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Comment by nyx_ | Hacker News Reader

The slide in the article has the same text, but is a recreation of the original (The Calibri typeface used wasn't part of PowerPoint until 2007).

The original slide can be seen in the full report linked in the article:

https://www.edwardtufte.com/bboard/q-and-a-fetch-msg?msg_id=...

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Why would someone recreate that slide instead of just using the original? Gah, that's sloppy reporting. Makes me suspect the entire story told, now that you pointed that out.

There's other sloppiness here as well, like treating the orbiter velocity as the determining factor (nine times the speed of a bullet...) when the delta-V between the foam and the orbiter is the more pertinent information.

The author comes across like they have an axe to grind (maybe rightly so) but should make better efforts at getting technical details right in an article about the perils of miscommunicating technical details

Thanks for pointing this out. I noticed the typo of "hanrd" ("hard") on the re-creation and drew the further conclusion that they weren't even taking the issue seriously enough to pay attention to their slide content. Even though it doesn't change what ultimately happened, it's nice to know that someone was paying at least cursory attention.

Indeed. I missed "hanrd" on my first read through, but "Vaires" and the stray "?" jumped out at me. The original slide is much more readable, and "Flight condition is significantly outside of test database" stands out as almost the conclusion rather than being buried in noise. Talk about a strawman. (Still a bad slide, though.)

So if I'm reading this right, the previous testing was done with a 3 cubic inch foam block at 200 ft/sec impact velocity... and the foam ramp was 1900 cubic inches and going 900 feet/sec at impact.

This is like saying "shooting someone in the head with a BB gun doesn't kill them, so we think shooting them in the head with a shotgun slug should be fine."

What on earth were these people thinking?

That same linked page by Edward Tufte (of data visualization fame) has a proposed revised slide that would have more adequately conveyed the risk

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