Post #217,323
8/3/05 7:18:27 PM
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A few things
From: [link|http://www.disenchanted.com/dis/technology/fly-by-wire.html|http://www.disenchan.../fly-by-wire.html]
Adding a computer between the pilot and the plane was like sprinkling magic pixie dust: you got all of the benefits with hardly any drawbacks. Fly-By-Wire makes the aircraft lighter because it eliminates the bulk of the hydraulic systems. It makes it more maneuverable because the computer can perform hundreds more adjustments per second than a human. It makes passenger aircraft fly smoother, and with greater fuel economy. Plus on warplanes, wires were even less vulnerable to battle damage than regular control lines. Throw in enough redundancy and it even becomes less susceptible to failure than a traditional mechanical control system. Fly-by-wire's advantages were so obvious that designers were thinking about it in the 60s, and it was only computers they waited on to get small and powerful enough to fly a plane.
Both systems have their issues but lets face it, the modern airliner is beyond the point of complexity where a human or even a small crew can fly it reliably. Plus, hydraulics have their own problems as well. [link|http://www.answers.com/main/ntquery;jsessionid=38ig1fgo1wjos?method=4&dsid=2222&dekey=Japan+Airlines+Flight+123&gwp=8&curtab=2222_1&sbid=lc03b&linktext=Japan%20Airlines%20Flight%20123|http://www.answers.c...es%20Flight%20123] Tail strike severed all hydraulic lines leading to tail. An 802.11g local network with backup batteries/generators located throughout the plane might well have prevented this accident.
Japan Airlines flight 123 (JAL123, JL123), a Boeing 747-100SR-46, JA8119, crashed into the ridge of Mount Takamagahara in Gunma Prefecture, Japan (about 100 km from Tokyo), on August 12, 1985. The crash site, near Mount Osutaka, was named Osutakano-O'ne (Osutaka Ridge).
It was the worst single-aircraft disaster in history, with all 15 crew members dead, and 505 out of 509 passengers dead (including the famous singer Kyu Sakamoto) for a total of 520 deaths. There were four survivors, all passengers, though one of the survivors was an off-duty JAL stewardess.
...
The cause of the crash according to the offical report published by the Japanese Aircraft and Railway Accidents Investigation Commission, is as follows:
1. The aircraft was involved in a tailstrike incident at Itami airport on June 2, 1978, which damaged the aircraft's rear bulkhead.
2. The subsequent repair performed by Boeing was flawed. Boeing's procedures called for a doubler plate with two rows of rivets to cover up the damaged bulkhead, but the engineers fixing the aircraft used two doubler plates with only one row of rivets. This reduced the part's resistance to metal fatigue by 70%.
3. When the bulkhead gave way, it ruptured the lines of all four hydraulic systems. With the aircraft's control surfaces disabled, the aircraft was uncontrollable.
Or there is [link|http://www.airdisaster.com/eyewitness/ua232.shtml|http://www.airdisast...tness/ua232.shtml] Catastrophic rotor failure in tail engine severs all hydraulic lines to tail control surfaces. Same problem. Perhaps fly by wireless is really the way to go here.
"Whenever you find you are on the side of the majority, it is time to pause and reflect" --Mark Twain
"The significant problems we face cannot be solved at the same level of thinking we were at when we created them." --Albert Einstein
"This is still a dangerous world. It's a world of madmen and uncertainty and potential mental losses." --George W. Bush
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Post #217,325
8/3/05 7:34:07 PM
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Interesting.
Now so long as they don't put Windows on the internal network...
Regards,
-scott anderson
"Welcome to Rivendell, Mr. Anderson..."
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Post #217,328
8/3/05 7:56:51 PM
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Problem is digital failure is ... well, digital
A mechanical system can fail somewhat, and a human pilot can potentially work around the problem. If FBW shuts down, you've got almost no options. And if the current conditions are outside the design parameters, the system may react inappropriately. And even if the pilot does recognize the problem, the system won't let him correct it.
True, it's probably safer on average, but the feeling of insecurity is comparable to people who don't like flying. Flying is safer than driving, but if the plane fails you're fucked. FBW may be safer than FBM, but if the system fails ...
