Fewer flights were on time and consumer complaints about airlines rose in May, according to the latest government figures .
The Transportation Department said Friday that 79.1 per cent of flights on the 12 largest U.S. airlines arrived on time in May, down from 83.4 per cent in May 2016.
Hawaiian Airlines had the best rating, followed by a closely bunched group of Delta, Alaska, SkyWest and United. Virgin America was last.
There were 27 ground delays of more than three hours, which could subject the airlines to fines. Most were on a single stormy day in Philadelphia.
The Transportation Department logged 1,262 consumer complaints about the U.S. airlines, up 54 per cent from May 2016. However, that's a tiny fraction of the millions of travellers. Most
who complain do so directly to the airline.