
Lecture Description
Lecturers:
Dr. Jeffrey A. Hoffman is Professor of the Practice of Aerospace Engineering in the Department of Aeronautics and Astronautics at MIT. Dr. Hoffman received a B.A. (summa cum laude) from Amherst College in 1966 and a Ph.D. in astrophysics from Harvard University in 1971. He subsequently received a M.Sc. in Materials Science from Rice University in 1988. He spent one year as a post-doctoral fellow at the Smithsonian Astrophysical Observatory, after which he worked on the research staff of the Physics Department at Leicester University in the UK (1972-1975) and MIT’s Center for Space Research (1975-1978). He was a NASA astronaut from 1978-1997, having made five space flights and becoming the first astronaut to log 1000 hours of flight time aboard the Space Shuttle. Dr. Hoffman was Payload Commander of STS-46, the first flight of the US-Italian Tethered Satellite System. He played a key role in coordinating the scientific and operational teams working on this project. Dr. Hoffman has performed four spacewalks, including the first unplanned, contingency spacewalk in NASA’s history (STS 51D; April, 1985) and the initial repair/rescue mission for the Hubble Space Telescope (STS 61; December, 1993). He worked for several years as the Astronaut Office representative for EVA and helped develop and carry out tests of advanced high-pressure space suit designs and of new tools and procedures needed for the assembly of the International Space Station. For several years, he was the astronaut office’s representative on the Payload Safety Panel. Following his astronaut career, Dr. Hoffman spent four years as NASA’s European Representative, based at the US Embassy in Paris, where his principal duties were to keep NASA and NASA’s European partners informed about each other’s activities, try to resolve problems in US-European space projects, search for new areas of US-European space cooperation, and represent NASA in European media. In August 2001, Dr. Hoffman joined the MIT faculty, where he teaches courses on space operations and design and space policy. Dr. Hoffman is director of the Massachusetts Space Grant Alliance, responsible for statewide space-related educational activities designed to increase public understanding of space and to attract students into aerospace careers. His principal areas of research are advanced EVA systems, space radiation protection, management of space science projects, and space systems architecture.
Professor Aaron Cohen was born in Corsicana, Texas, on 5 January 1931. He received a B.S. degree in Mechanical Engineering from Texas A&M University in 1952 and an M.S. degree in Applied Mathematics from Stevens Institute of Technology in 1958. He received an Honorary Doctor of Engineering from Stevens Institute of Technology (1982) and an Honorary Doctor of Humane Letters from University of Houston-Clear Lake (UH-CL) (1989). In August 1993, Professor Cohen was appointed H.B. Zachry Professor of Engineering at Texas A&M University, where he taught senior mechanical engineering design. In August 2000 he became a professor emeritus of mechanical engineering. Professor Cohen served as Director of NASA's Lyndon B. Johnson Space Center in Houston, Texas, culminating a career that began there in 1962. He held several positions leading to his appointment as Manager of the Command and Service Module in the Apollo Spacecraft Program Office. In 1972, he was named Space Shuttle Orbiter Project Manager, responsible for design, development, production, and test flights. In 1982, as Director of Research and Engineering, he directed and managed all engineering and life science research and development. In 1986, Professor Cohen was named Center Director, directing approximately 3,600 NASA employees and 14,000 support contractor personnel. In addition, he served for a year as the Acting Deputy Administrator of NASA. Professor Cohen is a Fellow of American Astronautical Society (AAS), an Honorary Member of the American Society of Mechanical Engineers, and an Honorary Fellow in American Institute of Aeronautics and Astronautics. At NASA, he was awarded two Exceptional Service Medals, two Outstanding Leadership Medals, and four Distinguished Service Medals. Other awards include Presidential Rank of Meritorious Executive for Senior Executive Service (SES) (1981); Distinguished Executive for SES (1982, 1988); AAS’ W. Randolph Lovelace II Award, Space Flight Award, and President's Certificate of Recognition; AIAA Von Braun Award for Excellence in Space Program Management; Goddard Astronautics Award (1996); Von Karman Lectureship in Astronautics; 1984 ASME Medal; Texas A&M College of Engineering Alumni Honor Award (1987), Distinguished Alumni Award (1989); and UH-CL Distinguished Leadership Award (1988). He was elected a member of National Academy of Engineering (1988), was a joint recipient of the 1989 Goddard Memorial Trophy, and was awarded the Gold Knight of Manage¬ment Award, NMA Texas Gold Coast Council (1989). He received the Senior Executives Asso¬ciation Professional Development League Executive Excellence Award for Distinguished Executive Service and the National Space Trophy from the Rotary National Award for Space Achievement Foundation, and the 1992 Roger W. Jones Award for Executive Leadership from American University. Professor Cohen has authored many articles for scientific and technical journals and publications and presented the Lawrence Hargrave Lecture at the International Aerospace Congress in 1991.
