STORY: Australia's biggest airline Qantas Airways issued an apology to its frequent flyers on Monday, over a slew of operational issues in recent months.

A rebound in travel demand came with a rise in delays, cancellations, lost baggage and staffing issues.

To compensate, its frequent flyer members will be receiving vouchers, loyalty status extensions and lounge passes.

On Monday, they also received an email and video message from long-time chief executive Alan Joyce.

"Two years on the ground was tough on everyone, and we know the return to flying hasn't all gone smoothly. Over the past few months, too many of you have had flights delayed, flights cancelled or bags misplaced. There are good reasons why but when it comes to what you expect from Qantas, it's not good enough."

"On behalf of the national carrier, I want to apologize, and assure you that we're working hard to get back to our best."

The carrier said it was currently dealing with high levels of staff sick leave, and an industry-wide labor shortage.

That's after cutting thousands of jobs and putting most of its staff on leave without pay for long periods, owing to the global health crisis.

Despite that, Qantas said it had already hired 1,500 new staff since April - part of its new initiatives to improve operations.

The airline is due to release its full-year financial results on Thursday.