Skylab Lesson 1 The Cost of Change
Nothing is free. The only issue to be addressed is the value against the cost.
Skylab Lesson 2 Plan Conservatively and Execute Boldly
The initial development program plan becomes the measure of progress. Since research and development programs are, by definition, not completely understood, good management will provide adequate reserves in time, resources, schedule, and performance. Once the program is underway, indecision costs time and money.
Skylab Lesson 3 Program Variables
Three items can be varied in a development program - cost, schedule, and program content. Establish the most important factors. Ensure that your priority matches that of your management.
Skylab Lesson 4 Program Reserve
Plan adequate reserve in resources, schedule, and performance.
Skylab Lesson 5 Program Initiation
Large development programs should not be started until a full estimate of the resources needed is available, with adequate reserves identified. The resources must include manpower and time requirements as well as funds. These resources must be fully committed and planned by all levels of decision prior to any large scale beginning of a project.
Skylab Lesson 6 Provide Flexibility in Planning
The late additions to program objectives can be extremely productive and may be more important than the initial detailed objectives. Prepare the program plan to be able to accommodate good ideas which are surfaced late in the development cycle. Be prepared to accept new ideas. Have a sufficient financial reserve in the late years.
Skylab Lesson 7 Organization
It is important that the roles and responsibilities of the program elements be understood by all participants in the development. For a large program with many dispersed participants, that understanding should be written and recorded.
Skylab Lesson 8 Use a Phase Approach to Development
Skylab Lesson 9 Configuration Control Procedures
The phased approach to development should be complemented by a progressively mature control of hardware design. Initially, the hardware design is merely conceptual in nature and may be described parametrically, by equations or design parameters, for example. At this stage, the subsystem designer should have little controls placed upon the details. The designer should be engaged in trade studies, sensitivity analyses, and design variations which will lead to the next phase of hardware control, "base lining the system." This base line permits concentration on a specific design and allows detail design to begin. After a system is base lined, the designer can only change the concept when there is due cause and only after notifying other program elements to assure that each subsystem designer is aware of the design of interfacing subsystems. At CDR (drawing release) the detail design is complete and then formal Configuration Control should be initiated. At this time a rigid process should be established which will ensure that a design modification is only undertaken for understood cause and the full cost, and interface impact is analyzed prior to initiating the change.
Skylab Lesson 10 Update Design Requirements
Review design requirements periodically to ensure the hardware continues to reflect the real program needs. Requirement maturity can affect not only the design, but also the test verification of design as well.
Skylab Lesson 11 Paper Review of Designs
Specific design reviews which are based upon an analysis of drawings can inadvertently overlook important features such as operational incompatibilities.
Skylab Lesson 12 Detailed Scheduling of Work
All fabrication, assembly, and checkout activities should be scheduled in detail, but rescheduled activities (sometimes called unscheduled work) should be even more carefully controlled and scheduled.
Skylab Lesson 13 Use of Common Test Procedures
When a component is to be tested at a number of locations (e.g., the development contractor's plant, the integration contractor's plant, and the launch site), decide upon a single format and approach for the conduct of the test, for control and approval of waivers or fixes, for configuration control, and for documentation in general. Use the same basic test processes at all of the test sites.
Skylab Lesson 14 Lack of Spares
It is not always economical to provide only one flight article without a ready spare.
Skylab Lesson 15 Indicators of Schedule Status
Skylab Lesson 16 Criticality Assessment
Documentation levels, controls, and redundancies can be determined by assigning a criticality to each subsystem, experiment, or component. A component determined to be vital for crew safety (Criticality 1) requires a complete set of documentation and controls. Systems with this criticality are extremely costly to develop and to control since the data package generally begins with the pedigree of the raw material and carefully documents and controls each step of the development, fabrication, and test process.
Components which are required for primary mission success (Category 2) can receive somewhat less rigid treatment although in actual practice the controls on Criticality 2 hardware are almost identical with Criticality 1 components. Items which affect secondary objectives should be placed in Category 3. Considerable relaxation of documentation and control is possible for components such as these. For example, qualification testing can be reduced and verification by analysis is acceptable. Verification by similarity (i.e., use in a comparable but not identical manner) can be utilized.
Peripheral items, such as cameras, small experiments, and crew equipment of a noncritical nature should be categorized as Criticality 4. These items require only enough documentation and controls to ensure they are safe and represent no hazard.
Skylab Lesson 17 Reduced Requirements for Experiments
Skylab Lesson 18 Subsystem Managers
Skylab Lesson 19 Use of Committees
Do not use committees for decisions. Committees are advisors and consultants.
Skylab Lesson 20 Incentive Contracts
Incentive contracts are an effective management tool to ensure a successful development. Award fee contracts should be considered for R&D contracts.
Skylab Lesson 21 Overruns
Skylab Lesson 22 Safety Concerns
Skylab Lesson 23 Decision Levels
Skylab Lesson 24 Disposition of Discrepancies
Skylab Lesson 25 Provide Operational Flexibility In Design
Skylab Lesson 26 Provide Excess Consumables
Design the systems on any spacecraft for a maximum of expendables and consumables. Assure that the quantities of these expendable items exceed those necessary for the design mission by a wide margin.
