UK regional operator Flybe Group's proposed Irish division would have the right to use the Aer Lingus brand for up to three years following its creation.
The new operating company will be named Flybe Ireland and serve 34 European destinations - a total of 43 routes - from two bases in Dublin and Cork.
Flybe Group says its UK operation already serves around half of these.
If approved by Flybe Group shareholders the new Irish operation would start services at the beginning of the winter season around October 2013.
As part of the agreement with Ryanair to create Flybe Ireland, the company will have the right to use the Aer Lingus brand for a limited time.
"This will allow it to develop its own brand position in Ireland during a realistic transition period," says Flybe.
Flybe Ireland will commit to operating agreed frequencies on its routes but have the freedom to axe a "certain number of routes" per year, it adds, while maintaining "stable capacity" in the Irish market.
Exceeding this route termination threshold would incur a penalty.
Ryanair's bid for Aer Lingus - on which the creation of Flybe Ireland depends - is undergoing European Commission scrutiny and a decision on the proposed takeover is due on 6 March.
If Ryanair proceeds with the acquisition, the Flybe arrangement would close around mid-May and details sent to Flybe shareholders in August.