Oddly, back when the Estes D was released, I never had a failure with a D13...didn't fly a lot of them, no more than a half-dozen or so. On the other hand, one of the first D12's I flew suffered a massive blow-through at about 30 feet. Oddly, in a moment of offbeat humor, I had ended the 5-second countdown with "Detonate" instead of "Launch" (I know, BP in that size doesn't really detonate, but what did I know? I was 17).I do not think there has ever been a formal rocket motor recall. I think there have been some voluntary motor exchanges, but nobody wants to ship bad motors back to the manufacturer, or back up the retail supply chain. Probably the most notorious was the Estes D13, especially the November 1970 vintage.