matching of the stability and control characteristics of the airplane with the physical and perceptive characteristics of the pilot. A properly selected stiffness of the control system will cause upward shift and flattening of the curves of stick travel per airplane response versus speed over wide ranges of speed and normal acceleration, and hence it will add a good measure of longitudinal maneuverability sensed by the pilot to the already established stick force per airplane response. Analytical investigations are made of the effect of the stiffness on the stick travel per airplane response in steady longitudinal maneuvers, and on the frequency response characteristics of the airplane to stick movement during unaccelerated flight. Numerical calculations, including an analog computer analysis of the effect on the responses stated above in the initial or transient state of longitudinal control, are made based on the data of a prototype airplane for which the author was responsible. The developments of the concept and the flight-tests of the said airplane which took place about twenty-six years ago are briefly described. Both results are fairly coincident with each other, and are further backed-up by ample service experiences on this airplane and its successors. Thus the effectiveness of the concept is sufficiently demonstrated. Also investigations are made of such characteristics as might be apprehended by some people to be adversely affected by the reduced stiffness. Confirmation is made that it is applicable to a subsonic airplane which is normally designed and not seriously affected by aerodynamic compressibility. It may be remarked that, being easy to apply and extremely simple in its applied form, the concept may give neat solutions to some of the problems in the field of mechanical as well as aeronautical engineering, in which means to provide self-adaptability and/or to soften responses are required. A spring tab may be cited as the second successful application of the concept to an airplane within the author's knowledge.
- 著者
- MIURA Koryo
- 出版者
- 宇宙航空研究開発機構
- 雑誌
- ISAS report (ISSN:03721418)
- 巻号頁・発行日
- vol.34, no.9, pp.141-163, 1969-11
A proposition of a new shell form, which is cylindrical in a macroscopic sense and is concave polyhedral in a microscopic sense, is the purpose of this paper. It is shown that the inextensional post-buckling configurations of general cylindrical shells subjected to axial loading have peculiar geometrical characteristics, and that these configurations compose a general group of surfaces which may be designated as the pseudocylindrical concave polyhedral surface. Then the fixed idea that these surfaces are essentially failed forms is abandoned and is replaced by the idea that these are the basic forms of a new shell which could function superbly as the structure under some loading conditions. It is shown that the new shell, which may be called for convenience, the pseudocylindrical concave polyhedral shell and the PCCP shell for its abbreviation, has many useful characteristics as follows; inclusion of an arbitrary curvature distribution, developability of its midsurface, intrinsically high circumferential bending rigidity, and simplicity of elementary faces. The application of PCCP shells to large span shell structures, reservoirs, expansion joints, and others is suggested.
- 著者
- OBAYASHI Tatsuzo KURIKI Kyoichi KAWASHIMA Nobuki NAGATOMO Makoto KUDO Isao NINOMIYA Keiken USHIROKAWA Akio Ejiri Masaki SASAKI Susumu
- 出版者
- 宇宙航空研究開発機構
- 雑誌
- ISAS report (ISSN:03721418)
- 巻号頁・発行日
- vol.43, no.8, pp.141-174, 1978-08
SEPAC (Space Experiment with Particle Accelerators) accelerators were tested in NASDA Large Space Chamber. The accelerators were Engineering Models of EBA (Electron Beam Accelerator) and MPD (Magnetoplasmadynamic arcjet). EMI (Electromagnetic Interference) data were obtained for EBA and MPD arcjet and no interference both electronic and via plasma was observed between these accelerators. Charge neutralization was successfully attained when MPD arcjet or NGP (Neutral Gas Plume) and EBA were simultaneously operated. Beam and plasma injections were clearly observed by a monitor TV camera.