If you thought flight delays had been worse over the past year, you're right.

Departures and arrivals were less likely to be on time, with Tiger the worst offender before its grounding. Qantas, on the other hand, was most likely to be punctual, according to figures up to the end of June.

Qantas flights departed and arrived on schedule 83 percent of the time. Virgin was next (79 percent departures, 78 percent arrivals), followed by Jetstar (77 percent arrivals/departures) and Tiger (65.9 percent).

Punctuality across Australian airlines last financial year fell 5 percent to 80 percent on average.

The Bureau of Infrastructure, Transport and Regional Economics blamed cyclones and the Chilean ash cloud in June, which grounded airlines.

The route with most cancellations (3 percent) was the also busiest sector, Melbourne-Sydney. Tiger had the worst cancellation record of the major airlines at 3 percent, double the rate of Qantas and Jetstar.

It was also least likely to be on time at Melbourne airport, with just 66 percent of departures and 62 percent of arrivals within the stipulated window of 15 minutes of schedule.

When Tiger took off again last week, chief Tony Davis emphasised it was committed to improving reliability, along with being safe and affordable.

A Tiger spokeswoman yesterday said flights had been on time since it returned to the air: "All airlines experience disruptions from time to time. Tiger Airways works hard to keep them to a minimum."

The figures came as Qantas assesses the impact of one-hour strikes due to start next week as engineers step up an industrial campaign.

The 1,600 engineers at Qantas sites nationwide will take turns to refuse to work for the first hour of shifts.