Friday, March 16, 2012

Space Shuttle Aircraft Systems Engineering: MIT OpenCouseWare

This popped up on my youtube suggestions for some reason. I took introductory "unified engineering"  as a freshman at MIT. My father would bring home extra Aviation Week magazines from Boeing and I was quite into aircraft (still am, I can identify just about any aircraft before 1980 and most of the ones since then) but by by sophomore year, I vowed to go into a field where they would never lay anybody off... computers and software (dozens of jobs later I find out one of my high school pals who didn't go to a top 10 college is still happily working for his first job at Boeing testing systems for the 747-8, a company which still has an old-fashioned pension plan....) . One of my professors was Sheila Widnall who would become Air Force secretary, and we actually spent a couple of lectures looking at the dynamics of the Space Shuttle which was still on the drawing boards in 1976.

Aircraft Systems Engineering

As taught in: Fall 2005

The shuttle passes Mach 1, producing shockwaves.
The space shuttle passes through the sound barrier during ascent. (Image courtesy of NASA.)

Instructors:

Prof. Jeffrey Hoffman

MIT Course Number:

16.885J / ESD.35J

Level:

Graduate

Course Features

Course Highlights

This course was administrated by shuttle astronaut and MIT Professor Jeff Hoffman and Professor Aaron Cohen, who was the Space Shuttle Orbiter Project Manager. Guest speakers provide the majority of the content in video lectures, discussing topics such as system design, accident investigation, and the future of NASA's space mission.

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.

Lecture 1 video




Notes (pdf) (Cameraman does not show slides so they are in this document)


