The best and worst airlines and airports of 2018, according to AirHelp

Last summer, on a bucket list trip through Southern Africa, I took a total of six flights with South African Airways. On the first one, a 15-hour trip from New York's JFK Airport to Johannesburg, my air vent and seat-back screens were both broken. On my next five flights, the situation was only marginally better.

Within a week of my return, a customer…