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
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.
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