Compacted-snow Runways in Antarctica
Compacted-snow Runways in Antarctica

Author: G. E. Sherwood

Publisher:

Published: 1967

Total Pages: 26

ISBN-13:

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Techniques and equipment have been developed to utilize clean, undisturbed snow as a building material for emergency and temporary roads, runways, and skiways in polar regions. However, these routes are often needed in areas where the snow is contaminated. During Deep Freeze 65, a compacted-snow runway was constructed in an area of contaminated snow near McMurdo, Antarctica. The area had been contaminated by oil spillage, soot, and debris from previous operations. Physical property tests were conducted on the compacted snow near the end of Deep Freeze 65 and during Deep Freeze 66. It was concluded that contaminated snow can be processed to produce load-carrying material capable of supporting C-130 aircraft and other heavy loads at temperatures below 20F; however, because of the extra work involved to clear and process such snow, its marginal load-carrying capabilities at temperatures above 20F, and the possibility of low-strength areas, its use is not recommended where clean snow is available. New processing techniques resulted in improved quality control of compacted snow, and it was recommended that effort be continued to improve processing techniques. (Author).

Compacted-snow Runways in Antarctica, Deep Freeze 61-64 Trials
Compacted-snow Runways in Antarctica, Deep Freeze 61-64 Trials

Author: R. C Coffin (Jr)

Publisher:

Published: 1966

Total Pages: 51

ISBN-13:

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In Deep Freeze 61, NCEL provided technical guidance to a Navy snow- compaction team investigating the practicability of building roads on snow- covered sea ice over McMurdo Sound and runways on the deep snow cover of the Ross Ice Shelf adjacent to McMurdo Station. These investigations and trials continued through Deep Freeze 64. This work was directed toward the development of a layered, compacted-snow runway on deep snow which would support aircraft weighing up to 155,000 pounds with tires on the main wheels inflated to 135 psi; it was only partially successful. During the trials, there were intermittent areas of compacted snow capable of supporting aircraft weighing up to 100,000 pounds with main tires inflated to 90 psi, but low-strength areas prevented takeoffs and landings with aircraft weighing over 25,000 pounds with main tires inflated to 60 psi. New processing and elevating equipment introduced in the Deep Freeze 64 trials showed considerable promise of producing dense, uniform, high -strength, elevated areas of compacted snow. It was concluded that the trials should continue in Deep Freeze 65 to explore the capabilities of this equipment.

Testing of a Compacted Snow Runway (U)
Testing of a Compacted Snow Runway (U)

Author: James Arthur Bender

Publisher:

Published: 1956

Total Pages: 38

ISBN-13:

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The processing of the snow for the runway, by modified pulvimixers using heat, was started on 6 July and completely finished by 1 September. Successful landings on the 200 x 10,000 ft strip were made by C-47, C-54, and C-124 type aircraft. The conclusion that the strip could support these aircraft and the decision to land the planes were based on the laboratory testing. This report describes the methods and techniques used in testing a snow runway built on deep snow, and gives suggested requirements of a snow runway to support various type aircraft. It is not intended as a report on the operational aspects of making such a runway, nor as a critique on the techniques used. Also, it should be realized that this represents the beginning of a long-range program and that additional theoretical work and field work are still necessary. (Author).

Stress Analysis of the Phoenix Compacted Snow Runway to Support Wheeled Aircraft
Stress Analysis of the Phoenix Compacted Snow Runway to Support Wheeled Aircraft

Author: Ariana M. Sopher

Publisher:

Published: 2017

Total Pages: 12

ISBN-13:

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Landing wheeled aircraft on snow runways is uncommon and minimally documented. This report describes the modeling used to evaluate design and construction of the new compacted-snow Phoenix runway in Antarctica for the first wheeled C17 aircraft landing. Snow density from the target design and snow density of the as-built Phoenix runway structure were used to determine basic elastic parameters for use in layered elastic analysis formulation (LEAF). LEAF is part of a software package developed by the Federal Aviation Administration (FAA) that allows for forward calculation of runway stress, strain, displacement, and associated principal stress and strain based on design aircraft loading. Stress responses for the Phoenix runway were modeled for the C17, A319, and B757 aircraft. Two construction vehicles were also modeled for comparison. Results show the comparison of the stress profiles and effect of subgrade stiffness on stresses in the layers just above the subgrade. This is the first time the model was used for a snow runway and it provided valuable insight for design, construction and runway performance for the first landing of the C17 on compacted snow. The model is flexible enough for simulating additional aircraft that might use the runway in the future. The successful construction and use of the new compacted-snow Phoenix runway is significant and demonstrates the heaviest wheeled aircraft (C17) operating on a compacted snow runway, ever.

Compacted-snow Runways in Antarctica
Compacted-snow Runways in Antarctica

Author: E. H Moser (Jr)

Publisher:

Published: 1966

Total Pages: 81

ISBN-13:

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Snow-compaction investigations were conducted on the Ross Ice Shelf adjacent to McMurdo Sound during Deep Freeze 65 following investigations made during Deep Freeze 61 through Deep Freeze 64. A 150-by 6,000-foot runway was constructed by adding a 16-inch layer of compacted snow over an existing layer. Construction was completed on 24 November 1964 and the runway was maintained and repaired for aircraft tests until 14 February 1965. Snowplow carriers used in clearing the runway of drift snow greatly reduced the time required for this operation over previous methods using a snowplane. A 6 by 6 truck-tractor with high-flotation tires served as a prime mover for maintenance equipment, and resulted in large savings in time over use of a size 2 snow tractor. This wheeled vehicle also eliminated damage to the runway surface caused by track vehicles. The runway was tested early in the season by a 25,000-pound C-47J aircraft with tire inflation pressure of 60 psi; it was tested five times at approximately 2-week intervals by an LC-130F aircraft weighing from 90,000 to 135,000 pounds with tire inflation pressures of 85 to 95 psi. During the first LC-130F tests, intermittent failures occurred in the DF-65 layer of compacted snow due to misses between lanes of snow processed by the mixers and seams of unprocessed snow between the DF-64 and DF-65 layers.

Design Criteria, for Snow Runways
Design Criteria, for Snow Runways

Author: Gunars Abele

Publisher:

Published: 1968

Total Pages: 36

ISBN-13:

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The physical characteristics of snow and those processes of metamorphism which contribute to its strength are important considerations in planning the construction of compacted snow runways. Two distinct temperature-dependent processes affect the physical properties of snow: sintering and strength increase with decreasing temperature. The rate of strength increase and the ultimate strength of snow may be greatly increased by mechanical agitation or depth processing followed immediately by surface compaction. Leveling to produce a smooth surface for aircraft is also necessary. Various combinations of processing and compaction are required depending on the size of aircraft to be operated on the runway. After construction is completed, the natural process of sintering or strengthening must be allowed to proceed for some time before aircraft operations can be initiated. The mechanical properties of processed snow have been correlated with its wheel-load supporting capacity. The correlation shows the effect of such parameters as wheel load, tire contact pressure, and repetitive wheel coverages on the required hardness or strength of a compacted snow layer. Strength profiles which can be expected from certain snow processing and compaction procedures are shown and compared with required strength profiles for various types of wheeled vehicles and aircraft. The purpose of this study was to combine the knowledge gained from fundamental research in the processes of sintering with methods and procedures developed by engineers for using snow as a construction material. (Author).