![]() |
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
![]()
So I don't know if this is the right group but whatever.
So I've been reading speculation on the CEV's shape, and I got to wondering. If it where a winged or lifting body design, how would you attach a LEM? I would imagine that the configuration would be along the lines of Apollo, with some type of SM in the back, with the lunar module in the front. If you were to attach it to some kind of docking port on the nose of the CEV, wouldn't the presence of the docking hardware make reentry difficult? ( like seams and stuff). And if you didn't attack the LEM to the nose, where would you put it, if you stuck it on top, would it get torqued off or something? |
#2
|
|||
|
|||
![]()
"Steve" wrote in message
oups.com... So I don't know if this is the right group but whatever. So I've been reading speculation on the CEV's shape, and I got to wondering. If it where a winged or lifting body design, how would you attach a LEM? I would imagine that the configuration would be along the lines of Apollo, with some type of SM in the back, with the lunar module in the front. If you were to attach it to some kind of docking port on the nose of the CEV, wouldn't the presence of the docking hardware make reentry difficult? ( like seams and stuff). And if you didn't attack the LEM to the nose, where would you put it, if you stuck it on top, would it get torqued off or something? I somehow don't see the first vehicle being winged. What is the point? However, if you were going to create such a vehicle, it would not take much to think of ways around your self created problem. If we are having other modules, then why not a re entry fairing to dock to? I'd persoanlly imagine the docking area would be on top though, inside some doors as per Shuttle, as you would probably still need radiators, and possibly solar panels as well, so why re-invent the wheel? Hide the docking hardware inside doors containing these on the upper surface and the underside of the doors. Brian -- Brian Gaff....Note, this account does not accept Bcc: email. graphics are great, but the blind can't hear them Email: __________________________________________________ __________________________________________________ __________ |
#3
|
|||
|
|||
![]() Steve wrote: So I don't know if this is the right group but whatever. So I've been reading speculation on the CEV's shape, and I got to wondering. If it where a winged or lifting body design, how would you attach a LEM? I would imagine that the configuration would be along the lines of Apollo, with some type of SM in the back, with the lunar module in the front. If you were to attach it to some kind of docking port on the nose of the CEV, wouldn't the presence of the docking hardware make reentry difficult? ( like seams and stuff). And if you didn't attack the LEM to the nose, where would you put it, if you stuck it on top, would it get torqued off or something? The configuration is To Be Determined right now. At present, contractors are preparing to compete for a chance to build the boilerplate Crew Exploration Vehicle (CEV) component. The "Lunar Surface Access Module" (LSAM) and "Earth Departure Stage" (EDS) would be developed for "Spiral 2" of the Constellation Program. Spiral 2 won't happen for years, and then only if some future Administration/Congress approves the funding. Among the many unknowns is what the CEV Launch Vehicle (CEVLV) is going to be. If CEVLV is tailored for Low Earth Orbit (LEO) CEV missions (Spiral 1 requirement), then if seems likely that a Spiral 2 CEV would be launched separately from the LSAM/EDS components, to perform an Earth Orbit Rendezvous type mission. EDS/LSAM could be launched in pieces by several existing "Heavy" boosters, or all at once by one really big new launch vehicle. The new NASA administrator is said to favor the latter approach, but the final decision will all come down to cost and funding. For an overview, read Attachment J-1 at the following link. "http://prod.nais.nasa.gov/cgi-bin/eps/sol.cgi?acqid=113638" - Ed Kyle |
#4
|
|||
|
|||
![]() "Brian Gaff" wrote in message k... "Steve" wrote in message oups.com... So I've been reading speculation on the CEV's shape, and I got to wondering. If it where a winged or lifting body design... I somehow don't see the first vehicle being winged. What is the point? There wasn't much of a point in making the X-38 (and the CRV that would have followed) a lifting body. The faster, cheaper, better solution would have been to start with an Apollo CSM mold-line, perhaps scaled up a bit to take advantage of the shuttle's larger diameter payload bay and perhaps offset the CG a bit more to add more hypersonic lift to the design. If you want better control over the landing location, ditch the parachutes and use a large parafoil, just as X-38 had to due because its landing speed would have been far too high for comfort. Jeff -- Remove icky phrase from email address to get a valid address. |
