I was in a Canadair CL44 turbo-prop freighter enroute from Lagos to Kano in the 1970's when we were struck one night.
St Elmo's fire turned the windscreen laminate into a mass of purple veins,
like a leaf, and the tips of the propellers looked like Catherine Wheels!
When we arrived at Kano and did a walk round there was a small hole
in the skin near the base of the fin. Apart from that the aircraft was
fully serviceable, and it did not affect the integrity of the pressure hull.
The turbulence was interesting though!!