A couple of days ago I reported that the Sagitta 900 plan and construction article was printed in RCM for April 1981 and is thus not Nostalgia class legal. As I reread the article, I discovered there is a wrinkle in the story.
The introduction, written by Lee Renaud, the designer, says in part: "The Sagitta is one of the new breed which has already proven itself a World Class design in both AMA and F3-B competition. First flown on July 20, 1979 (the tenth anniversary of the first flight of the original Olympic 99 and Neil Armstrong's lunar landing) -- Sagitta has been very successful. The version described in this article is the original "gas-bag" which I flew to 3rd place in the 1979 International LSF Tournament. This same ship was flown by Skip Miller after the contest and turned in sub-10 second speeds over the FAI F3-B course. Further developments of the design with straight wings and ailerons, plus fully sheeted wings helped Don Edberg to gain a place on the 1981 USA R/C Soaring Team. Dwight Holley also gained his team spot flying the version described herin, with a thicker stab section to suit Dwight's flying style. Four of the top six places in the Team Selection Finals were gained by Sagittas, including those flown by Skip Miller and Larry Jolly." So although the design was not available to the public before the April 1981 RCM issue hit the stands (or whenever the Airtronics kit appeared), it is clear that it was used in a sanctioned contest in 1979 and several people had built and were flying it in time for the 1981 Team Selection Finals (probably in 1980 given publication deadlines, etc). Well, when you make class rules, you have to draw a line somewhere. The Nostalgia class rules I have read would still not allow the Sagitta 900 because it wasn't "released" before 1/1/80 but it is clearly a near miss. A slightly different implementation of the rules might allow it. >From a technical point of view, the thing that sets Sagitta apart from predecessors is probably the Eppler 205 coupled with the relativly low aspect ratio (10.9 mean, 9.9 root). Remember that this occured at the time that speed was just becoming a significant event in U.S. thermal glider competition. Before that it was pretty much all duration and landing as far as contests were concerned. Sagitta was one of the first, perhaps the very first U.S. design that could go fast reasonably efficiently as well as thermal well and manouver well for landing. In that sense it probably makes sense to disallow it from Nostalgia. Up to that point speed was mostly not a big concern in thermal machines except for those doing cross country. Mark Holm [EMAIL PROTECTED] RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]