> I agree that 5% efficiency justifies widespread adoption, but that didn’t require much more than a few hours of maintenance to set wingtips up. Retrofitting

> I agree that 5% efficiency justifies widespread adoption, but that didn’t require much more than a few hours of maintenance to set wingtips up. Retrofitting winglets on an airliner costs a million+ upfront and grounds the plane for a week. It’s not to the level of buying a new plane, but this is not a few hours work on the tarmac between two flights, they’re not airfoils off of wish you glue onto your rust bucket.