Originally Posted by
fumje
I think "technical issue" may be sort of a red herring, in that they code crew duty hour limits as a technical issue.
More than one thing can happen on a single flight.
When a pilot gets sick on a layover on a long haul flight they will fly a shorter leg with the remaining pilots and do a crew swap. If the pilots enter a write up for something as simple as windshield requiring cleaning then the flight had a technical issue, too. If the technical impacts the turn time at the recrew stop then it will make it into the delay codes.