u/NewAd8721

I know the 767 originally wasn't designed with winglets, and many older aircraft—both passenger and cargo—have since been retrofitted with them. That's why I'm confused about some of the newest 767 freighters.

For example, UPS 767-300F N302UP (MSN 27240, line number 590) was delivered on October 12, 1995 without winglets. It was later retrofitted with blended winglets around 2014.

Meanwhile, UPS 767-300F N917UP (MSN 68363, line number 1375) was delivered brand new from Boeing on March 25, 2026, also without winglets.

Passenger 767s have been flying with retrofitted winglets for years, and cargo operators like UPS have also retrofitted many of their older aircraft. Considering these two UPS freighters were built 30 years apart, why are new-build 767 freighters still leaving the factory without winglets?

I'm also wondering whether Boeing even installs these winglets at the factory. Are the blended winglets actually fitted later by a third-party company or modification center after delivery rather than by Boeing during production? If so, why wouldn't UPS just have them installed before taking delivery if they provide a fuel efficiency benefit?

Are factory-installed winglets even an option on new 767s, or is there an operational or economic reason they're still added later instead?

I came across an Instagram post showing a 747-200 freighter fitted with enormous winglets for testing in the 2000s. I was wondering why this design was never implemented on later 747 variants.

From what I've read, the winglets were around 14 feet tall and were claimed to reduce fuel burn by about 7%. Considering how significant fuel costs are, I would think airlines operating large 747 fleets would have appreciated that kind of improvement.

I'm not an engineer, so I may be misunderstanding this, but if these winglets were installed on the 747-400 or even the 747-8, would they reduce fuel burn even further? Or were those aircraft already optimized enough that large winglets wouldn't provide much additional benefit?

Context below:

https://youtu.be/SUEBPEpimEI?si=WAnOdO\_kUoOZ40Ax

Credit to original owners:

(@dmvfireandpolice) Slide 1-2

(@northernvirginiapolicecars) Slide 3-6

Credits to orignal owner:

(@shelbycountysheriffsofficeal)

Credits to original owner:

(@dmvfireandpolice)

While watching Casino Royale I saw this weird aircraft that resembled a fuselage of a 747 and has B52 engines attached.

Did this ever existed or is this just CGI?

I saw a video about a person inquiring about transporting 100 tonnes of equipment from China to France, and they needed it all transported in one flight. A charter company was helping this person and advised her that the only aircraft that can handle 100 tonnes in a single transport flight is the Antonov An-124. I was dumbfounded by this because I thought these types of aircraft only operate under contracted agreements and scheduled cargo flights, and I also thought they were under fixed schedules, not charter operations. Correct me if I’m wrong, and also educate me on how the process works.

Here's the video that I was talking about:

https://www.instagram.com/reel/DXujqduCEEQ/?igsh=MXQ1dGF5cjQ3M2kyZA==