Topics Included:
The Shuttle Origin or The Making of a new Program. Dale Myers. Pre Lunar Landing Planning. Jim Webb didn’t want future plans. Tom Paine. NASA increasing budgets, Agnew Study with Bob Seamans, Tom Paine, Lee Dubridge, 12 man Space Station, Lunar orbit, Lunar Base, Two stage fully recoverable Shuttle, SkyLab with 5 visits by Command Modules. Mars program by 1983, Vietnam, Great Society budget, Nixon not a big supporter. Mueller leaves in late 1969, Paine leaves in late 70, Myers (1/70) and Fletcher (4/71). NASA Strategy-1970, Shuttle is first priority, Start 2 stage Shuttle Phase B. Cancel Apollo 18 and 19 and Saturn 1b and V, Cancel 2nd Skylab and CSM’s, Cancel Mars program, Reusability equals low cost. Ballistic systems. The Technology Development 1950-1970, Burnelli lifting body. X-20 Dynasoar delta wing, HL-10 Lifting body, X-24A-Lifting body, X-15-Winged, internal fuel, X-15-Winged, internal and external fuel. Evolution of the Shuttle 1969-1971. Metal shingles (or unobtainium or some ablative), Payload bay 12X40, space servicing (i.e. Hubble). Evolution of Requirements, Non ablative reusable thermal protection, Two fully recoverable piloted stages. Automatic checkout and 30 day turnaround. Phase B showed Development of two stage fully recoverable Shuttle costs $14B for R&D. Nixon says “Build any shuttle you want as long as it doesn’t cost more than $5B”, OMB says “make it cost effective”. NASA looked for alternatives with new Phase A. Single Stage to orbit, Trimese, X24B surrounded with tanks, External Orbiter tanks, Parallel or series booster. The Mathematica Study. To convince OMB, Nixon and Congress we hired Mathematica to do cost effectiveness study, Results showed today’s configuration best, Delta wing for crossrange. Weight increase for military payloads, Parallel External throwaway monocoque tank, 2 Recoverable, abortable solids. Liftoff thrust augmentation with engines in Orbiter Resulting Program, Reusable Orbiter and engines. Reusable solid cases, expendable fuel tank. Design Issues, Straight vs Delta wing, Delta wing required for crossrange. External vs internal tank(s), External much lighter. Fuel transfer difficult. Thermal Insulation. Ceramic tiles, carbon-carbon and blankets. Solids or liquid booster. Solids looked more reliable and cheaper R&D. Engine location and type, Start on ground safer, better performance. Staged combustion better performance. Retractable turbojets. No-Depend on low L/D landings. Series vs parallel boosters. Series heavy, less performance Design. 2 Solids vs. 1 or 2 Liquid strapons. Solids had a better reliability record. Thermal Insulation, Ceramic tiles, carbon-carbon, and external insulation blankets. High pressure staged combustion engine. Crew escape. Operations Costs. Enormous confidence from the Apollo program. Studies by American Airlines, IDA and the Aerospace Corporation confirmed NASA operations costs. Difficult cutting edge technology (Engine and Thermal). FO/FO/FS. Cost tradeoffs between R & D and Operations Operations Cost. In 1970, $10M/flight price was based on same accounting system used for Apollo-hands on only, with a separate account for overhead. With $400M/year overhead, and inflation according to the consumers price index, cost per flight would be:
-1970 1981 2005 40 flts/year, no overhead $10M $23M $50M 40 flts/year, include ovhd. $20M $45M $101M
- 8 flts/yr, include overhead $60M $135M $302M
Shuttle Performance. The Shuttle has done everything it was designed to do. It has delivered Military, commercial, and scientific payloads to LEO and GEO, retrieved and replaced satellites, repaired spacecraft, and launched elements of the Space Station. In the 80’s, shuttle had 4% of launches, 41% of mass launched. Shuttle R&D was within what Nixon and Fletcher agreed. ($5.2B +20% reserve in 1970$). Missed two key design issues (cold O rings and foam shedding). A two stage reusable system would have missed worse. Spacecraft are not “like an airplane”. No reusable space system develops decades of evolutionary model improvement. Every reusable system is exposed to enormous environmental variations. Thermal, vibration, pressure, Mach Number. For the next program, keep it simple. Don’t stretch the technology. Use good margins of safety. Keep it as small as possible. Carry as few passengers as possible. Carry people or cargo, not both. Keep requirements to a minimum. Use as many past components and systems as have been proven reliable. Design for operations. Easy access, one man can replace boxes, etc. Keep a program design reserve to reduce Ops. costs.
Course Index
- The Origins of the Space Shuttle
- Space Shuttle History
- Orbiter Sub-System Design
- The Decision to Build the Shuttle
- Orbiter Structure and Thermal Protection System
- Propulsion - Space Shuttle Main Engines
- Aerodynamics - (From Sub - to Hypersonic and Back)
- Landing and Mechanical Systems
- OMS, RCS, Fuel Cells, Auxiliary Power Unit and Hydraulic Systems
- The DoD and the Space Shuttle
- Use of Subsystems as a Function of Flight Phase
- Aerothermodynamics
- Environmental Control Systems
- Ground Operations - Launching the Shuttle
- Space Shuttle Accidents
- Guidance, Navigation and Control
- Mission Control 1
- Mission Control 2
- Design Process as it Relates to the Shuttle
- EVA and Robotics on the Shuttle
- Systems Engineering for Space Shuttle Payloads
- Test Flying the Space Shuttle
- Exemplary Lecture: Shuttle Operations Video
Course Description
16.885J offers a holistic view of the aircraft as a system, covering: basic systems engineering; cost and weight estimation; basic aircraft performance; safety and reliability; lifecycle topics; aircraft subsystems; risk analysis and management; and system realization. Small student teams retrospectively analyze an existing aircraft covering: key design drivers and decisions; aircraft attributes and subsystems; and operational experience. Oral and written versions of the case study are delivered. For the Fall 2005 term, the class focuses on a systems engineering analysis of the Space Shuttle. It offers study of both design and operations of the shuttle, with frequent lectures by outside experts. Students choose specific shuttle systems for detailed analysis and develop new subsystem designs using state of the art technology. http://ocw.mit.edu