Delta 747-400 might be scrapped after encountering hailstorm in flight.

[Zimme83]

Pressurized planes have a limited lifespan due to fatigue in the fuselage due to the pressurized cabin expanding and stretching the fuselage when flying on high alts. A lot of 747.s end their lifes as freighters.
guess its primarly a economic issue, that maintainace cost etc increase beyond the point were its economical to fly the plane.

A worst case scenario:
https://en.wikipedia.org/wiki/Aloha_Airlines_Flight_243

[Busher]

Probably not pressurized ones.  Pressurization limits an airframe's longevity whereas aircraft that are not pressurized can pretty much be flown forever so long as they are maintained.

That's what "D" checks are for. Basically an airframe renewal. They often go on until the cost of the renewal gets excessive.

[Ripsnort]

Pressurized planes have a limited lifespan due to fatigue in the fuselage due to the pressurized cabin expanding and stretching the fuselage when flying on high alts. A lot of 747.s end their lifes as freighters.
guess its primarly a economic issue, that maintainace cost etc increase beyond the point were its economical to fly the plane.

A worst case scenario:
https://en.wikipedia.org/wiki/Aloha_Airlines_Flight_243

That worse case scenario was unrelated to pressurization fatigue. It exposed the issue (below) but wasn't the culprit.

(NTSB) concluded that the accident was caused by metal fatigue exacerbated by crevice corrosion. The plane was 19 years old and operated in a coastal environment, with exposure to salt and humidity.

Ironically, they found this note on the floor of cabin after landing.