David F. Williams

Retired Aerospace Engineer: Trajectory Optimization, Guidance and Control Analysis, Modeling and Simulation


Education:  BE, Engineering (EE), Vanderbilt University, 1960 (Magna Cum-Laude).
Graduate Engineering Courses (24 semester hours), University of Alabama, 1961.


Career:  1986-2007: Senior Principal Engineer and Branch Manager, Dynetics, Inc., Huntsville, AL.  Led development of earth orbital mission analysis computer program for NASA's Marshall Space Flight Center. Led feasibility study (for Wright Patterson Air Force Base) of the use of trajectory optimization methods to reduce the cost of preflight-planning for the ascent of heavy-lift launch vehicles. Led the development of fire-control and guidance concepts for a hit-to-kill hypervelocity projectile. Developed high-fidelity autopilot math models and 6DOF dynamics models for hardware-in-the-loop flight simulations of surface-to-air and air-to-surface guided missiles. Developed high-fidelity models of the dynamics and track and stabilization loops of two- and three-gimbaled sensors. Analyzed boost guidance algorithms and developed a trajectory optimization computer program for surface-to-surface missiles.

1978-1986: Senior Principal Engineer and Dept. Manager, Computer Sciences Corp., Huntsville, AL. Led the development of a film-and-video-based simulator for the training of gunners for the Army's Fiber Optic Guided Missile (FOG-M). Led the development of a man-in-the-loop simulator for guidance of a Hellfire missile with IR imaging seeker, including development of the computer-generated target and background imagery.

1971-1978: Engineer Specialist and Branch Chief, Northrop Services, Inc., Huntsville, AL. Developed a novel and highly-effective trajectory optimization method based on Linear Programming's Simplex algorithm, and used this method to define constrained optimum reentry trajectories for the Space Shuttle orbiter. Led the development of a method to define the boost-phase steering profile for the Space Shuttle launch vehicle. Led the development of a mission-planning methodology for earth orbital missions. Defined modifications to the Space Shuttle's ascent guidance algorithm whereby return-to-launch-site constraints are applied to the ascent steering profile.

1963-1971: Research Engineer, The Boeing Company, Huntsville, AL.  Applied the calculus of variations to the optimization of endo- and exo-atmospheric rocket trajectories. Developed necessary conditions for the optimal steering, coasting, and staging of a multi-stage launch vehicle. Analyzed the ability of a human pilot to guide the Saturn V launch vehicle from launch to earth orbit.

1961-1963: 1st Lt. at Fort Sill's USAAMS (with time off as Forward Observer at Fort Benning). Managed a group of officers, enlisted men, and contractors who instructed officers and enlisted men in the theory and operation of the Army's Corporal missile system. Served on the Operations Staff of the Guided Missile Department of the US Army Artillery and Missile School, and completed the jump training course at the Army Airborne School, Fort Benning, GA.

1961 (summer): Research Engineer, The Boeing Company, Seattle, WA.  Assisted in the development and checkout of a man-in-the-loop analog computer simulation of a rendezvous between two earth-orbiting spacecraft.