Draft:David Hoag

David Garratt Hoag (October 11, 1925 – January 19, 2015) was an American aeronautical engineer who was Director of the Apollo Program at the Massachusetts Institute of Technology's Instrumentation Laboratory, later renamed the Charles Stark Draper Laboratory. The Program was responsible for the Apollo Primary Guidance, Navigation, and Control Systems on the Apollo command module and the lunar landing spacecrafts. The Guidance and Navigation system consisted of an inertial measurement unit, optical alignment telescope and space sextant, and Apollo guidance computer, which was used during the Apollo missions.

Early life and education
Hoag was born in Boston, Massachusetts on October 11, 1925 to Helen Garratt and Alden Hoag. After graduating from Chapel Hill-Chauncy Hall School in Waltham, he joined the Navy and stayed in the military while attending the Massachusetts Institute of Technology, where he received a bachelor’s degree in electrical communications and a masters in aeronautical engineering instrumentation.

Career
At MIT Instrumentation Laboratory, Hoag worked on the antiaircraft fire control systems and was Chief Technical Design Engineer and Program Manager for the Polaris Fleet Ballistic Missile Program.

He initially had the same role for Apollo before becoming Director in 1966. As part of the program, most of the focus was on the gyroscopic units, which had to be carefully constructed and fail-safe so the astronaut crew would not be endangered if one drifted and to keep the gimbals from freezing and locking up. Things were tweaked and re-tested as the program continued so that the guidance system would handle the load for the moon landing in 1969. Hoag oversaw this all, ensuring the work was completed to specification. NASA then asked the lab to take on the additional work of creating a digital flight control system. The laboratory was responsible for the programming and test verification of both Command and Lunar Module GN&C computer programs for each Apollo mission. Over the course of the program this involved 12 missions of which 6 landed on the moon. The development of both digital and hybrid simulators was also a major part of this effort for software verification.

Later, when the MIT Instrumentation Laboratory became the Draper Laboratory, he became the Head of the Advanced Systems Department, where he led activities on precision pointing and tracking, as well as surveillance systems that would orbit in space. He retired as Senior Technical Advisor in 1989 and remained as a consultant for the lab in 2005.

Professional associations
President of the Institute of Navigation 1978-1979, member of Defense Science Board, Fellow and later Chairman in 1980-1981 of the American Institute of Aeronautics and Astronautics, Chairman of the Navy Trident Flight Test Analysis Review Group 1981, the Naval Studies Board Panel on Advanced Navigation Technology, and many national task groups involving navigation. Elected to both the National Academy of Engineering and the International Academy of Astronautics.

Patents

 * Electromagnetic isolator/actuator System---This invention relates to electromagnetic suspensions and, more particularly, relates to apparatus and methods for providing an electromagnetically suspended platform isolated from external vibration and motion and independently controlled in six degrees of freedom by electromagnetic inputs
 * Laser Pointing System---This invention relates to systems for aiming a beam of light from a moving vehicle, such as a space vehicle, in a desired direction which is specified by celestial or geographic coordinates.

Awards
Hoag received the Col. Thomas L. Thurlow Award in 1969 from the Institute of Navigation, the NASA Public Service Award in 1969, the Navy Certificate of Merit in 1970, and the American Institute of Aeronautics and Astronautic’s Louis W, Hill Space Transportation Award in 1972 along with Dick Battin.