Communication to : 17th congress of the International Council of the Aeronautical Sciences, Stockholm, Sweden, Sept. 9-14, 1990. In : Journal of aircraft, vol. 30, no 5, 1993, p. 561-570SIGLEAvailable at INIST (FR), Document Supply Service, under shelf-number : 22419, issue : a.1994 n.1 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc