Wings make very comfy beds I'm told.
Yes, and they come with complementary fans.
sounds like" culleen ar an eitleán
Shouldn't it be "Codlaím ar an t-eitleán"?
No. The preposition means that the noun is now in the dative rather than nominative, and the rules for initial mutation are different.
"I sleep on the plane" is not okay, apparently.
nvd elsewhere "plane" is fine....