If there was ever a patent on raked wingtips, it must have surely run out by now. 747-400 1989 is 29 years ago.
First flight of the 764ER was in October 1999, so a standard 20 year patent won't last beyond next year. Unless Boeing didn't patent it till after first flight then it's null and void...
You can not patent something that has been out there for somebody to see. So if not patented before the first flight, than no patent. You have to patent it before you show the first picture of the bird to someone outside the company.
I was of course wrong with the 747-400, no raked wingtips on that one.
One could argue that the 747 had raked wingtips, just at an angle. However, the actual raked wingtips are flat. And come to a point. I believe the point is significant.
Boeing had to prove that the flat, triangular raked wingtips were superior to the art. There also is an issue with the sharp bend on 747 / A330 / etc. winglets, but Aviation Partners covered that in 1993. Boeing's raked wingtip being flat avoided that, and avoided paying Aviation Partners.
Boeing said that a 767 with blended wingtips was better than raked wingtips out to about 4 hours, after which raked wingtips won. Hence the 764, which needed all the help it could get, got raked wingtips. The 763 never did, despite the fact that it flies farther.
Airbus, by coming up with a continuously curved (not flat, avoids Boeing patents) (not a specific curved section, avoids Aviation Partners patents) continuously increasing sweep scythe-like wingtip, avoided all the other patents. And probably got a percent or so for equivalent sized wingtips.
With regards to the A320 sharklet, it is a direct copy of the Aviation Partners blended winglet. Airbus tried various things from 2006 to work with, and against, Aviation Partners. After over a decade, the matter was settled in Aviation Partners favor
Airbus has resolved its winglet dispute by making a large payment to Aviation Partners, according to sources who were familiar with the matter but asked not to be named to protect business relationships.https://www.bizjournals.com/seattle/new ... spute.html
Airbus worked with Aviation Partners from 2006 through 2011, in an effort to modernize its A320 family of jets. In 2011, however, Airbus announced that it came up with its own design, which it branded "sharklets," and obtained a patent in Europe. In December 2011, Airbus filed suit in Texas seeking to invalidate Aviation Partners' 1994 winglet patent.https://en.wikipedia.org/wiki/Aviation_Partners_Inc
Some more about the joint venture, Airbus patent, and lawsuitshttps://www.flightglobal.com/news/artic ... et-367720/
There was a short, but spirited discussion on a.net 5 years agoviewtopic.php?t=553441
The majority opinion was that it was all about the details. However, it is quite possible to patent a feature (if nobody else did it first), which is why Aviation Partners won.