Most notably in Europe there were significant delays and capacity constraints at key airports.
According to Eurocontrol, there was a 33% increase in arrival delays compared with 2019, reaching 16.9 minutes per flight on average. Peak periods easily exceeded that average. Departure punctuality was below 50% at the beginning of July and rarely rose above 60% for the next two months. The difficulties were such that 6.9% of 2022 scheduled flights didn’t take off at all.
The bad news is that the northern hemisphere 2023 summer season could be even worse.
A challenging summer is ahead of us, read more: https://airlines.iata.org/analysis/european-2023-delays-must-be-tackled-now