Yes Lusaka in 1955 - now Lusaka City Airport.
I thought the words on the roof were a bit of a giveaway - I've replaced the image so that they are visible. The straight lines on the roof helped me to copy and paste areas ajacent to the letters over the top - didn't fool you though
Here's an aerial shot from 1964 - slightly different from the GE view today.
I captured this (05:07 onwards) from the following BOAC file - also shows the roof.
SH - You have control