#5
|
|||
|
|||
![]()
ed kyle wrote:
Among the many unknowns is what the CEV Launch Vehicle (CEVLV) is going to be. If CEVLV is tailored for Low Earth Orbit (LEO) CEV missions (Spiral 1 requirement), then if seems likely that a Spiral 2 CEV would be launched separately from the LSAM/EDS components, to perform an Earth Orbit Rendezvous type mission. EDS/LSAM could be launched in pieces by several existing "Heavy" boosters, or all at once by one really big new launch vehicle. The new NASA administrator is said to favor the latter approach, but the final decision will all come down to cost and funding. For an overview, read Attachment J-1 at the following link. "http://prod.nais.nasa.gov/cgi-bin/eps/sol.cgi?acqid=113638" It might be useful to post Attachment J-1 for reference here, as well as to protect against 404age. So here it is: ATTACHMENT J-1 STATEMENT OF OBJECTIVES Statement of Objectives for the Crew Exploration Vehicle 1.0 Introduction On January 14, 2004, the President of the United States directed the National Aeronautics and Space Administration (NASA) to embark on a robust space exploration program that will advance the Nation's scientific, security, and economic interests. To meet the goals and objectives of our new vision, NASA plans to deploy a set of systems, large and small, that will be integrated into a "system of systems". This includes Earth-to-orbit and in-space transportation systems, systems required for human health and performance, and robotic systems that will assist humans as they travel and explore. CEV is the first component in the system-of-systems that will be built under the NASA Constellation Program and is the subject of this request for proposals. 2.0 Scope The Statement of Objectives (SOO) for the Crew Exploration Vehicle represents a programmatic and technical baseline for the purposes of the Offeror's proposal. The SOO will be maintained and updated by NASA as a contractor programmatic and technical baseline until the System Requirements Review (SRR) (see Section 5). The SOO will be part of the Model Contract. The SOO is augmented by a Constellation System of Systems Point of Departure (POD) Architecture requirements suite through spiral 3 (see figure 1). NASA plans on developing a clear set of performance and functional requirements as well as external interface requirements for the CEV system by SRR (see Section 5). In the event of a conflict with the current revision of the Constellation System of System requirements suite the SOO will take precedence until SRR. 3.0 Spiral Development and Constellation Program Objectives A key challenge for NASA is to develop new capabilities in a manner that is pragmatic - so that new capabilities can be developed and used to advance exploration in the near term - while also being flexible, in order to incorporate new technologies and respond with agility to scientific discoveries. To meet this challenge, NASA will develop exploration capabilities in stages, or "spirals." Each spiral will usher in a set of major new capabilities in support of the Vision for Space Exploration. Spirals will be structured based on specific requirements, well-defined goals and endpoints, then-current technologies, management risks, an executable budget, and knowledge gained from prior in-space activities. NASA's acquisition strategy encourages the use of open-systems architectures that facilitate upgrades and augmentation while enabling interoperability among systems. Capabilities to be provided by the first three spirals a Spiral 1: Earth Orbit Capability. Spiral 1 establishes the capability to test and checkout crew transportation system elements in Low Earth Orbit in preparation for future human exploration missions to the Moon. As new exploration elements necessary for future spirals are developed, they will be tested with the Spiral 1 CEV in the space environment to prepare for future exploration. The objective of crewed access to low earth orbit will be met by 2014. Spiral 2: Extended Lunar Exploration. Spiral 2 establishes the capability to conduct human exploration missions on the surface of the Moon for extended durations. In this context, extended duration is defined as the capability to support the crew on the surface of the Moon for a minimum of four days. This objective will be met in the 2015-2020 timeframe. Spiral 3: Long Duration Lunar Exploration. Spiral 3 establishes the capability to conduct routine human long duration missions on the surface of the Moon to test out technologies and operational techniques for expanding the human presence to Mars and beyond. Missions in Spiral 3 will extend in duration from those obtained in Spiral 2 up to