===
Purveyor of Doc Hope's [link|http://DocHope.com|fresh-baked dog biscuits and pet treats].
[link|http://DocHope.com|http://DocHope.com]
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Post #217,330
8/3/05 8:08:28 PM
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When it's accepted on automobiles, I'll be a believer.
Alex
The trouble with the world is that the stupid are cocksure and the intelligent are full of doubt. -- Bertrand Russell
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Post #217,334
8/3/05 8:47:10 PM
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United 232
That was a bad one. Passengers walked out of that cornfield and left the scene. UA had a hell of a time reconciling the manifest and trying to find everyone.
Did you know you have a better chance surviving a crash in a window seat? You're less likely to get knocked out or immobilized by items falling out of the overhead bins. That always sticks in my mind. That, and the fact that they can identify me by the serial numbers on the pins I have in my knee because, chances are, if I go down I'm either gonna be burnt to a crisp or fragmented into thousands of pieces.
What a fun job I have. :-/
Do regular people think about these things?
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Post #217,338
8/3/05 9:04:37 PM
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Probably not.
But I'm not regular either.
I tend to wonder what the sky would look like (briefly) as the wave of ionizing radiation from a supernova smacked into the other side of the earth, for all of about five seconds before I was blasted into oblivion, or if I'd even have time to think before being incinerated in nuclear hellfire, or how painful dying from ebola is...
I don't mind dying myself so much, I'm much more worried about awareness being wiped out. Note awareness != humanity in my book; I'm sure we will be superceded by our 'children' at some point. I hope they look kindly on their parents...
apt-get install godlike-powers
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Post #217,369
8/4/05 1:30:36 AM
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Re: Probably not.
But I'm not regular either. Eat more fibre, then.
Peter
[link|http://www.ubuntulinux.org|Ubuntu Linux]
[link|http://www.kuro5hin.org|There is no K5 Cabal]
[link|http://guildenstern.dyndns.org|Home]
Use P2P for legitimate purposes!
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Post #217,339
8/3/05 9:10:42 PM
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Re: Do regular people think about these things?
Occasionally.
On the trip to Nova Scotia this June, my wife and I camped near Peggy's Cove. Between the campground and the village is a memorial marker to the victims and responders of the downed [link|http://news.bbc.co.uk/onthisday/hi/dates/stories/september/3/newsid_2495000/2495403.stm|Swiss Air 111]. You may recall faulty wiring was to blame. Where one sat made no difference in this case.
While the memorial marker was not a destination per se, I took the opportunity to stop and see it.
Now that I'm retired and there is no business travel I'm always flying with my wife. While she's getting better, take-offs are a "white knuckle" time for her and I am generally holding her hand. One can't help but think of the "what ifs" at that time.
Alex
The trouble with the world is that the stupid are cocksure and the intelligent are full of doubt. -- Bertrand Russell
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Post #217,341
8/3/05 9:11:32 PM
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ICLRPD (new thread)
Created as new thread #217340 titled [link|/forums/render/content/show?contentid=217340|ICLRPD]
I have come to believe that idealism without discipline is a quick road to disaster, while discipline without idealism is pointless. -- Aaron Ward (my brother)
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Post #217,360
8/3/05 11:41:26 PM
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Regular?
Wouldn't know - I'm irregularly-irregular it seems. But I've arrived at a decent accommodation of all these transistors and their flaky-human directors. Hell, even the basic formula, F=MA from Physics 101-Remedial should give any car/cycle pilot some sobriety.. [Hah]
I read the links re crashes and have read others before. Since I've been around complex techno for ~1.5 careers, and particle accelerators (with their wiring, control systems, hydraulics, elaborate vac. systems etc.) are more complex than any of these special-purpose Jumbo Spam-in-Can contraptions:
I think it best to have settled your metaphysical questions, well before boarding. Not merely Probability/Statistics but all the human errors of inattention will be coming together quite beyond anyone's wishful 'algorithm for success'. You cannot "improve your personal chances" IMhO - that IS pixie dust.
