Well, this is a little different.
It all started with the announcement of a limited number of seats from Irish airports to the East Coast of the States for as little as €69.
Norwegian Air made the announcement of the low-fare flights to a number of smaller US airports in New York, Boston and New England:
Aer Lingus seemed to find some things they didn't offer, which the Irish airline did:
No free bag?— Aer Lingus (@AerLingus) February 23, 2017
No free seat assignment?
No free meal?
Cheers, you're grand. https://t.co/aZIHqZJpJc
However the battle didn't really stop there, as Norwegian Air decided to respond:
And really, it just kept going from there:
And that's how it finished. We'll keep an eye on this one for interest.