several months to serve as an operational analog of future short stay Mars missions. This objective will be met after 2020. A key aspect to spiral development will be to develop new technologies that improve performance and lower cost over time. This is crucial to maintaining affordability and achieving the Nation's goals for future exploration. Accordingly, major portions of NASA's resources have been allocated to technology development with two major portfolios, Exploration Systems Research and Technology (ESRT) and Human System Research and Technology (HSRT), specifically focused on the exploration mission. To build a sustainable program, all developments within the system-of-systems must have a strategy for incorporating new technologies that result from both NASA-sponsored and outside research. 4.0CEV Project Objectives An anchoring capability of the Constellation Program is a human-rated CEV that will carry human crews from Earth into space and back again. Coupled with transfer stages, landing vehicles, and surface exploration systems, the CEV will serve as an essential component of the architecture that supports human voyages to the Moon and beyond. Given an acquisition strategy utilizing spiral development, a system-of-systems implementation, and reliance on technology for sustainability and affordability, the following project objectives have been established: 1.Ensure that the CEV is designed from the outset as a key element of the Constellation "System of Systems" meeting at minimum Spiral 2 requirements with a clear plan to meet Spiral 3 requirements. Meeting Spiral 3 from the outset is a goal. 2.Ensure crew safety within the limitations of meeting system performance requirements and achieving mission objectives. 3.Design and execute a meaningful risk mitigation program that culminates in a risk reduction flight effort and PDR by the end of calendar year 2008. 4.Deliver a quality design that ensures simplicity and addresses all aspects of human spacecraft development, certification and operations. 5.Execute a human flight in 2014 utilizing a CEV. 6.Perform to an established cost, schedule and technical baseline. 7.Maximize the use of existing technology in the design of the CEV. 8.Base the vehicle design on an Open Systems Architecture. 9.Simplify the interface design between the CEV and other Constellation elements to optimize integration. 10.Certify by test to the maximum extent possible. 11.Develop technology portfolios and define requirements for advanced development projects for technology insertion. 12. Implement innovative designs for the CEV spacecraft and ground systems to achieve efficient and effective operations. This solicitation for the CEV component of the Crew Transportation System utilizes a phased approach. Phase 1 of the acquisition calls for a maximum of two contractors to: Evaluate NASA's ESRT and HSRT programs for potential CEV program integration as part of a concerted effort to improve system effectiveness and affordability. Conduct a series of trade analyses on critical performance drivers for the purposes of identifying threshold and objectives for the CEV system. Affordability, sustainability, and extensibility to future spirals will be the focus of the analyses. Participate fully in a System Requirements Review (SRR) to develop accurate, comprehensive, consistent, and verifiable requirements for the CEV system through Spiral 3 of the Constellation System of Systems. Conduct a System Definition Review (SDR) for the CEV system meeting at a minimum Spiral 2 with a clear implementation plan for Spiral 3. Conduct a Preliminary Design Review (PDR) for the CEV system meeting at a minimum Spiral 2 with a clear implementation plan for Spiral 3. Provide an iterative analysis of cost, risk and performance based on realistic timelines and estimates of cost. Conduct a comprehensive risk management program which will mitigate program uncertainties by establishing priorities, options, adequate margins of safety, and "off-ramps" for risk mitigation during Phase 1 and a plan to retire the residual risk during phase 2. Conduct a risk reduction flight effort to: (1) validate industry's capability to perform on cost, on schedule and on performance, and (2) retire associated CEV program risks (Flight Application of Spacecraft Technology (FAST)). CEV Phase 1 ends with a planned down select to a single prime contractor in late 2008. Phase 2 of the CEV acquisition calls for a single Contractor to complete the development, test, and deployment of a human-rated CEV. After completion of phase 2, the contractor shall provide, as Government options, sustaining engineering services and production capability to support additional flights and additional CEV spacecraft. The Government reserves the right to perform a down select at any time and to not select either contractor in 2008. 