Ryanair boss Michael O'Leary has said fares will fall by 20% in five years and by 40% in ten years on the back of its new €17bn deal with Boeing.
Mr O'Leary made his comments at Dublin Airport as the airline took delivery of its latest 737-800, the first of 180 similar planes worth €12.4bn.
The plane is not part of the €17bn Boeing deal announced on Monday.
Mr O'Leary also dismissed Dublin Airport Authority's criticism of proposals to cut airport charges.
He said there was no justification for any more "madcap" capital expenditure and he said he did not want a refurbishment of Terminal One.
The Commission for Aviation Regulation has indicated in a draft report that it wants to cut airport charges by 22% over five years.
The DAA has criticised the proposal as misguided and has said it will cause stagnation in growth at the airport.
A final decision will be made at the end of this month.
