1971 - US Army Ecology Test of Terrain Deterioration

These evaluations prove that a lesser size hovercraft would have even less effect on the environment!

Ecology

CRREL has determined the ecological impact of summer SEV operations over soft, wet tundra in Northern Alaska, During the summer 1971 series of SK-5 ACV field tests at Barrow, Alaska, a CRREL ecological team observed that the severity of damage to tundra vegetation depends on the amount of traffic and is due primarily to skirt contact. Follow-up observations were made in following years (summers of 1972 and 1973) to assess recovery of the tundra. Also in the summer of 1973, utilizing a SEV skirt/cushion simulator, CRREL obtained quantitative data on the ecological impact of various cushion pressures, air temperatures, air mass flow rates, and skirt drag conditions. These data were subsequently used under joint US Army Corps of Engineers/ARPA/NSRDC funding to develop and validate computerized techniques to predict and assess future ecological impact. In accomplishing this task, CRREL drew upon the significant technical expertise in quantitative ecological assessment and environmental modeling developed by the National Science Foundations International Biological Program.

It was concluded from these studies that the impact of Arctic SEV operation is substantially less than any other form of surface transportation, the resulting tundra damage is localized, relatively minor, and can be expected (except in heavily trafficked areas) to fully recover within 3 to 10 years, and that operations over surfaces other than tundra are not likely to show any significantly measurable ecological impact.

TECHNOLOGY DEVELOPMENTS -- OVERALL TECHNICAL APPROACH

One of the first tasks undertaken following the formation of the Arctic SEV Program Office (ASEVPO) was to define in detail those problems unique to an SEV intended to operate in the Arctic. To this end, the following was undertaken:

1. Field trials of an SK-5 air cushion vehicle.
2. Parametric studies in specific areas to identify problems and develop analytical or experimental tools and techniques towards their solutions. (This was a contracted effort that was supplemented by the efforts of various technical departments of the NSRDC and by information exchanges with the Navy's Advanced Amphibious Landing Craft (AALC), Surface Effect Ships (SES) and Hydrofoil Program Offices.)

Following these parametric studies and based on mission analyses, specific point designs for Arctic SEVs in the 150-ton and 500-ton weight class were developed to permit, within the remaining program time and funding, the maximum technology development, design detail and confidence in performance projections for Arctic SEVs of sufficient size to viably perform useful Arctic missions.

Figure - US Army SK-5 Air Cushion Vehicle During Snow and Ice Interaction Tests at Houghton, Michigan