As some of you know, I have a pretty low opinion of most journalists, especially those who try to cover a topic which has even a tiny amount of technical content. I’ve met and worked alongside many of these journalists over the years, and I don’t know which group is worse: the ones who don’t know anything technical but figure they can skate by; or the ones who know just enough to be dangerous and wrong, and that they can handle the topic.
This week’s example is the coverage and hysteria about the MD-80 jet aircraft, mostly operated by American Airlines, and the emergency stand-down of these planes for inspection (and thousands of cancelled flights) due to a possible wiring problem. This was described by most of the media as "faulty wiring", "dangerous wiring", "miswired", and other very skewed, misleading terms. They made it sound as if the AC-supply lines were plugged into DC supplies, or that connectors and cables were mismatched or even crossed.
Only the Wall Street Journal, among the major media, actually had some specifics: "it [the FAA] determined that American Airlines’ repairs didn’t meet its painstaking standards, which dictate details such as which way retention clips holding the wires face, toward the back or front of the aircraft. This matters because the clips could chafe the coating on the wires, causing wear that would expose the wiring to leaks from fuel or hydraulic fluid. . . . some wiring was secured at intervals exceeding the one inch dictated by regulations." (I did find some pictures, after a little on-line searching, and the cable bundles were laced down pretty tightly, with lots of clips and ties closely spaced. But the caption didn’t say if the picture was of "good" or "bad" cabling!)
Now, I know that proper cable dress is very important to long-term reliability (I have been tripped up by cable sloppiness and poor strain relief too often) but does this aircraft-wiring problem constitute "dangerous wiring" or even "miswired"? I’ll let you be the judge!
On a more mundane topic, here’s a thought problem I came across: my laptop PC was doing some disk-intensive work, and fairly warm air was coming out the exhaust. So I thought I would raise it a little, off the flat surface of the desk, to allow airflow and better cooling.
But then I thought about it some more. Air, especially stagnant air, is a poor conductor of heat. Maybe it is better to have the bottom of the laptop directly on the desk, which could act as a heat sink? How good is the thermal contact between the laptop and the desk, and the heat-sinking properties of the wood top? Pretty soon, I was convinced that the intuitive ideas to lift the laptop might actually be counterproductive.
I know that you can buy thermal mats to go under a laptop, to improve surface heat-sinking, but I am not ready to do that. Before I do anything, I want to know if placing the laptop flat on the wooden desktop is better or worse, from a thermal perspective, than raising it a little. And what about a metal desktop, or a plastic laminate desktop? I’d be interested in hearing your views, especially if you can model the thermal situation (and hey, it would make a good article, too!).
OK, enough off-the-subject thoughts. Check out the solid array of diverse technical articles below. And while this week’s ebb-and-flow has fewer new products than last week (don’t read anything into this, it’s a normal weekly variation we see here), we have more news and short items than last week.
Until next week. . . .
Bill Schweber, Planet Analog Site Editor
(formerly @cmp.com; same "desk", new company name)