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Old 05-26-2008, 01:42 PM   #7
rdanner3
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Join Date: Apr 2008
Location: Central Alabama, US
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Quote:
Originally Posted by Greg View Post
How would you know, Raymond? I didn't hear anything about the touchdown velocity other than what was in the flight plan.
From the countdown of the descent rate during the last five reports (prior to the landing announcement being repeated excitedly several times) it sure sounded like it landed at several meters per second, which had to be a pretty hard "soft" landing. Of course, since you've seen the flight plan, you likely know more than I do. Unlike you, I'm not a rocket scientist, though I was a pretty avid hobbyist (flying-model) rocketeer when I was younger. (Still want to try flying my most ambitious project, since I think it'd go pretty high, perhaps requiring a NOTAM. Built the second and third stages, then lost both to a series of quick moves (6 in just over 2 years, and I'm not military) so still don't know if the thing could survive the intense thrust to weight ratios that were working up. (second and third stages, mated together, were absolutely stable in tests with lesser engines, as was the third stage on its own. First stage was causing me heartburn trying to build it with enough support for the four-engine mount, though. At 4 pounds of thrust each, F100 engines aren't easy to build mounts for out of what most hobbyists have available.))

May rebuild the design fully one of these days. Problem is, it will require assistance to track and recover, I expect, especially if I've properly calculated the apogee altitude (in excess of 11,000 feet) and there's significant upper-level winds the day of the launch! LOL (estimated thrust to weight of the first stage is a whopping 3.5:1. Third stage is close to 4:1. The thing is seriously overpowered, but the weights I'm basing those T:W ratios on might be off, too. Could be even more powerful, unless I reduce it to 6 engines (3 in first stage, 2 in the second, 1 in the third) from the original plan's eight. (4 in the first, 3 in the second, 1 in the third)
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