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The U.S. Antarctic Program is conducting a proof-of-concept traverse to haul heavy cargo 1600 km from McMurdo Station to South Pole Station. During the 2003-04 season (year two), the tractor-trains experienced poor mobility over undisturbed snow on the Ross Ice Shelf. despite relatively low sled ski pressures and encouraging results of pre-departure tests conducted on the McMurdo Ice Shelf. To understand why, we conducted expedient mobility tests, snow-strength measurements, and snow-pit studies along 250-km of route as the traverse returned to McMurdo. The key phenomenon causing train immobility appears to be traction-slip-resistance feedback resulting from the sled skis riding in the ruts made by the towing tractors. We measured much lower towing resistance when the same sleds were towed over undisturbed snow outside of the tractor ruts. Large pitch and roll motions and consequently large resistance peaks, also occurred when several sleds were towed in series. The role of snow strength was more difficult to assess. Hard sastrugi caused severe motions and sled breakdowns. Decreasing average strength towards the center of the Ross Ice Shelf agreed with qualitatively worsening mobility but quantitative results were inconclusive. Also, increased measured strength on the previously traveled trail was insufficient to account for improved mobility of the returning fleet. The year-two results formed the basis for recommendations to improve fleet mobility for year three: tow fuel sleds in 2 x 2 configurations, rather than four in-line; increase the gauge of the other sleds to place the skis outside of the tractor ruts; increase ski area and alter nose shape for the fuel sleds; and install instrumentation to monitor towing forces, sled sinkage, and snow strength along the entire route. The U.S. Antarctic Program adopted these recommendations.

Tbc Naval Postgraduate School's Small Robotic Technology (SMART) Initiative is an ongoing research effort within the Combat Systems Science and Technology Curriculum that engages in forward-looking applications of small robotic technology for military employment. The goal of the program is to develop a multipurpose robotic platform that is capable of hosting varied sensor packages for military research. This thesis successfully modified a Foster Miller Learning tracked vehicle: Payload volume was increased to allow for ease of systems testing and access while incorporating a method for deploying varied sensor modules on a towed sled. Original micro-controller hardware has been replaced with a COTS system that allowed for simplified interfacing with a Honeywell digital compass and a Motorola G.P.S. card. Communications with the Robot were provided through the internet via a modem. A control interface for use on a personal computer was implemented by creating a JAVA application; the control interface has also been converted to a JAVA applet that the Robot is capable of downloading to a user via a web interface. Follow on research will fully integrate the Robot with a variety of sensor packages including a synthetic array seismic sonar, visual and infrared devices and chemical detection devices., "The original document contains color images"

The slingatron mass accelerator is described for several track configurations (shapes), and numerical simulations of this accelerating mass traversing a given track configuration are presented. The sled is modeled as a point mass that interacts with the slingatron track using both a conventional and a new empirical velocity dependent friction law. The closed loop circular slingatron was found to produce high maximum sled velocities provided the gyration angular speed is always increasing. In contrast several spiral shaped slingatron tracks reveal that high maximum sled velocities are obtainable with the gyration speed held constant. In fact a slingatron constructed out of semi-circles is shown capable of generating high velocity sleds in such a way that no initial sled injection is necessary. Choosing the proper initial gyration phase with an empirically determined friction model allows the mass sled to gain ever-increasing velocities when placed in a semi-circle slingatron. The sled bearing pressure and its total acceleration are examined and presented.

Core-M has undertaken to design, develop and produce proof of concept models of control and data acquisition system for the LSTAT sled. The architecture for such a system is based on Core-M's unique modular electronic units that are individually programmable for any desired application. Each module has its own memory buffer area to assure real time acquisition and processing of the data collected. The units communicate with each other through 12C protocol, which requires only two wires. This unique approach makes it possible to realize low weight, low power, easy tQ implement system for LSTAT sled project.

