Before NASA 1912-19581949 — The Doplex Flexikite
According to a file obtained by Stéphane Malbos from The Rogallo Foundation in 1997, Rogallo’s “second flexible wing prototype was made in late 1948 out of Doplex, which consisted of two sheets of cellophane glued to cotton mesh. Doplex was originally used for winterising windows and in greenhouses. The prototype was named and made as a gift for Rogallo’s daughter, Marie, when she was nine years old. Production versions of the kite were later sold later at F.A.O. Schwarz in New York under the name, Comet Flexi-Kite.” (bna-06)
We found no evidence of this Flexikite having been sold by F.A.O. Schwarz. The timeline is implausible. The first flexible kite patent (bi-cylindrical) was filed on November 23, 1948. There is no time to allow the new claim to be true. Marie Rogallo had just turned 8 years, not 9, in September 1948. The Doplex kite, although a poor example of a kite, was superior to the patented kite. Why would you patent an inferior design?
The earliest evidence that we have found of a Flexikite having been built is in 1951, when The Ford Times article was published. (doc-01)
When the original Flexible Kite patent was rejected, the rejection referred to Bach’s previous work.
Bach’s Flying Wing Kite patent was filed in May 1947 (pin-11), and is bi-conical. The patent refers to using “synthetic film” as a substitute for “limp light weight sheet material”. Rogallo was obviously influenced by it. Following this, he is only seen with bi-conical kites, even using a “synthetic film” (Mylar) for the sheet material.
Regardless of whether the Flexikite is an improvement on the never-seen bi-cylindrical patented design, it is certainly not Rogallo’s invention.
Aerodynamically, the Doplex Flexikite is a low aspect-ratio Bach Flying Wing kite. It is also similar to the Wanner kite design, a patent filed in January 1948, except Wanner has a fixed nose angle. (pin-12)
The Rogallos apparently tried to patent the Doplex kite because Patent Pending is written on the kite. It would be illegal to put a patent pending notice on an object unless the Patent Office had issued a Patent Pending notice for that object.
The US Patent Office does not routinely keep failed patent applications and there is no information about these patent pending notices in their digitized files. We do know that no patent was granted and it is obvious from our research that there was nothing novel about the Flexikite except for the material used for the sail. Bi-conical designs were covered by many earlier patents. See Chapter 4 (At Nasa 1958-1970 – Patents of Interest).
We found no evidence of this Flexikite having been sold by F.A.O. Schwarz. The timeline is implausible. The first flexible kite patent (bi-cylindrical) was filed on November 23, 1948. There is no time to allow the new claim to be true. Marie Rogallo had just turned 8 years, not 9, in September 1948. The Doplex kite, although a poor example of a kite, was superior to the patented kite. Why would you patent an inferior design?