Tom Rivellini: The October tests... Yeah. Well, the October tests were the first drop tests done on a Mars Exploration Rovers bag, fresh bag, just fabricated, with all of its associated changes, with a Mars Exploration Rovers lander which is considerably different from the Mars Pathfinder lander - it's physically larger, it's physically a lot heavier, it has different interfaces. And the drop conditions were different. The velocity was slightly lower but the lander mass was a lot heavier, so they made up for each other. And the rock field was different. We tried a different rock field than we did on Pathfinder. We thought we would get a little bit smarter. And a little bit more conservative. So we made the rock field a little bit more aggressive. And you know we got some failures we just did not expect. We blew out some end caps. We got some tears in some areas between the tendons, and you know we were really scratching our head trying to figure out why that happened, and, truth of the matter, we don't really know. Our best conjecture is that we just hit areas that were not exercised during Pathfinder. We did not hit those areas when we were doing our drop tests. So that implies that we either got lucky on Mars, we got lucky in our drop tests, or we just did not look at our books well enough, and we did in fact hit those areas during Pathfinder and something else is going on. And then the end caps, you know, we're getting some rock strikes in some areas that, you know, on Pathfinder were working fine. Again, we don't really know what's going on. It could be just the subtle changes in increasing the numbers of layers of fabric, like I mentioned before... It's just a very difficult design space to work, because you make one little change over here, and it has effects that you would never imagine.
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