McMurdo Station Pegasus Field

The primary reason for closure was runway degradation due to environmental factors. The 'blue-ice' runway was experiencing excessive surface melting during the peak summer months (December and January). This was caused by a combination of rising ambient temperatures and the accumulation of dark volcanic dust and sediment from nearby Black Island and Mount Erebus. The dark material lowered the ice's albedo (reflectivity), causing it to absorb more solar radiation and melt faster. This created an unstable, slushy surface that was increasingly unsafe for the heavy, high-pressure tires of wheeled aircraft like the C-17 Globemaster III, posing significant operational risks.

The site of the former Pegasus Field is no longer maintained or certified as an active runway. The area is now used as a logistical support and staging area by the US Antarctic Program. Its large, flat, and stable surface on the ice shelf is utilized for storing equipment, containers, and vehicles. The original 'Pegasus' C-121 aircraft wreckage remains at the site and serves as a historical point of interest.

Pegasus Field was a critical logistical hub for the United States Antarctic Program (USAP) for over two decades, from its opening in 1992. Its key significance was its status as a year-round, hard-surface runway capable of handling heavy, wheeled intercontinental aircraft. Unlike the annual Sea Ice Runway (usable only in early summer before the sea ice breaks up) and Williams Field (primarily for ski-equipped aircraft), Pegasus's durable blue-ice surface provided reliable access for large cargo planes like the C-141 Starlifter and its successor, the C-17 Globemaster III. This capability was vital for transporting personnel and massive amounts of cargo and scientific equipment to McMurdo Station and for the resupply of the Amundsen-Scott South Pole Station. The field was famously named after 'Pegasus,' a C-121 Lockheed Constellation that crashed during a storm on October 8, 1970, without fatalities; its well-preserved wreckage remains a prominent landmark near the site.

There are no plans or prospects for reopening Pegasus Field. It was permanently replaced by the nearby Phoenix Airfield (ICAO: NZFX), which became fully operational for the 2017-2018 season. The Phoenix runway was constructed using an innovative technique of compacting and sintering deep layers of snow, creating a durable runway that is more resistant to the melting issues that plagued Pegasus. The significant investment in constructing and maintaining the new, more resilient Phoenix Airfield, combined with the persistent and worsening environmental challenges at the Pegasus site, makes its reactivation both unnecessary and impractical.