This report describes the development and field verification of a new hydrographic surveying system for fluid mud channels. A rapid, precise, and accurate survey system for fluid mud channels was required under this work effort. At the onset of the work, European experience was studied. Although the system was not designed to operate like the fluid mud evaluation systems used in Europe, application of an intrusive gauge was considered to be the only reliable depth evaluation approach. The new fluid mud surveying system includes a towable sled that provides prima facie evidence of any material resistance encountered while returning a firm bottom level. The sled system has been field tested in three fluid mud channels along the Gulf of Mexico that have a history of fluid mud channel problems. The system goals of developing a rapid and accurate fluid mud channel depth surveying system were met by the sled., Dredging Research Program.

The goal of this project was to develop a horizontal impact sled test laboratory for the National Institute for Aviation Research (NIAR) at Wichita State University to effectively serve the aviation industry relative to aircraft seat performance as well as other aircraft components. The fundamental goal was achieved in the fall of 1992, and the ensuing period has been spent testing with at least five commercial clients, three of which were FAA observed certification tests. Aircraft, Rotor craft, Crashworthiness, Impact sled, Seats.

Describes procedures for using either a fixed or portable ballistic rail to launch dynamically-detonated munitions.... Detonator, Rocket sled, Ballistic rail, Explosive train, Munitions.

During the past several years, the Federal Aviation Regulations (FAR) have been significantly modified with respect to seat/restraint system strength, attachment of seats to the aircraft structure, and the means by which they are to be evaluated. Aircraft accident data, human tolerance levels, and aircraft structural characteristics have been considered in the development of these new standards. Dynamic testing is now required for seats to be installed in general aviation aircraft, transport category aircraft, and rotorcraft. Performance criteria are similar to those specified by the Federal Motor Vehicle Safety Standards for automobiles but also include a limit on pelvic force, in order to prevent spinal injuries which may be caused by the vertical component of impact force. A category of aircraft that has not as yet been affected by the rule modifications is the commuter type aircraft, which seats 10 to 19 passengers. Since this airplane is closer in size to general aviation aircraft than to large transports, it is also covered by FAR Part 23. The Federal Aviation Administration is currently involved in the conduct of a test program addressing commuter aircraft occupant crash safety. In support of this effort, a research program the includes full-scale aircraft drop tests, sled tests of seats, and computer simulations is being conducted. This report describes the use of the SOM-LA (Seat/Occupant Model - Light Aircraft) program in modeling three commuter aircraft seats. The predicted response of the seats to a potential set of test conditions is described. Crashworthiness, Aircraft seats, Restraint systems, Computer simulation.

This technical note presents an intermediate evaluation of a fluid mud survey system with respect to operability, practicability, and repeatability based on field tests conducted at Calcasieu River, Louisiana) Sabine River, Texas; and Gulfport Harbor, Mississippi, entrance channels from 1989 to 1991. Also included are the conceptual and mechanical design of the towed sled and a description of the fluid mud survey system components.

This annual report covers the mathematical analysis and computer-related effort supplied by the originator in support of the Joint Army/Navy Air Crew Impact Injury Prevention Program. An important part of this effort was the analysis, coding and debugging of an EKG Wave Form Recognition and Analysis Program. The mathematical analysis, coding and debugging of three other computer programs connected with the Horizontal Accelerator data processing effort were also completed during this period. These three programs are: the 3-D Transformation Program, the Angular Velocity Peak Detection and Regression Analysis Program and the Runge-Kutta 3-D Tracking Program.

This annual report covers the mathematical analysis and computer-related effort supplied by the originator in support of the Joint Army/Navy Air Crew Impact Injury Prevention Program and the Navy Bureau of Medicine Medical Contingency Requirements Program. The mathematical analysis, coding and debugging were performed for the following programs connected with the Horizontal Accelerator data processing effort: the X-Ray Anthropometry Program, Conversion/Scaling Program, the Random Access Program, the Horizontal Sled Test Report Program, the Regression Analysis of Peak Rotational Acceleration and Velocity program, the Principal Component Analysis Program, the Spectral Analysis Program, the Filter Program for Horizontal Sled Accelerometer Data, and other programming tasks. A system was devised to perform Blood Chemistry Data Processing. A number of tasks in the Management Information area were also performed. For the Navy Bureau of Medicine a mathematical method was devised to calculate the Navy Medical Contingency Requirements in beds and medical personnel for any desired time periods and areas.

