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Old 06-12-2008, 12:00 AM   #43
DGthe3
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Quote:
Originally Posted by wild_weasel View Post
Your math is good. Great explanation, but its not the time to circle that we are calling into question. It's the 6089.656 mile/hour (Mach 8) number. The SR-71 was fast, but not that fast. Let's say it can get pretty close to Mach 4...then its like 8 hours to circle the earth if we just double the time for half the speed according to the math where you already took into account altitude.
That assumes that the SR-71 doesn't need to refuel. It needs to refuel every 3000 miles or so. So it would need to refuel 8 times to go around the world. I don't know how quick that can happen, but it would add a couple hours to the time for sure.

Also, when I found the range from wiki I read this little tidbit: "The SR-71's Pratt & Whitney J58 engines never exceeded test bench values above Mach 3.6 in unclassified tests." They didn't exceed 3.6 in unclassified tests. Wonder what they got them up to in the classified ones . . .

Also, the stealthyness was compromised by its exhaust which had its own radar signature. Can't win 'em all.
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My sister's dentist's brother's cousin's housekeeper's dog-breeder's nephew sells coffee filters to the company that provides coffee to General Motors......
........and HE WOULD KNOW!!!!
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