Mount Pleasant Airport / RAF Mount Pleasant lies in the high southern latitudes at 51.82° S, 58.45° W, on Atlantic/Stanley time (UTC-3).
Mount Pleasant Airport / RAF Mount Pleasant has 2 runways. The longest, 10/28, measures 8,497 ft by 150 ft, which puts the field in the widebody capable category: twin-aisle aircraft can use it, and narrowbodies have length to spare. The surface is asphalt. Both are lit for night operations.
Runway 10/28 is aligned roughly east/west, which is the clearest hint you get about the prevailing wind here: runways are built to face the wind that blows most often, because aircraft take off and land into it. With 2 runways across 2 different headings, crews can pick whichever best suits the wind.
The runways are not interchangeable. 05/23 is 5,003 ft against 10/28's 8,497 ft, a difference of 3,494 ft, so the shorter one generally takes regional traffic while the longer handles anything heavy.