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Comment Re: So, pilot error? (Score 1) 353

In fact, even with two sensors how does the system know which one is the malfunctioning sensor?

It doesn't, but that's nothing unusual. There are many systems on modern aircraft which involve dual sensors. When one malfunctions, the aircraft throws up a maintenance message basically saying "there's something wrong with this system".

Here's the problem, though: if you have 2 sensors, one of which is malfunctioning, and they're giving different readings within the normal operating range, which one do you rely on and why?

The 737 MAX 8 is equipped with 2 angle-of-attack sensors. Currently only 1 of the 2 is referenced during any given flight by the MCAS (which switches with weight-on-wheels). Even if you now obtain and compare readings from both during a flight, which one do you rely on to trigger the MCAS?

If you go by the one with the higher AoA reading, you're in the same situation that you were in previously (i.e. that the aircrew were in on the fatal flight).

If you go by the one with the lower AoA reading, you risk missing a potential stall due to an undetected high angle condition.

The suggestion of a 3-sensor voting comparison at least gives you a fighting chance to determine which sensor is giving the correct reading.

Comment Distinct lack of communication (Score 1) 353

So, why didn't the aircrew from the previous day's flight pass that incredibly valuable information along to the next crew? Leave a note in the cockpit? Tape over the auto-trim disable switch in the Off position? Talk with someone responsible for staffing on the ground to pass along the details of the problem and the solution? I'm sure it was discussed with maintenance -- as evidenced by the work done on one of the angle-of-attack sensors overnight before the fatal flight -- but was anyone else made aware of the problem and solution? There seems to have been a distinct lack of forward communication ... and that's very troubling.

Comment Re:ludicrously and patently unconstitutional (Score 1) 503

Actually, it is. While it might be no match for jets and tanks, the average citizen has weaponry that is pretty much a match for any small arms. Whether or not they have the skills or numbers to effectively fight a SWAT team or other para-military force is another matter, but in general the weapons aren't a problem.

Except, you know, the tyrants generally DO have jets and tanks and the insurgents generally don't -- as in Syria. Bullets against armour, smart bombs, and chemical weapons ... the weapons ARE a problem. There's no comparison. Mosul presented exactly this scenario; Daesh (despite holding out for a remarkably long time) didn't fare too well, ultimately.

Comment Re:ludicrously and patently unconstitutional (Score 1) 503

Pro tip: whenever ANY tyrannical régime is enforced, it is done so with the aid of weapons/guns.

Pro tip #2: whenever freedom is defended against a tyrant, it is done so with weapons/guns (even democratically created laws are enforced by guns).

Yep, that's working real well in Syria.

Comment Re:As usual you have to determine cost/benefit (Score 1) 153

Melting 1kg ice takes 333.5kJ of energy.

However, you don't need to burn anything to melt ice.

Um, no. Clathrates are not (water) ice; they are crystalline structures of water and methane (or other hydrate formers -- typically hydrocarbons). They are not stable at typical conditions at the surface of the earth (which is why they typically form at depth under the ocean floor -- or in the wellbores of gas-producing wells). They decompose readily, releasing methane, when exposed to reduced pressure ... something any drilling engineer with northern/offshore experience can tell you.

To get clathrates to melt, you can reduce the pressure and/or hit them with a slug of methanol. Either measure would be something that any gas producer would be familiar with. It wouldn't be too hard to implement a production scheme along these lines and there has already been academic work published which considered a pilot scheme for Alaskan off-shore hydrate zones.

Comment Re:The recording industry needs to look at itself. (Score 2) 254

Great story!

And if you haven't yet read it, John Fogerty goes on along the same lines in his very readable autobiography, "Fortunate Son: My Life, My Music". Reading what Fantasy Records under Saul Zaentz did to that poor bastard made my blood boil ... so I went online and stuck it to Fantasy by ripping all the CCR streams I could find on YouTube.

Comment Re:I really hope (Score 1) 459

No, private industry with a profit motive will always be more efficient than government bureaucrats with no motive at all for efficiency and service.

Two words: Turing Pharmaceuticals

Yep, paragons of efficiency. Efficiently removing money from the pockets of the ill and the disadvantaged, that is.

Comment FORTRAN (Score 1) 633

on punched cards, put through a reader and then waiting for the operator to tear off your dot-matrix printed output to find out why it failed to compile (again). Within the hour, if they weren't too busy.

Later on a teletype connected via Gandalf modem to a Honeywell multics timesharing system.

Still later on a monochrome green CRT -- the first CRTs I'd ever seen. And the computer would respond in real time!

Finally from home on a Compaq luggable via 300 or 1200 baud modem over a telephone line. And then things really took off.

Comment Re:Fortran (Score 2) 633

Not from Calgary, by any chance, are you? They brought in Multics in my 3rd year of engineering -- after I'd already put in 2 years of late nights in the computing centre in the basement of Math Sciences, submitting FORTRAN programs in the form of punched card decks.

I can still read it, too; I read a paper last year with a FORTRAN subroutine printout appended and was able to pick out the transcription errors (undoubtedly made by the secretary who typed it up) which would have prevented it from compiling in the first place.

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