Message posted by wolfbane on December 05, 2001 at 9:41:35 PST:
Answer to SR-71/A-12 Quiz: Magoo had the best answers, and he was correct when he states that got about 92% right. However, at the speeds the SR-71/A-12 could travel, there was also a lift to drag ratio feature on the Blackbirds that none of the other Mach 3-class had. (As an aside, if the air was cold enough, the SR-71/A-12 could hit Mach 4). Ben Rich once openly stated that there were some things that were more than 30 years old, were breakthroughs and needed kept secret, and saying "....because other people don't have them yet." One of the problems that face the design team of Kelly Johnson and Ben Rich in creating the Blackbirds was how to drastically cut drag at Mach 3(+). Without going into a lengthy history of this "breakthrough," I'll only say this much. You all know of the grooves on top and bottom of the Blackbird's wings (the so-called wetted area). Well you also know that this feature was added to keep the wing skins from warping at high temps. And there gaps between each panel that would expand at high temps to Wolfbane
seal the integral wing fuel tanks. All this is correct. The corrogated longi grooves on the wing also gave a beneficial L/D ratio. The grooves cut drag more than 50% compared to a standard delta wing (or even the compression lift utilized on the XB-70). This type of drag reduction/lift production is known to most aeronautical engineers as the Magnus Effect. That is why sometimes the Blackbird could liesurely fly at altitudes that just was out of reach of the MiG-25.
In Reply to: SR-71/A-12 Blackbird Quiz posted by wolfbane on December 04, 2001 at 18:16:23 PST:
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