The United States Navy's early designation for the Douglas C-47 was the R4D and this variant was the R4D-5, fitted with a ski-equipped undercarriage and JATO rocket-assisted take-off bottles under the fuselage for operation on snow and ice. Named 'Que Sera Sera' (What will be, will be), 12418 of Squadron VX-6 (Air Development Squadron Six) became the first aircraft to land at the South Pole on 31st October 1956 at 08:34 GMT.