Skylab Lesson 27 Stowage Flexibility
Skylab Lesson 28 Trained Observers
Skylab Lesson 29 New Manufacturing Techniques
Skylab Lesson 30 New Electronic Components
Avoid the use of new electronic techniques and components in critical subsystems unless their use is absolutely mandatory.
Skylab Lesson 31 Single Point Ground
A single point ground should be provided.
Skylab Lesson 32 Deorbit
Skylab Lesson 33 Manufacturing Aids
Skylab Lesson 34 Redundancy Design
When designing redundancies into systems, consider the use of nonidentical approaches for backup, alternate, and redundant items.
Skylab Lesson 35 Combined Environments
Skylab Lesson 36 Rapid Reaction
Skylab Lesson 37. Lesson: Crew Checklists
Crew checklists used to describe operating procedures should be complete but should be kept simple. Backup procedures, redundant procedures, and trouble-shooting procedures should not appear on the primary checklists but, instead, should be referenced only.
Skylab Lesson 38 The Size of the Command Task
Skylab Lesson 39 Control Moment Gyros
Skylab Lesson 40 Lubrication of Rotating Machinery
If possible, positive lubrication methods should be included in the design of long-life rotating machinery, such as control moment gyros.
Skylab Lesson 41 Investigate All Failure Modes
Do not let concern and investigations of "probable" failure modes divert attention from less likely failures.
Skylab Lesson 42 Designers Should View Their Product
White room restrictions inhibit the detail designers from examining the hardware they are responsible for. Access to assembly areas should be controlled, but not eliminated.
Skylab Lesson 43 Vent Port Location
Skylab Lesson 44 Structural Analysis Instead of Test
Skylab Lesson 45 Eliminate B-Nuts. Braze All Fluid Lines
Skylab Lesson 46 B-Nuts
Skylab Lesson 47 Fluid Lines and Cables
Skylab Lesson 48 Stress Corrosion
Skylab Lesson 49 Sliding Aluminum Surfaces
Skylab Lesson 50 Small Orifices
Skylab Lesson 51 Use Fire Control Techniques When Designing Cables
Skylab Lesson 52 Window Design
Skylab Lesson 53 Gaseous Oxygen and Nitrogen
Skylab Lesson 54 Caution and Warning Memory
Skylab Lesson 55 Adjustable Caution and Warning Parameters
Skylab Lesson 56 Waste Management Facility
Skylab Lesson 57 Medical Requirements for Collection of Feces and Urine
Skylab Lesson 58 Software Development
Software development should receive the same attention and rigor as hardware development. Ground software should not be an exception. Milestones should be established and tracked with critical attention.
Skylab Lesson 59 Timing System
Skylab Lesson 60 The Need for a Teleprinter
Skylab Lesson 61 Message Identification
Skylab Lesson 62 Teleprinter Workload
Skylab Lesson 63 Two-Way Color Television Requirement
Two-way color television should be provided for all future space programs for effective data flow and communications. The required bandwidth and power should be made available.
Skylab Lesson 64 Television Tape Recorder Requirement
Skylab Lesson 65 Television Camera Dynamic Range
Skylab Lesson 66 Spacecraft Lighting
Skylab Lesson 67 Private Communications
Skylab Lesson 68 Communications for Morale Purposes
Skylab Lesson 69 End-to-End Communications Tests
Skylab Lesson 70 Configuration of Test Articles
Skylab Lesson 71 Experiment Objectives
Skylab Lesson 72 Schedule Reviews
Skylab Lesson 73 Schedule Adjustments
Skylab Lesson 74. Crew Time
Others - coming soon!
Mr. Dale D. Myers - Associate Administrator for Manned Space Flight
Dr. Christopher C. Kraft, Jr. - Director, Johnson Space Center
Mr. Leland F. Belew - Skylab Program Manager, Marshall Space Flight Center
Lt. General Thomas Morgan (USAF) - Skylab Program Manager, Kennedy Space Center
Mr. Richard G. Smith - Deputy Director, Marshall Space Flight Center; Manager, Saturn Project
Mr. Eugene F. Kranz - Director, Flight Operations for Skylab
Dr. Walter Kapryan - Director, Launch Operations at Kennedy Space Center
Captain Charles Conrad, Jr. - Astronaut, Commander of the first manned Skylab mission
Captain Alan L. Bean - Astronaut, Commander of the second manned Skylab mission
Col. Gerald P. Carr - Astronaut, Commander of the third manned Skylab mission
Dr. Robert A. Parker - Astronaut, Program Scientist, Skylab
Mr. Kenneth P. Timmons - Manager, Martin Marietta Corporation, Skylab Multiple Docking Adapter
Mr. Raymond A. Pepping - Manager, McDonnell-Douglas Astronautics Company
Mr. Fred Sanders - Manager, McDonnell-Douglas Astronautics Company, orbital workshop project.
Mr. Haggai Cohen - Director, Reliability, Quality, and Safety for Skylab
Skylab Kleinknecht Mr. Kenneth S. Kleinknecht - Skylab Manager, Johnson Space Center
Dr. George E. Mueller - Associate Administrator for Manned Space Flight
Skylab Disher Mr. John H. Disher - Deputy Director, Skylab Program
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Last Revised: February 03, 2010
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