The Shuttle Origin
or
The Making of a new Program
by
Dale Myers Pre Lunar Landing Planning
 2/61-10/68 Jim Webb didn’t want future
plans—wanted to keep options open
 3/69-9/70 Tom Paine never saw a future plan
he didn’t like
 1/64-10/68-Lots of lifting body work
 10/68-early 70 NASA dreamed of ever
increasing budgets, and planned accordingly Initial Public Awareness
1969
 Agnew Study- with Bob Seamans, Tom Paine, Lee Dubridge
 Supported by NASA’s ideas
 30 ft Diameter, 12 man Space Station
 2 in earth orbit, one in Lunar orbit
 Lunar Base
 Two stage fully recoverable Shuttle
 100-150 flights per year
 SkyLab with 5 visits by Command Modules
 Continue Saturn 1b and Saturn V production
 Space tug for higher orbits than LEO
 Nuclear stage for Moon and Mars
 Mars program by 1983 Meanwhile, the Budget Crash
 Euphoria of 1968 followed by severe cuts
 Vietnam, Great Society budget deficits were
causes, Nixon not a big supporter
 1966 MSF budget=$3.8B, 1972=$1.7B
 Was there going to be a human space
program at all?
 Mueller leaves in late 1969
 Paine leaves in late 70 (Low acting Admin.)
 Myers (1/70) and Fletcher (4/71) NASA Strategy-1970
 Shuttle is first priority, because low cost to space will
encourage all the Agnew Report items later
 Start 2 stage Shuttle Phase B, and
 Cancel Apollo 18 and 19 and Saturn 1b and V
 Cancel 2
nd
Skylab and CSM’s
 Cancel 30 ft. Space Stations
 Don’t start Space Tug
 Don’t start Nuclear Stage
 Cancel Mars program
Industry down from 400,000 to 150,000The Concept for a Shuttle
 Reusability equals low cost
 “you wouldn’t fly to New York and throw away the
airplane”
 Since R & D is higher, need many flights to
beat ballistic systems
 The lower the R & D the less flights needed
to beat ballistic systems
 If flights are many (because cost/flight is so
low) a two stage, fully reusable system is
right 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
 Navaho M=3 parallel tank separation Burnelli Lifting BodyEvolution of the Shuttle
1969-1971
 Fully reusable two stage Straight wing, like
an X-15
 Internal fuel
 Metal shingles (or unobtainium or some ablative)
 20000 lb. payload, due east
 Payload bay 12X40?
 400 miles crossrange
 100 to 150 flights/year
 $5 Million/flight in 1970 dollars Meanwhile, the Mission Model
 When the Space Station, lunar base, etc.
disappeared, we needed more payloads
(50+/year)
 Military agreed to put all payloads on Shuttle if we
increased payload and designed for 1500 miles of
crossrange, and met our cost/flight estimates.
 Commercial agreed to carry all payloads on
Shuttle (assumed we would develop a low cost
upper stage and meet cost/flight estimates).
 Science bought space servicing (i.e. Hubble) and
a low cost reusable platform Evolution of Requirements
(mostly from Military Requirements)
 Payload increased to 40,000 lbs Polar
 Crossrange increased to 1500 miles
 Payload bay increased to 15 by 60
 Non ablative reusable thermal protection
 Two fully recoverable piloted stages
 Automatic checkout and 30 day turnaroundEvolution II
 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
 15 x 60 payload bay (15 for Space Station, 60 for
military)
 40,000 lb. payload, polar
 Parallel External throwaway monocoque tank
 2 Recoverable, abortable solids
 Liftoff thrust augmentation with engines in Orbiter Resulting Program
Nixon Start on Jan. 5, 1972
5 Orbiters
 Reusable Orbiter and engines, reusable solid
cases, expendable fuel tank
 40 to 50 flights per year
 $10M-$15M per flight in 1970$
 $5.2B+20% reserve for R & D in 1970$*
• *As soon as Nixon left office, OMB forgot the 20% reserve
• NASA Comptroller (pressed by OMB) didn’t agree to 1970 base 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 Issues cont’d
 2 Solids vs. 1 or 2 Liquid strapons
 Two solids could be shipped by rail
 Solids had a better reliability record
 Solids could be recovered (industry studied pressure fed)
 Designers thought they could turn off solids.
 Later found they could not
 Thermal Insulation
 Ceramic tiles, carbon carbon, and external insulation
blankets (all new)
 High pressure staged combustion engine (new)
 Crew escape. (Only with complete structure)
 Operations Costs Operations Costs
 Enormous confidence from the Apollo program
 Studies by American Airlines, IDA and the Aerospace
Corporation nearly confirmed NASA operations costs
 NASA thought they had enough reliable, space based hardware
in the industry to support quick turnaround, easy to maintain
hardware
 NASA did not properly account for costs associated with:
 Post flight maintenance
 Assuring safety of flight in a hostile environment
 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 $302MShuttle 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)
 Missed operations costs. A two stage reusable system would
have missed worse. Spacecraft are not “like an airplane”. Spacecraft are not like Airplanes
 Every flight is a “structural dive demo.”
 No reusable space system gets millions of
hours of stressed operation
 No reusable space system develops decades
of evolutionary model improvement
 Every reusable system is exposed to
enormous environmental variations
 Thermal, vibration, pressure, Mach Number So, 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


Here is the lecture series


Video Lectures

The lectures from this course are available in video and audio formats. In many cases, the lecture slides are available to follow along with the videos, and biographies provide background of the guest speakers' careers.

Lecture 1: The Origins of the Space Shuttle

Lecture 2: Space Shuttle History

Lecture 3: Orbiter Sub-System Design

Lecture 4: The Decision to Build the Shuttle

Lecture 5: Orbiter Structure + Thermal Protection System

Lecture 6: Propulsion - Space Shuttle Main Engines

Lecture 7: Aerodynamics - (From Sub - to Hypersonic and Back)

Lecture 8: Landing and Mechanical Systems

Lecture 9: OMS, RCS, Fuel Cells, Auxiliary Power Unit and Hydraulic Systems

Lecture 10: The DoD and the Space Shuttle

Lecture 11: Use of Subsystems as a Function of Flight Phase

Lecture 12: Aerothermodynamics

Lecture 13: Environmental Control Systems

Lecture 14: Ground Operations - Launching the Shuttle

Lecture 15: Space Shuttle Accidents

Lecture 16: Guidance, Navigation and Control

Lecture 17: Mission Control 1

Lecture 18: Mission Control 2

Lecture 19: Design Process as it Relates to the Shuttle

Lecture 20: EVA and Robotics on the Shuttle

Lecture 21: Systems Engineering for Space Shuttle Payloads

Lecture 22: Test Flying the Space Shuttle

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