5.0 Requirements Baseline for Constellation NASA's process for formulating and prioritizing requirements is targeted to enable sustainable and affordable exploration. An overriding goal in the definition of the requirements set for future exploration systems is to maximize value while minimizing cost. This will be accomplished by: Architecture trade space evaluations via iterative analyses of cost, risk and performance based on realistic timelines and estimates of cost. Scheduling the incorporation of mature technologies to improve system effectiveness and reduce cost. Planning for uncertainties by establishing priorities, options, adequate margins of safety, and "off-ramps." Once finalized, the requirements are documented formally and approved by NASA. Once approved at the Agency level, requirements can only be modified by NASA. To allow flexibility in implementation, objectives and associated thresholds will be established for major design and cost drivers. NASA has defined an initial set of requirements for Spiral 1, 2, and 3 and identified major factors that drive performance and cost for the CEV. Based on these initial requirements, a technical solution has been developed using a Point-of-Departure (POD) architecture that meets the exploration objectives through Spiral 3 (see Figure 1 for POD Spec Tree and the following documents in attachment J-4: Constellation Requirements in ESMD-RQ-0010, -0011, -0012, -0013; CEV Concept of Operations in ESMD-RQ-0019). The POD will be used as a baseline against which cost and operational performance trades can be made with the goal of optimizing the exploration architecture and finalizing the Spiral 3 requirements at SRR in July, 2006. Salient features of the POD architectu Spiral 1 components include the CEV, a CEV launch vehicle, and ground support systems infrastructure. The CEV and launch elements will safely transport the crew from the surface of the Earth to Low Earth Orbit and return them to the Earth's surface at the completion of the mission. The Launch System provides the capability to launch the CEV to Low Earth Orbit. The CEV provides the necessary crew habitation functions during ascent, on-orbit, and entry, including mission aborts. Spiral 2 consists of the Spiral 1 elements, or derivatives of those elements, plus the Earth Departure Stage (EDS) to transport elements to the lunar vicinity as well as the Lunar Surface Access Module (LSAM) that provides the capability for the crew to access the lunar surface. The CEV provides crew habitation from launch to lunar orbit and return to the Earth surface, including aborts during Earth ascent. The CEV provides the transportation functions to return from lunar orbit to the Earth surface. The EDS provides the propulsive accelerations needed to transfer the various flight elements (CEV and LSAM) from Low Earth Orbit to lunar orbit and provides the deceleration for lunar orbit insertion. The LSAM provides the crew habitation and transportation functions from lunar orbit, to the lunar surface, and return back to lunar orbit. In addition, the LSAM provides the capability for the crew to conduct science and perform routine EVA on the surface of the Moon. Finally, the Cargo Delivery System (CDS) is used to deliver un-crewed elements to low Earth orbit and/or lunar orbit. The CDS consists of an EDS and a Cargo Launch Vehicle. Spiral 3 requires various additional surface elements to support the crew for the long duration missions. These surface elements have not been completely defined at this point, but will provide basic functional capabilities including habitation, communication, power, extended range mobility, enhanced science capabilities, and other functions. It must be emphasized that the requirements baseline captured in the point of departure architecture may be amended to reflect cost and performance trade analysis results conducted during the CEV Phase 1 activities. The process for requirements and integrated design development are documented in the Constellation SE&I White Paper: Constellation System Engineering Management White Paper (see Applicable Documents). NASA will maintain and update the SOO to reflect the evolution of the Constellation System of System requirements suite through SRR, as well as the Applicable Documents for the CEV system development activities. At SRR the CEV System Requirements Document (SRD) and External Interface Requirements Documents (EIRD's) will become the baseline for the CEV system. 6.0CEV Technical Requirements The contractor shall meet the following non-tradeable objectives: The CEV system shall: 1.Ensure crew safety through all mission phases within the limitations of meeting system performance requirements and achieving mission objectives. 