There was a delay getting the December rewards out, and a further delay in putting this notification together that the rewards are available… so it might be only a short-ish time before these are gone, replaced by the *January* rewards. So if these look of interest… act fast!
PDF Document: “Design Study for an Air Force Model F-82E Airplane Modified to a Ground Attack Aircraft with Allison XT-38 Turbo Prop Engine,” a North American Aviation report from 1948. This was not for a simple engine swap-out… the cockpits were moved forward and the engines located behind them, driving the props with long shafts.
PDF Document: “SAM-D Air Defense Weapon System,” a 1973 US Army description document of what would become the Patriot missile system.
Large Format Diagram: a large-format full-color (w/bonus grayscale versions) diagram of the X-20 Dyna Soar. Very detailed and clear. Looks great on a wall (believe me on that!)
CAD Diagram: Boeing Model 853-21 “Quiet Bird” a 1961 design study for a low radar cross section (i.e. stealthy) research aircraft.
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