Lecturer: Professor Aaron Cohen
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:
1952 fully reusable launch vehicle concept discussed
1962 fully reusable vehicle seriously considered.
Air Force studied project dynasoar, cancelled in
1969 NASA adopted the idea of a fully reusable space ship

Top Level Requirements: fully reusable, 14 day turn around to next flight, deploy and retrieve payloads, design, development & test phase estimated to be 5.1b in 1971 dollars. Original cost per flight for 65,000 pounds was 10.5m per flight in 1971 $ for a flight rate of 60 per year

Shuttle studies: Phase “A” studies conducted to determine basic requirements and their effect on design in 1969
Principal Issues: size and weight of payload, cross range of the orbiter, heat-resistant structure or reusable insulating material, hypergolic reaction control system or liquid oxygen/hydrogen, fly- by-wire flight control system, wind tunnel tests to determine wing size and configuration, air breathing engines were considered for fly back; later were determined to be too heavy, entry techniques, landing speed, approach patter.

Shuttle Studies: Phase “B” studies were performed in mid 1970’s to determine a preliminary design.
Results: fully recoverable orbiter, disposable fuel tank, parachute-recoverable solid rocket boosters, high performance hydrogen-oxygen engines placed in the orbiter to be recovered, fully reusable with fly-back booster was greater than 5.1b. Many configurations were studied. Turn around time required landing a winged vehicle on a runway. Payload deployment and retrieval requirement determined location of orbiter on launch configuration.

Major shuttle configuration decisions: hydrogen/oxygen main engines. Sized the liquid oxygen/hydrogen tank, which is not reusable. Solid rocket boosters provided the additional propulsion required to get the orbiter into earth orbit. Solid rocket boosters designed to be recovered and re-used. Orbiter entry cross range required delta wings. Deletion of air breathing engines for moving orbiter required the Boeing 747 to carry the orbiter. FO/FS guidance, navigation, and control system. Fly- by- wire with a digital auto pilot. Size of payload bay 60 feet long by 15 feet diameter. Size of crew cabin defined to be over 2600 cubic feet. Payload 65,000 pounds at lift off and 35,ooo pounds at landing. The orbiter is a launch vehicle, a space craft, and an aircraft.

Hardware Sub-Systems: thermal protection system, structures, space shuttle main engines, hydraulic, aux power, fuel cells. OMS, & RCS systems. Guidance, navigation, and control. Environmental control & life support in crew cabin. Landing & mechanical systems, communications, electrical power.

Orbiter Sub-Systems: functions that are required to be performed (functional requirements), performance that is required (performance requirements), weight, interfaces, available technology, schedule, cost
Analytical Studies: aerodynamics, aerothermodynamics

1. The Origins of the Space Shuttle
2. Space Shuttle History
3. Orbiter Sub-System Design
4. The Decision to Build the Shuttle
5. Orbiter Structure and Thermal Protection System
6. Propulsion - Space Shuttle Main Engines
7. Aerodynamics - (From Sub - to Hypersonic and Back)
8. Landing and Mechanical Systems
9. OMS, RCS, Fuel Cells, Auxiliary Power Unit and Hydraulic Systems
10. The DoD and the Space Shuttle
11. Use of Subsystems as a Function of Flight Phase
12. Aerothermodynamics
13. Environmental Control Systems
14. Ground Operations - Launching the Shuttle
15. Space Shuttle Accidents
16. Guidance, Navigation and Control
17. Mission Control 1
18. Mission Control 2
19. Design Process as it Relates to the Shuttle
20. EVA and Robotics on the Shuttle
21. Systems Engineering for Space Shuttle Payloads
22. Test Flying the Space Shuttle
23. Exemplary Lecture: Shuttle Operations Video

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