Aer Lingus expects to see a far bigger reduction in flights this summer than it had previously predicted.
Stark forecasts for June and July - contained in briefing material seen by the Sunday Independent - were revealed to union leaders by airline management at one of a number of crisis briefings.
The airline had prepared a schedule for June that would see it fly 15pc of its normal flights, but the "realistic view is now closer to 5pc". The "best case" for July had been a less than 20pc schedule, but it would now be "significantly lower" than that.
The lower expectations reflect a deepening crisis for the aviation sector.
Union officials were warned that there was a need to "stop the silly stuff" with regard to work practices and told there was a "need to work sensibly and appropriately to the challenging new reality", said the briefing materials.
It was reported on Friday that Aer Lingus would seek 900 redundancies, while Ryanair warned of 3,000 job cuts.
Following the reports, Aer Lingus management and unions held a further teleconference. Union officials later warned in a memo that "management confirmed that a detailed examination was now under way across all parts of Aer Lingus on what needed to be done to respond to the developing situation".
"They also indicated that they would require some work practice change, however they did not supply any specific information," it said.
Plans outlined in other documents seen by this newspaper for other airlines in the IAG group - of which Aer Lingus is a part - showed that major outsourcing of ground-handling operations was already part of crisis recovery plans at IAG.
But Aer Lingus declined to comment as to whether plans by its IAG sister airline British Airways to carry out extensive outsourcing at London Heathrow would be replicated at Dublin.
A detailed 10-page plan sent by BA's Heathrow director to the Unite trade union, seen by the Sunday Independent, said that "a number of activities are not core to the Heathrow operation and can be more efficiently and flexibly provided by a third-party supplier (not yet identified)".
Functions earmarked for outsourcing included flight management, load control, ticketing, equipment services, transatlantic gate teams and baggage tracing - all areas staffed directly by Aer Lingus employees in Dublin.
Aer Lingus is in the process of outsourcing its Dublin catering operation to Dubai airport services giant DNATA, but has long insisted it would not outsource other ground-handling functions.
In briefings, Aer Lingus management told Irish Congress of Trade Union officials that revenue for 2020 was "substantially down" and "refunds are also driving cash out of the business".
It warned of further reductions in pay and leave allocations, as well as lay-offs and there was "a need to consider lasting changes as more clarity on 2021 emerges".
Union officials were warned that the level of funding for the terms of voluntary redundancy was "unclear".
An Aer Lingus spokeswoman said the airline was "continuing to communicate directly with our employees and engage with their representative bodies".