Entry, Descent, and Landing for Human Mars Missions.

imagesCA18WE00One of the most challenging aspects of a human mission to Mars is landing safely on the Martian surface. Mars has such low atmospheric density that decelerating large masses (tens of metric tons) requires methods that have not yet been demonstrated, and are not yet planned in future Mars missions. To identify the most promising options for Mars entry, descent, and landing, and to plan development of the needed technologies, NASA’s Human Architecture Team (HAT) has refined candidate methods for emplacing needed elements of the human Mars exploration architecture (such as ascent vehicles and habitats) on the Mars surface. This paper explains the detailed, optimized simulations that have been developed to define the mass needed at Mars arrival to accomplish the entry, descent, and landing functions. Based on previous work, technology options for hypersonic deceleration include rigid, mid-L/D (lift-to-drag ratio) aeroshells, and inflatable aerodynamic decelerators (IADs). The hypersonic IADs, or HIADs, are about 20% less massive than the rigid vehicles, but both have their technology development challenges. For the supersonic regime, supersonic retropropulsion (SRP) is an attractive option, since a propulsive stage must be carried for terminal descent and can be ignited at higher speeds. The use of SRP eliminates the need for an additional deceleration system, but SRP is at a low Technology Readiness Level (TRL) in that the interacting plumes are not well-characterized, and their effect on vehicle stability has not been studied, to date. These architecture-level assessments have been used to define the key performance parameters and a technology development strategy for achieving the challenging mission of landing large payloads on Mars.

Personal Author A. M. DwyerCianciolo M. M. Munk

Food Code 2013 (on CD-ROM) (powered by Flipviewer).

imagesThe Food Drug Administration (FDA) Food Code 2013 contains the latest FDA advice on preventing foodborne disease in food outlets including restaurants, grocery stores, and food vending operations. It consists of model requirements for safeguarding public health and ensuring that food offered to the consumer is safe, unadulterated, and honestly presented. The model is adopted by local, state, and federal governmental jurisdictions for administration by the various governmental units within each jurisdiction that have been delegated compliance responsibilities.

For more informatiion please go to: http://www.ntis.gov/search/product.aspx?ABBR=PB2014500018

or call 1-800-553-6847 (www.ntis.gov)

Personal Author N/A

Launch and Assembly Reliability Analysis for Mars Human Space Exploration Missions

imagesCA18WE00NASA’s long-range goal is focused upon human exploration of Mars. Missions to Mars will require campaigns of multiple launches to assemble Mars Transfer Vehicles in Earth orbit. Launch campaigns are subject to delays, launch vehicles can fail to place their payloads into the required orbit, and spacecraft may fail during the assembly process or while loitering prior to the Trans-Mars Injection (TMI) burn. Additionally, missions to Mars have constrained departure windows lasting approximately sixty days that repeat approximately every two years. Ensuring high reliability of launching and assembling all required elements in time to support the TMI window will be a key enabler to mission success. This paper describes an integrated methodology for analyzing and improving the reliability of the launch and assembly campaign phase. A discrete event simulation involves several pertinent risk factors including, but not limited to: manufacturing completion; transportation; ground processing; launch countdown; ascent; rendezvous and docking, assembly, and orbital operations leading up to TMI. The model accommodates varying numbers of launches, including the potential for spare launches. Having a spare launch capability provides significant improvement to mission success. For more

info please go to:  http://www.ntis.gov/search/product.aspx?ABBR=N20130012764 

Personal Author C. Stromgren G. R. Cates K. E. Goodliff W. M. Cirillo

Bureau of Mines Publications and Journal Articles 1910-1996

The United States Bureau of Mines of the Department of the Interior was established in 1910 by the Department of the Interior and abolished on March 30, 1996.

NTIS maintains the entire collection of the Bureau’s publications, some 5,000 documents. This page lists the printed indexes that are available to locate these publications as well as providing a search box to locate publications in the NTIS collection.

The Bureau was established to conduct inquiries and scientific and technological investigations on mining and the preparation, treatment, and use of mineral substances; to promote health and safety in the mineral industries; to conserve material resources; to promote economic development; to increase efficiency in the mining, metallurgical, quarrying, and other mineral industries; and to inquire into the economic conditions affecting those industries.  To conduct your search of our

collection please go to:  http://www.ntis.gov/products/bom.aspx