We Know! that 'problems' are a function of n! in complex assemblages..
(n-factorial; for the non arithmetical: 6!= 6x5x4x3x2 = that kinda thing. BIG numbers fast)
Yet, I marvelled at seeing/keeping an entire accelerator complex running more than an entire week, 24/7 -- with just the ~10min checks inside, about every 4-6 hours; the 'running' continued All that time - only the particle beam was turned off, periodically. I'd have bet against this performance.. and lost.
(Mondo main accelerator magnet-ring plus a heavy-ion Linac 'injector' located up a hill - the two never were planned to be connected, hence a special beamline down that hill - had to work all this time, too.)
So I keep that which I Witnessed in mind, and don't worry about these planes.
(Though I will still despise their handling of Moi as crammed-in cargo, natch.)
Knowing it's a crap shoot is actually a relief! from imagining any need to personally 'Check things', y'know?
That's my own 'solution' to the jelloware's constant auto-imaginings,
Ashton
Now, for those who enjoy Worrying - think about all those nuclear missiles still. on. 24/7. Ready. Alert. despite .. the so evident Absence-of-Any SANE 'need' whatsoever.
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Post #217,404
8/4/05 8:19:13 AM
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I recently found out that my FIL worked out there.
He may have even been a predecessor of yours on a system. Physical Review Volume 75, Number 9, May 1, 1949, pp. 1456-1471
Proceedings of the American Physical Society
Minutes of the Meeting at the University of California, At Berkeley, California
February 3-5, 1949
[...]
H11. Radiation Field of the 184-Cyclotron.* W.K. Benson, Jr., R.L. Mather, B.J. Mover, and Joseph Yater, University of California, Berkeley - The distribution and intensity of the radiation field outside the shielding of the 184" cyclotron have been studied with various types of detectors. Three-dimensional surveys were made with proton recoil counter, calibrated slow neutron counter, and an ion chamber so constructed as to read approximately the "roentgen equivalent physical" dosage rate. Average values at normal areas of habitation are: 60 slow neutrons cm^-2 sec.^-1, 0.5 milli-rep/hr., and a fast neutron flux about an order of magnitude below tolerance. Determination of the actual value for fast neutron flux depends on energy distribution assumed. Studies of this are in progress. Calibrated indium foil measurements of slow neutron flux as a function of depth in the 10-ft. concrete shielding indicate, apart from transition and boundary effects, an attenuation with a half-value thickness of 7 to 8 inches, and a value at the outside surface in agreement with that mentioned above.
* This work was done under the auspices of the AEC. Joe enjoyed his time out there very much. He got his Masters at Cal. Did you work on the same system? (I'd imagine not - when I was at Chicago they had a lab building that was still called the Cyclotron even though it had been removed years before.) Joe's prose could be pretty flowery at times too. Hmmmmmm. The [link|http://aries.mos.org/sixdegrees/|Six Degrees] of Ashton B.? :-) Cheers, Scott.
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Post #217,480
8/4/05 1:52:05 PM
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{chortle}
Gawd.. Six Degrees ==> Someone here! has been around ShrubRove, somewhere somehow :(
{icky}
Cyclotron pretty long-tooth by my tenure; not useful for the project mentioned:
The Bevatron was a circle-with-straight-sections; 50' radius of the arcs, for perspective. Don't recall encountering the above folk, but Nobelists (and their groups, grad-students doing most of the work, natch) were as thick as Repos at a merger in the Caymans, chaired by ol' Chain-saw whatsisname.
The Super-Hilac produced many (most?) of the Trans-Uranic additions to the Periodic Chart (Thanks! Mendeleev) - many with Al Ghiorso's name on them. (Got a Roosian note from him at the time of Apollo-Soyuz linkup / with new Rooski stamp First-Day Cover! commemorating that event.)
Hooking the two together (ie using the heavy-ion capabilities of the HILAC as 'injector' for the 2.2 GeV/c Bevatron) became both thinkable and techno- practical in early '70s, despite their physical separation (including significant elevation! differences).