An extensive evaluation was conducted to determine the capability of the HH-3F helicopter to tow the Fast Surface Delivery (FSD) System. The aircraft flying qualities, aircraft response to simulated emergencies, Automatic Flight Control System, and the simplicity and reliability of the tow equipment enhance the ability of the HH-3F helicopter to fulfill the requirements of the U.S. Coast Guard tow mission. Mission limitations are imposed by the low power margin at high gross weights in the low speed tow regime. Inefficient transmission oil cooler operation limits the amount of time allowed in a downwind tow condition. Further testing is recommended to determine pilot fatigue limitations due to unusual aircraft attitudes during tow operations. Also, additional testing is necessary to determine the effects of higher sea states on the aircraft and FSD combination. Within the scope of this evaluation, the HH-3F helicopter and FSD tow combination is satisfactory for the U.S. Coast Guard operational tow mission.

The current state of ejection seat/sled testing employs an Aydin/ Vector Co. pulse code modulation/telemetry instrumentation package. While this system meets all channel/data rate requirements and has proven itself in field testing, some major deficiencies exist. Data turnaround is one drawback; up to several weeks are normally required to process and print out the results from any sled shot. A second major deficiency is the amount of data dropout that can occur. In an ejection seat test, orientation of the skull antenna or misalignment of sending and receiving antennas can result in loss of data. Current technology in data storage media and high-speed controllers provides backup mode for data integrity and also permits faster data reduction. This paper summarizes an electrical/mechanical packaging design of a software controlled, nonvolatile data recording system which uses 8 megabits of bubble memory to provide 24 sec of data storage in parallel to the PCM/TM transmission. Preliminary laboratory bench testing of the Solid State Memory Instrumentation (SSMI) Recorder indicates that the bubble memory can withstand the high vibration g loads (20 Gs up to 2000 Hz) and environmental temperatures (85 C) encountered in ejection seat testing. Laboratory shock testing (ejection seat trainer) to 5 Gs has also been successful along with tower testing at the Naval Air Development Center to 25 Gs. Keywords: Nonvolatile magnetic bubble memory; Anthropomorphic dummies; Sled ejection seat testing.

X&GXEGCC: GENERAL DATA ON CONTEMPORARY FACILITIES FOR THE RESCUE OF AN AIRCRAFT CREW UNDER EMERGENCY CONDITIONS; HIGH ALTITUDE AND PROTECTIVE EQUIPMENT; TESTING OF SURVIVAL AND RESCUE EQUIPMENT., Unedited rough draft trans. of mono. Sovremennye Sredstva Avariinogo Pokidaniya Samoleta, Moscow, 1961, p. 5-23, 307-431.

A family of wanigans was developed to provide portable shelters for use in polar regions. These wanigans are of two types: sled wanigans are mounted on cargo sleds for trail use; portable camp wanigans are built with a skid system for limited movement around a camp or work area. All of the wanigans are 20 feet long and 8 feet high. Both types are made in standard 8- foot widths for assembled air shipment, and in extra-wide 10-foot widths for flexibility in interior arrangement. Standard accessories for the wanigans ARE: a heating and ventilating system, an electrical harness, and a sidemounted fuel tank. This technical note contains the specifications for the wanigans presented in NCEL R-309, Polar Structures - NCEL Family of Wanigans.

The need for adequate shelter for maintenance and repair of construction and other equipment in pioneer polar camps resulted in the development of a packaged maintenance shelter. The shelter is a canvas-covered, aluminum-frame structure. It is skid-mounted for easy portability around a work area. The 20- by 24-foot shelter is adequate for the repair and maintenance of equipment as large as a Size 2 snow tractor and a Size 4 standard tractor. A standard NCEL portable wanigan was outfitted with shop equipment and tools as a companion piece for the shelter. A prototype shelter was evaluated on the Ross Ice Shelf in Antarctica. It was concluded from the test that the shelter and its outfitting is well suited for the maintenance and repair of equipment at pioneer polar camps and that it should be included as a facility for such camps.