1. Presented as Paper 69-874 at the AIAA Guidance,Control, and Flight Mechanics Conference, Princeton, N.J., August18-20,1969; submitted August 27, 1969; revision received April 17, 1970. Part of the work reported in this paper was supported by NASA Marshall Space Flight Center, Contract NAS8-20080.
2. An adaptive tracking filter for bending-mode stabilization.