PDPs were arriving, to accommodate the pulsing of (beam optics) quadrupole fields, with requisite accuracy. Then too, the first synchrotron guide field ever to be minicomputer controlled - was the Bevatron, via PDP-8 (Thanks! Don Evans et al).
Put 'em together and create YAN acronym: the Bevalac.
(One MAD Party when the first beam made it all the way to full energy! - Glenn Seaborg + cast of hundreds vas dere: I too - in my mess-dress ex-AF uniform + Mad Hatter hat.) Got a great pic, too...
Fun stuff (and for moi, Trebly-so, for there being no marketing ergo lying, nor a 'product' to sell). I Love wissenschaffts; the antithesis of bizness fuckwittery.
As Sigourney said so eloquently, Lucky.. lucky.. lucky..
Physics Lives
homo-sap annihilates, at the drop-of-a-hat
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Post #217,486
8/4/05 2:03:52 PM
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Thanks. Is this your old haunting ground?
[link|http://maps.google.com/maps?q=lawrence+berkeley+laboratory,+berkeley+california&ll=37.876979,-122.250034&spn=0.003677,0.007135&t=h&num=10&start=0&hl=en|Google Maps]. The one with the brown roof (upper left) or the one with the, um, nipple, on the lower right?
I think Joe also did some work at SLAC, but I haven't been able to document that yet. I've little doubt that it was all before your time - he went East in the '50s.
Cheers,
Scott.
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Post #217,499
8/4/05 2:57:52 PM
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{snerfl}
WOW! - damn near down to the {ghost of my} Citro\ufffdn in the tiny parking lot.
Amazing the techno- which we now {yawn} not-even-Notice, what with instant satiation. Jaded, We (when not being insufferable, too).
Eerie ... those road names
and to know the bodies that go with them all.
('Course I'ze got a whole town: Ashton-under-Lyne IIRC ;-)
Yup, brown roof er Brown-roof :-0
Grand Vista of entire SF Bay Area, 3 bridges - from atop that roof!
(Where there were vents for stuff like Liq. Hydrogen targets n'such)
Would occasionally have the Shrammsberg and a goodie-basket from Narsai's *** up there. Once with SO. Lovely..
But it's dead, Jim.
Bevatron bought It (or rather - could no longer pay-for It) in '93.
No more Medical Cave for heavy-ion irradiation of tumored-folk: of the unique precision whereby [Bragg Peak] one could peel an orange, without harming either the inner pulp or the outer skin.
Priorities. You could build a new brewery or stadium for ..
Thanks for the mammary (Oh - that tit-thingie appears to be atop the 88" cyclotron)
Maybe - by now - a surveillance camera kiosk for Fatherland Security?
- 88" a much later, cleverer machine than the hoary First Big 'accelerator': the 184" Cyclotron. Not sure even, if that building still stands.
Ernest Orlando Lawrence pretty much started the rush
(with acolyte Livingston et al spreading physics-fever even to the Rust Belt) etc.
[There's yer one-line history of particle accelerators in the world]
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Post #217,516
8/4/05 3:23:32 PM
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ad some hair to this picture, slim down the jawline
[link|http://photos.olson-systems.com/displayimage.php?album=14&pos=0|http://photos.olson-...hp?album=14&pos=0]
gentleman in question actually assisted in building the first livermore computer,
thanx,
bill
Just call me Mr. Lynch \\
Any opinions expressed by me are mine alone, posted from my home computer, on my own time as a free american and do not reflect the opinions of any person or company that I have had professional relations with in the past 49 years. meep
questions, help? [link|mailto:pappas@catholic.org|email pappas at catholic.org]
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Post #217,393
8/4/05 7:39:24 AM
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not as much fun as picturing ground zero nuclear
what does one see before one vaporizes? On plane crashes sit in the middle window over the wings.
thanx,
bill
Just call me Mr. Lynch \\
Any opinions expressed by me are mine alone, posted from my home computer, on my own time as a free american and do not reflect the opinions of any person or company that I have had professional relations with in the past 49 years. meep
questions, help? [link|mailto:pappas@catholic.org|email pappas at catholic.org]
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