Raked wingtips are not new... What can be legitimately patented?

Question

In reference to the patent: US6089502 , Boeing's patent on the Raked Wingtip

I'm struggling to understand how this patent is legal. When I went through the process of getting my patent, I was taught that only a device can be patented, and that it is not legal to patent an existing device to use on some "new" thing. In other words, I cannot patent the use of pneumatic tires on cars that are manufactured after 2020. While I could claim that this is completely new and novel, in that, so far no one has ever put a pneumatic tire on a car manufactured after 2020 (as it is presently only 2017), the device of a pneumatic tire has already been invented. I cannot patent this "new" use of the existing device.

Patent #US6089502 is a Boeing patent on the raked wingtip device. The earliest example of the raked wingtip I know of was used on the Rumpler Taube aircraft as far back as 1910 (an example of which hangs in the Boeing Museum of Flight). In the past 100 years, there have been many other implementations of raked wingtips used on aircraft. I don't understand how Boeing can patent the invention of putting a raked wingtip on a new airplane that flies at transonic speeds. It's the same invention used on the Taube, but used on a "new" airplane that flies faster. To my understanding, this is not a patentable invention. Am I missing something here?

How did Boeing get this patent granted, and how is this patent legal, or enforceable?

Answer 1

Almost anything that has been invented can be improved upon. In this case, Boeing is patenting a very specific design of raked wingtip which the the patent examiner found sufficiently novel to merit a patent. The examiner cited 9 previous patents in addition to two non-patent documents. Since this patent was issued it has subsequently been cited by 63 patents and applications which attempt to patent other improvements. As for your referencing the Taube, I would argue that despite the "bird-like" wing shape, it is unlikely to cancel out wingtip vortices which is the point of the Boeing patent. Also, it in no way teaches the technology demonstrated in this patent which applies to aircraft flying at or above Mach 0.7. However, Wikipedia has a nice article on wingtip devices which notes a patent from 1897 which is before the Wright Brothers first flew.

One note on patents that contain improvements on existing technologies. While the improvement may be protected, it doesn't guarantee freedom to operate from earlier patents. Thus, even if you improve upon an earlier device, you might need a license to use or sell your improvement.