Engineering topics

Hypes, Warren D.

Publications and source records attributed to Hypes, Warren D..

14 records

NASA NTRS1992

The environmental control and life-support system for a lunar base: What drives its design

The purpose of this paper is to identify and briefly discuss some of the ground rules and mission scenario details that become drivers of the environmental control and life support (ECLS) system design and of the logistics related to the design. This paper is written for mission planners and non-ECLS system engineers to inform them of the details that will be important to the ECLS engineer when the design phase is reached. In addition, examples illustrate the impact of some selected mission characteristics on the logistics associated with ECLS systems. The last section of this paper focuses on the ECLS system technology development sequence and highlights specific portions that need emphasis.

Hypes, Warren D.↗

NASA NTRS1992

Lunar Habitat Would Be Assembled In Space

Conceptual lunar habitat built inside external tank from National Space Transportation System (NSTS). Tank modified in low Earth orbit using existing structures and openings for access without compromising structural integrity. Designed for unmanned transport to orbit around Moon, and autonomous soft landing. Houses crew of 12 for 70 days between resupply missions.

King, Charles B.↗

NASA NTRS1992

Method of providing a lunar habitat from an external tank

A lunar habitat is provided by placing an external tank of an orbiter in a low Earth orbit where the hydrogen tank is separated from the intertank and oxygen tank which form a base structure. The base structure is then outfitted with an air lock, living quarters, a thermal control system, an environmental control and life support system, and a propulsion system. After the mounting of an outer sheath about the base structure to act as a micrometeoroid shield, the base structure is propelled to a soft landing on the moon. The sheath is mounted at a distance from the base structure to provide a space therebetween which is filled with regolith after landing. Conveniently, a space station is used to outfit the base structure. Various elements of the oxygen tank and intertank are used in outfitting.

King, Charles B.↗

NASA NTRS1992

Design and technology assessment of three lunar habitat concepts

Three manned lunar habitat concepts, designed to support a crew of four for 28-30 days, are presented. Two concepts are based on Space Station Freedom structural elements and the third uses an earlier expandable-module-technology base. Technology readiness criteria, developed for assessing NASA sponsored developments, are applied to technology development needs for each concept to estimate the present level of technology readiness.

Hypes, Warren D.↗

NASA NTRS1991

Design and logistics of integrated spacecraft/lander lunar habitat concepts

Integrated spacecraft/lander combinations have been designed to provide a support structure for thermal and galactic radiation shielding for three initial lunar habitat concepts. Integrating the support structure with the habitat reduces the logistics requirements for the implantation of the initial base. The designs are simple, make use of existing technologies, and minimize the amount of lunar surface preparation and crew activity. The design facilitates continued use of all elements in the development of a permanent lunar base and precludes the need for an entirely different structure of larger volume and increased complexity of implantation. This design philosophy, coupled with the reduced logistics, increases overall cost effectiveness.

Hypes, Warren D.↗

NASA NTRS1991

Global change technology architecture trade study

Described here is an architecture trade study conducted by the Langley Research Center to develop a representative mix of advanced space science instrumentation, spacecraft, and mission orbits to assist in the technology selection processes. The analyses concentrated on the highest priority classes of global change measurements which are the global climate changes. Issues addressed in the tradeoffs includes assessments of the economics of scale of large platforms with multiple instruments relative to smaller spacecraft; the influences of current and possible future launch vehicles on payload sizes, and on-orbit assembly decisions; and the respective roles of low-Earth versus geostationary Earth orbiting systems.

Garrett, L. Bernard↗

NASA NTRS1991

Selection of representative instruments for a global change technology architecture trade study

The objectives of Task 2 of the Global Change Technology Initiative (GCTI) Architectural Trade Study were to select representative sets of instruments for making the science measurements specified in Task 1 and to identify instruments that, when flown together, form special complementary packages for measurement purposes. The list of representative instruments and their complementary relationships provide a payload manifest defined in terms of mass, power, size, viewing angles, data rates, etc. which can be used to focus spacecraft trade studies and the definition of a candidate GCTI fleet. Science requirements from Task 1 are given in tabular form. Numerous instruments are described, including visible-infrared radiometers, visible-infrared spectrometers, gas correction radiometers, active systems for Earth observation, Limb viewing instruments, visible-infrared and grating spectrometers, and microwave radiometers.

Hypes, Warren D.↗

NASA NTRS1991

Options in the global change fleet architecture provided by the presence of an EOS-A and -B

The baseline architecture of the Global Change Technology Initiative (GCTI) fleet was established by selecting and designing spacecraft and instruments to meet the science requirements developed under the task 1 effort. While attempting to meet the temporal sampling portion of the science requirements, no consideration was given to the presence of the proposed Earth Observing System (EOS) Spacecraft that would be making many of the same measurements with many of the same instruments. After establishing the GCTI baseline independent of the EOS Spacecraft; however, it is now prudent to examine the impact of the presence of the EOS Spacecraft on the GCTI fleet. A small scope, GCTI study supplement was accomplished to assess the impact. The content and results of the supplementary study are presented.

