Friday, May 22, 2009

Lenticular rockets: FGG-3/Darque Sol/Pye Wacket

I just ran across this stuff and will present it in the order I discovered it vs. in any logical sequence.

First, I saw a brief report about a project called FGG-3/Darque Sol on the Tripoli Pittsburgh site. The FGG-3, named after Tripoli founder Francis Glenn Graham, is a lenticular rocket. That is, it is saucer shaped. The brief report indicates the project was mostly successful. What makes this saucer rocket unique is that it flew with the saucer edgewise rather than in the typical sport rocketry saucer configuration. (Aside: Francis is also a physics professor and an expert on, well, unconventional rocket designs. He authored the booklet Monocopters, which is available from Apogee. He also frequents the Monocopters Yahoo Group. Monocopters are some of the more 'normal' things he has tried.)

A quick search led me to this page on the Darque Sol project. This has plenty of info on the build and the testing leading up to the flight on April 18th, 2009. However, the flight report is not completed. In short, it is a 36" x 6" fiberglass shell molded from a foam core. The motor mount is on its edge and it recovers with rear ejection from 2 tubes mounted in parallel to the motor mount. The motor for the test flight was an hefty 'EX' L640.

The site also provides background research on the Convair Pye Wacket, which the FGG-3 was patterned after. The Pye Wacket was a conceptual Mach 6.5 missile intended to defend the North American XB-70 Valkyrie Mach 3 bomber circa the late 1950's. This section of the site, and the provided links, are also very cool. I grabbed the following photo from