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Death by PowerPoint: The slide that killed seven people

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Re: Death by PowerPoint: The slide that killed seven people

#121

Post by brazzy »

utborin wrote: post #103
VeninVidiaVicii wrote: post #94

Earlier quoted context omitted.

For the past two years I have worked in the local emergency room as a technician working on getting some clinical experience. Let me tell you, in the constant face of life and death, you really just develop a kind of "danger fatigue" and even the most critical moments become somewhat prosaic. You begin to develop a false sense of security after nobody really does from a gunshot wound. Then, someone septic comes in, a…

A very similar phenomenon happens in aviation—we call it complacency. Thousands of successful takeoffs in a row make it hard sometimes to remember that each one is a completely independent event. The way I fight it is by explicitly reminding myself that just because something worked yesterday, that doesn't mean I can skip a step today or let my guard down at any point. It really does take deliberate thought though. F…

Same thing for rock climbing, and complacency born from routine is exactly the problem: you tie knots that your life will depend on every day, thousands of times, and then stuff like this happens to some of the most skilled and experienced people:

- get distracted while tying the rope to your harness and leave the knot unfinished, fall 20 meters from the top of the climb (Lynn Hill, by sheer luck only broke her foot and elbow)

- use a slightly unusual rope setup and when preparing to be lowered, tie in on the wrong side of the anchor, fall 14 meters onto rock (Rannveig Aamodt, broke her spine, pelvis and ankles)

- have your partner point out damage on your harness, shrug it off because there's plenty of safety margin, continue climbing for 3 days in a manner that puts repetitive abrasion on exactly that part of the harness, have it snap while rapelling and fall 150 meters to your death (Tood Skinner)

Re: Death by PowerPoint: The slide that killed seven people

#122

Post by stormking »

TeMPOraL wrote: post #106
Izkata wrote: post #62

Earlier quoted context omitted.

> wtf does "overpredicted" mean? That's the second largest font, and it has no visible meaning? Honestly, it reads to me as being along the lines of "overestimated" - and in this sentence would mean "reality wasn't as bad as our predictions, so we have a lot more leeway than we thought".

A mathematical model (here, the crater equations) predicts something. If the prediction turned to be larger than reality, you could say that the model overpredicted.

What you should say is that the model is wrong.

Re: Death by PowerPoint: The slide that killed seven people

#123

Post by caconym_ »

peteradio wrote: post #75
caconym_ wrote: post #69

Earlier quoted context omitted.

Yes, and my experience doing so only cements the opinion(s) expressed in my previous comment—to which I'm inclined to say your reply is not terribly relevant. Ambiguous, poorly presented, and technically dense are three different things, though they can all be present in the same place. Only two of them are necessarily bad.

So what exactly is technically dense/ambiguous in this summary presentation (remember this isn't the only information provided). Perhaps you'd like to review the full deck of slides rather than the single one picked by the asshole author, I'm particularly interested in the one titled "Damage Results From “Crater” Equations Show Significant Tile Damage" . https://www.nasa.gov/pdf/2203main_COL_debris_boeing_030123.p...

The title, "Review of Test Data Indicates Conservatism for Tile Penetration" is completely ambiguous to the point of being nonsensical. It is impossible to know in which direction the author of the slides thinks we should be conservative.

Ironically the slide you point out ("Damage Results From 'Crater' Equations Show Significant Tile Damage") seems to skew our interpretation of the next slide's title and content in the wrong direction. The former slide states that "'Crater' indicates that multiple tiles would be taken down to densified layer". That sounds bad. However, it also tells us that the "program" (assuming this means the Crater model) that generated this alarming prediction was "designed to be conservative". This would seem to downplay any concern generated by this result. Furthermore we are told that "Crater reports damage for test conditions that show no damage", further casting into doubt the predictions of the model.

And then, on the next slide: "Review of Test Data Indicates Conservatism for Tile Penetration". On the previous slide the word "conservatism" was used to tell us that the results from the "Crater" model may be on the high side, i.e. showing a problem where there is none, and that the test data show a much smaller degree of damage. This slide is about test data ("Review of Test Data"). On both slides we are told that compared to test data, the Crater results are inflated: "Crater reports damage for test conditions that show no damage", and "Crater overpredicted penetration [...] significantly".

Where does this leave us? The context of this additional slide makes the presentation even more misleading than the "asshole author", to use your delightful term, thinks it is. The title is not merely ambiguous; we are explicitly nudged toward the wrong interpretation of it. I have to thank you for bringing this additional context to my attention.

The author may in fact be an asshole (though I think your language is inappropriate in context), and his analysis may lack depth (I think it does to some degree), but in the simple matter of this slide being egregiously awful he's totally right. I don't know why you'd choose this hill to die on.

Re: Death by PowerPoint: The slide that killed seven people

#124

Post by TeMPOraL »

stormking wrote: post #122
TeMPOraL wrote: post #106

Earlier quoted context omitted.

A mathematical model (here, the crater equations) predicts something. If the prediction turned to be larger than reality, you could say that the model overpredicted.