Hypes, Warren D.↗

NASA NTRS1990

Single launch lunar habitat derived from an NSTS external tank

A concept for using the spent external tank from a National Space Transportation System (NSTS) to derive a lunar habitat is described. The external tank is carried into low Earth orbit where the oxygen tank-intertank subassembly is separated from the hydrogen tank, berthed to Space Station Freedom and the subassembly outfitted as a 12-person lunar habitat using extravehicular activity (EVA) and intravehicular activity (IVA). A single launch of the NSTS orbiter can place the external tank in LEO, provide orbiter astronauts for disassembly of the external tank, and transport the required subsystem hardware for outfitting the lunar habitat. An estimate of the astronauts' EVA and IVA is provided. The liquid oxygen intertank modifications utilize existing structures and openings for man access without compromising the structural integrity of the tank. The modifications include installation of living quarters, instrumentation, and an airlock. Feasibility studies of the following additional systems include micrometeoroid and radiation protection, thermal control, environmental control and life support, and propulsion. The converted lunar habitat is designed for unmanned transport and autonomous soft landing on the lunar surface without need for site preparation. Lunar regolith is used to fill the micrometeoroid shield volume for radiation protection using a conveyer. The lunar habitat concept is considered to be feasible by the year 2000 with the concurrent development of a space transfer vehicle and a lunar lander for crew changeover and resupply.

King, Charles B.↗

NASA NTRS1990

Lunar habitat concept employing the Space Shuttle external tank

The Space Shuttle external tank, which consists of a liquid oxygen tank, an intertank structure, and a liquid hydrogen tank, is an expendable structure used for approximately 8.5 min during each launch. A concept for outfitting the liquid oxygen tank-intertank unit for a 12-person lunar habitat is described. The concept utilizes existing structures and openings for both man and equipment access without compromising the structural integrity of the tank. Living quarters, instrumentation, environmental control and life support, thermal control, and propulsion systems are installed at Space Station Freedom. The unmanned habitat is then transported to low lunar orbit and autonomously soft landed on the lunar surface. Design studies indicate that this concept is feasible by the year 2000 with concurrent development of a space transfer vehicle and manned cargo lander for crew changeover and resupply.

King, Charles B.↗

NASA NTRS1990

A survey of surface structures and subsurface developments for lunar bases

Concepts proposed for lunar-base structures and shelters include those fabricated on earth, fabricated locally using lunar materials, and developed from subsurface features. Early bases may rely on evolutionary growth using Space Station modules and nodes covered with regolith for protection against thermal and radiative stresses. Expandable/inflatable shelters used alone on the surface or in conjunction with subselene (beneath the lunar surface) features and spent portions of the Space Shuttle's fuel tanks offer early alternatives. More mature lunar bases may need larger volumes provided by erectable buildings, hybrid inflatable/rigid spheres, modular concrete buildings using locally derived cement, or larger subselene developments.

Hypes, Warren D.↗

NASA NTRS1989

Tropospheric ozone in the vicinity of the ozone hole - 1987 Airborne Antarctic Ozone Experiment

Results are presented on ozone measurements in the upper troposphere/lower stratosphere over Antarctica, obtained by NASA DC-8 aircraft during the August/September 1987 Airborne Antarctic Ozone Experiment. The ozone mixing ratios as high as several hundred ppbv were measured, but in all cases these ratios were observed in pockets of upper atmospheric air, both in the vicinity of and away from the location of the ozone hole. The background ozone values in the surrounding troposphere were typically in the range of 20-50 ppbv. Correlation of tropospheric ozone observations with the boundaries of the ozone hole differed in the course of the experiment. During the August 28 - September 2 flights, encounters with ozone-rich air were limited, and the background tropospheric ozone appeared to decrease beneath the hole. For the later flights, and as the ozone hole deepened, the ozone-rich air was frequently observed in the vicinity of the hole, and the average ozone values at the flight altitude were frequently higher than the background values.

Gregory, Gerald L.↗

NASA NTRS1988

ECLS systems for a lunar base - A baseline and some alternate concepts

A baseline ECLS system for a lunar base manned intermittently by four crewmembers and later permanently occupied by eight crewmembers has been designed. A summary of the physical characteristics for the intermittently manned and the continuously manned bases is given. Since Space Station inheritance is a key assumption in the mission models, the ECLS system components are distributed within Space Station modules and nodes. A 'core assembly' concept is then developed to meet the objectives of both phases of the ECLS system. A supplementary study is discussed which assessed tankage requirements, penalties incurred by adding subsystem redundancy and by pressurizing large surface structures, and difficulties imposed by intermittent occupancy. Alternate concepts using lunar-derived oxygen, the gravitational field as a design aid, and a city utility-type ECLS system are also discussed.

Hypes, Warren D.↗

NASA NTRS1988

The environmental control and life support system for a lunar base - What drives its design

It is noted that no single ECLSS is uniquely applicable to a mission of given crew size and duration; all mission parameters, together with details of other systems, must accordingly be factored into the lunar base ECLSS design process that is presently discussed. Experience to date with ECLSS design tasks indicates that mission planners and systems engineers should refrain from emphasizing the 'closed loop' aspects of such systems, since even the best regenerative processes will involve expendable materials that must be resupplied; resupply logistics will accordingly constitute a considerable effort of lunar base operation. Technology development status for processes and subsystems is identified as a major ECLSS design driver.

Hypes, Warren D.↗