2.Integrate with required elements of the Constellation System of Systems. Based on the POD architecture, a set of Initial Performance Parameters (IPPs) has been defined for the CEV. For purposes of this request for proposals, industry is expected to provide an initial concept for a CEV spacecraft that shall: 1.Have a total gross liftoff weight (GLOW) of less than 20 metric tons. 2.Provide an abort capability during all phases of flight. 3.Be 2-fault tolerant to hardware component failures within safety critical systems except where design to minimum risk is approved by NASA. 4.Integrate with the Launch Vehicle (LV) to achieve low earth orbit. 5.Integrate with the Earth Departure Stage (EDS) to achieve lunar orbit. 6.Integrate with the Lunar Surface Access Module to achieve lunar surface mission objectives. 7.Integrate with Ground Support Systems for launch processing and mission control. 8.Integrate with In Space Support Systems to support overall Constellation command, control, communication, and information requirements. 9.Be capable of orbital maneuvers and rendezvous/docking with other Constellation systems. 10.Be capable of return from lunar orbit to the earth surface without assistance from external Constellation elements. 11.Be capable of supporting human life from launch on the earth surface through mission complete on earth surface during a maximum CEV crewed mission duration of 16 days. 12.Abort capability independent of LV or EDS flight control. 13.Be capable of unmanned operations for test flight purposes during Spiral 1 efforts and during lunar surface activities for Spirals 2 and 3. 14.Minimizing ground processing interfaces while maintaining redundancy separation standards and minimizing potential hazards. 15.Provide the capability to conduct missions with 1, 2, 3, and 4 crewmembers with a minimum habitable volume of 3.54 cubic meters per crew member. These IPP's are not meant to curtail innovation or alternate architectural concepts during Phase 1 activities. To that end, a set of focused cost and performance trades will be conducted prior to SRR against these IPP's to include: 1.Launch weight mass trades (both increases and decreases), including taking advantage of performance gains by mass reduction during ascent 2.Ability to abort anytime during all mission phases 3.Inclusion of the LSAM functionality within the CEV system 4.CEV direct return vs. Earth Capture 5.Mission Duration (both manned and unmanned mission phases) 6.Crew size (up to 6 crew members) and crew habitable volume allocations. 7.Splitting CEV functionality into modules (e.g., earth surface to LEO, LEO to Lunar orbit, Lunar orbit to Earth return) 8.Human Rating Requirements cost drivers 9.CEV system support of spiral 3 10.CEV support for transfer of crew to and from International Space Station (ISS) 11.CEV support of Extra-Vehicular Activities (EVA) operations 12.Provisions for common Constellation System elements (eg Docking systems, Communication systems) Through this competition, industry partners will be selected to work with NASA in conducting cost/performance analysis for alternatives to the point-of-departure architecture and CEV requirements. At the same time, the CEV contractors will mature their designs for the CEV while working their risk reduction demonstrations. NASA's intent is to finalize the Spiral 3 requirements in July, 2006, complete the FAST and PDR in 2008, move onto final design and fabrication in support of the first crewed flight in 2014, and then continue on to the moon, Mars, and beyond. |
#6
|
|||
|
|||
![]() wrote in message ups.com... 15.Provide the capability to conduct missions with 1, 2, 3, and 4 crewmembers with a minimum habitable volume of 3.54 cubic meters per crew member. That's an odd number. By my calculations, that works out to a cube with a side of exactly 5 feet in length. So, what research did they use to arrive at exactly 125 cubic feet per crewmember? I wonder if the engineers at NASA are still working with feet and inches? ;-) Jeff -- Remove icky phrase from email address to get a valid address. |
#7
|
|||
|
|||
![]() |
#8
|
|||
|
|||
![]()
"Rick Nelson" wrote ...
Thanks Th, I refuse to use MS products and all the documents are in MS Word format Open Office |
Thread Tools | |
Display Modes | |
|
|
![]() |
||||
Thread | Thread Starter | Forum | Replies | Last Post |
The Gravitational Instability Cosmological Theory | Br Dan Izzo | Astronomy Misc | 0 | August 31st 04 02:35 AM |
OSP - capsule or lifting body? | Joseph S. Powell, III | Space Shuttle | 0 | January 28th 04 08:39 PM |
UFO Activities from Biblical Times (Long Text) | Kazmer Ujvarosy | UK Astronomy | 3 | December 25th 03 10:41 PM |
UFO Activities from Biblical Times (LONG TEXT) | Kazmer Ujvarosy | SETI | 2 | December 25th 03 07:33 PM |
UFO Activities from Biblical Times | Kazmer Ujvarosy | Astronomy Misc | 0 | December 25th 03 05:21 AM |