What you should say is that the model is wrong.

That too. "Overpredicted" is a particular way in which this model turned out to be wrong for the problem it was applied to.

Re: Death by PowerPoint: The slide that killed seven people

#125

Post by ineedasername »

nyx_ wrote: post #2

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=...

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

Re: Death by PowerPoint: The slide that killed seven people

#126

Post by hughes »

speedplane wrote: post #98
hughes wrote: post #49

The speed listed in the introduction is wildly wrong. The foam could not possibly have hit at 28968 km/h - that is the approximate orbital speed of the shuttle. At 82 seconds into flight, the speed is about 700m/s (2500 km/h). Even using that figure would assume that the foam came to a dead stop instantaneously after detaching from the tank. I wouldn't be surprised if the relative speed was only 1/10th of that, putti…

> The speed listed in the introduction is wildly wrong. The foam could not possibly have hit at 28968 km/h The article said "[a]s the crew rose at 28,968 kilometres per hour the piece of foam collided with one of the tiles". It did not say that it collided with the tiles at 28k km/hr, just that it collided with it during it's acceleration to that speed. So technically it's correct, but I definitely agree that it it's…

In the next sentence the author also says the damage was caused by foam "hitting the wing nine times faster than a fired bullet." A bullet goes about 900m/s, and the "nine times" figure often symbolizes orbital velocity. It's clear that the reference is to the speed of the collision.

Re: Death by PowerPoint: The slide that killed seven people

#127

Post by runciblespoon »

I seem to remember it differently, what killed seven people was senior management choosing to ignore warnings about ice debris strikes on the wing during launches. On this one, they know ice had struck the wing, they choose not to have ground placed telescopes survey the shuttle, choose to not have the crew do an EVA and choose not have have a rescue shuttle sent up. The title has a nice ring to it all the same.

Re: Death by PowerPoint: The slide that killed seven people

#128

Post by pjtr »

speedplane wrote: post #97
pjtr wrote: post #93

"there is a huge amount of text, more than 100 words" "PowerPoint briefing slides instead of technical papers" Would technical papers have fewer than 100 words? If people can't be bothered to read 13 slides, what would they do with a technical paper? If people can't be bothered to make their message clear in slides, how would they create a readable technical paper? I don't like presentations that consist of "monotono…

> If people can't be bothered to make their message clear in slides, how would they create a readable technical paper? Slides are not the same as or replacements for technical papers. Even by comparing them, you're making the same mistake as these engineers did. Compared to a paper, the downsides of a presentation are that they are typically constrained to just 30-60 minutes, in front of a group of people who may be…

> you're making the same mistake

I assume you mean the "generic you", as it was the article quoting the NASA report that suggested the comparison.

Re: Death by PowerPoint: The slide that killed seven people

#129

Post by bumby »

peteradio wrote: post #79
bumby wrote: post #77

Earlier quoted context omitted.

Use of jargon is a huge impediment to communication in organizations like NASA and DoD. There's even a glib saying that you won't get your project funded unless you give it a cutesy/cool acronym. This ends up stifling communication because each group has its own pet vernacular that obfuscates meaning unless you are inside the circle. They could benefit from clear, concise communication that gets to the point

Read the full deck and tell me what is hard to understand: https://www.nasa.gov/pdf/2203main_COL_debris_boeing_030123.p...

I have mixed opinions. I agree that they conclusion is much more clear than the single slide implies. However, the slides do a poor job communicating in many other respects. For example, on the first non-title slide four separate acronyms are used, an only one is defined. (Incidentally, it's one that also has another, different, acronym within industry - M/OD => MMOD). Maybe everyone in the audience already familiar with these terms, but maybe they're not. I think in this case clarity should trump brevity. I think the original site has a particular, biased point of view but also that NASA can often do a poor job communicating.

The part I'm grappling with is how they came to that conclusion despite the "flight condition is significantly outside the test database" acknowledgement as alluded to in the original post. To me, this sounds very much like Challenger in terms of drawing conclusions without hard data to back it up. Easy arm-chair quarterbacking in hindsight, I know, but it seems the through-lines are psychological in nature, not engineering or technical problems.

Re: Death by PowerPoint: The slide that killed seven people

#130

Post by sailingparrot »

rossdavidh wrote: post #55
sailingparrot wrote: post #36

Earlier quoted context omitted.

How would a plain txt file have helped? As the person writing the txt/ppt/whatever it's your job to put the emphasis on the important part: the 600x difference. In text this means puting that at the beginning, in the title and in bold. The same is true in PPT, you have to outline the important stuff. It has to be visible at a glance. File formats don't solve lack of communication and listening skills.

Certainly not. The fact that plain txt would have been better than this, was meant to convey how poorly the format worked for the intended purpose (highlighting the most important information). I wasn't saying a plain txt file was a solution; I was saying that even plain txt, a very low-power format, would have been better than this, and since the ONLY PURPOSE of a PPT is to help you format things, this was a failure…

But it wouldn't have been better.... At best it would have been equally bad.
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