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THE WAY I SEE IT By NEVILLE WILLIAMS Jump start your new car and blow up the electronics! In October and November, according to a Victorian reader, I exaggerated the vulnerability of fly-hywire technology hut paid too little attention to the problems of electronic management systems in modern cars. They are especially at risk, he says, when jump-starting a car which has a flat battery. Most SILICON CHIP readers would relate more readily to everyday problems in the family car, particularly a new one, than to arguments a bout the control system of an aircraft in which they may never get to fly. But to make life easy, I present the letter as written and discuss the subjects in the same order. Here's what the reader has to say: Dear Neville, I feel a bit uneasy about the views expressed about the A-320 in the October and November issues of SILICON CHIP. Accordingly, I have copied for your perusal an article from "Electronic Engineering" for July 1988 relating to this aircraft and others to come. It shows the other side of the coin. After reading it, I hope you won't look too much at the gloomy side of new technology in aircraft design. While I agree that an aircraft can be shot down by a bolt of lightning, I believe that flying in a modern aircraft is still much safer than driving around in the new cars of today. They are lighter (they use thinner metal) and are less reliable electrically. I have heard stories recently of the 66 SILICON CHIP electronics being completely destroyed by jump-starting a modern car which has a flat battery. This, I would add, with the batteries connected the right way around. It surely indicates very poor design on the part of manufacturers, in not adequately protecting the electronics from the voltages and situations that one can encounter in a family car in the course of everyday use. A major electronics failure can be both expensive and time consuming, because it may completely disable the car. Maybe you could prepare an article on the do's and don'ts of a modern car and its electrics. I trust that you will find the enclosure helpful. You may not have had access to it prior to writing your article. W. K. (Ascot Vale, Vic). Thank you, W. K., for the article, which I had not previously seen. Despite the July 1988 dateline, it would almost certainly have been set up and printed well before the A-320 crash on June 26. For the author, Pierre Baud, President of the Flight Division of Airbus Industrie, it must have been an agonising experience for an article extolling the design of the A-320 to coincide with such a public crash during an exhibition flight; more than that, to hear worldwide speculation that the crash may well have been due to a catastrophic failure of the much publicised FBW (fly by wire) control system. Baud's article emphasises the care taken with its design and the high order of redundancy provided as a precaution against possible equipment failure - although it probably doesn't go beyond what one would expect, anyway, in such a new and commercially important aircraft. There is no way that I can do justice here to Baud's 4-page article but the following brief summary will give readers some idea of its content: • FBW control, in analog form, has been in use in the Concorde since 1969 and to a limited extent in digital form in earlier models of the Airbus since 1983/4. • With a response time of not more than 5ms in some functions, the computers can intervene to protect the aircraft against stalling, excessive speed, unduly violent manoeuvres and the effects of windshear - a phenomenon that has been a key factor in several major accidents in the past ten years. • The FBW system in the A-320 relies on five main computers, of which any one of four can fly the plane independently of the others, largely obviating the risk of hardware failure. • At the same time, the risk of coincident software failure is minimised by the deliberate use of dissimilar processors and dissimilar processor languages in paired computers. Meet the "Oscilloclast" By way of a complete change of subject, I would like to pick up again the theme in the last issue: pre-occupation with the supposedly therapeutic qualities of electricity. I had intended to leave it to readers to comment further but, as it turned out, I came across an article on yet another " revolutionary" discovery: an electrical procedure, also from the early 1920s that might well have given last month's Dr Rogers and his " Neurophonometer" cum "Kiro-Vox" a run tor the American " get well" dollar. Under the heading " The Electronic Reaction of Abrams ", it was the subject of a series of articles in Pearson 's Magazine (New York) which described it as " the most revolutionary discovery of the age - the Abrams method of diagnosis and treatment" . Dr Albert Abrams, it appears, had established a clinic in San Francisco "to which hundreds of physicians from all over the United States were sending specimens of the blood of patients so that the Abrams method of diagnosis could be applied to them ". The report continued: "each blood specimen is placed in turn in an electrical device invented by Dr Abrams and the vibratory rate is read oft by varying a rheostat the readings indicating whether a disease is present in the patient, • All computers are normally ac. tive at all times, some actually flying the aircraft, the others fully updated and on instant standby. Constant input/status self-checking alerts each FBW computer separately to any inconsistency and possible fault. • In the unlikely event of progressive computer system failure, a design philosophy of "graceful degradation" transfers control logically to the pilots. This initially involves the "wire" facility but, in an extreme emergency, transfers direct control of the mechanical tail and rudder trim. • The aircraft has been the sub- the nature of the disease, its locality and its history" . "When the disease has been determined , a course of treatment is prescribed using another invention of the doctor's - called the Oscil/oclast - which is said to be capable of breaking up ordinary alternating current into various vibrations" . The basic idea, apparently, was in some way to subject the patient to electrical impulses at the frequency of the disease (?) and thereby destroy it. I quote: "Ascertain the vibratory rate of the disease, ascertain what current will cancel that reaction, and then pour into the body a current at that rate , and you destroy the activity of the germs". In between those last two quotes were observations attributed to Upton Sinclair, "the great American novelist" (?) and a Dr W. G. Doern of Milwaukee, ne ith er of whom contribute anything meaningful to the text. Even Dr Abrams is a bit vague about his so-called "discovery of the age " . Again I quote : " Dr Abrams makes a guess as to why the same vibratory rate destroys the disease activity. He tells how once he saw Caruso at a dinner party tap a wine glass and determine the musical note at which it vibrated, and then sing the note at the glass and shatter it to fragments .. . Dr Abrams believes ject of exhaustive flight testing, such that it satisfies all international airworthiness authorities. The segregation and shielding of FBW cables has proved effective against" exposure to deliberate high RF fields from radars, etc and simulated lightning strikes. It's a reassuring article but the undeniable fact is that the aircraft did crash and burn in a very public manner at the Mulhouse Airport on the Franco-Swiss border. It was little short of a miracle that only three persons were killed out of the 140-odd passengers on board. It is also true that the crash occurred in circumstances that sug- that this is what happens to the disease germs ... that which was a disease germ becomes something else". By way of a further illustration , he quotes the transubstantiation of elements (uranium /radium/lead) and suggests: "that by means of a current, he can change the atoms of a cancer into the atoms of something else ". Skipping a few more paragraphs, I came upon a couple more quotable statements, one reassuring, the other interesting: " Asked if the applied vibrations might not injure living tissue, he answers that there is nothing in the normal body which yields the same vibratory rate as disease" and : "Dr Abrams has ascertained that pain has a certain vibratory rate , and if you have a pain , he can locate it; also, he found the vibratory rate which cancels pain and has taken the Oscilloclast to a dentist's room and demonstrated to several dentists that work, otherwise agonising , could be done practically without sensation". Strange, isn't it, that such a marvellous device should have disappeared without trace . Especially as $50 ,000 is said to have been pledged to promote its use in a childrens ' clinic by the good doctor "who happens by rare good fortune to have been a man of independent means ." gested either pilot error or an aberration in the computerised control system, rather than a mechanical failure in the aircraft itself. Moreover, allegations by the French Airline Pilots Union of an official cover-up and argument about the conduct of the inquiry seemed to point to the electronics. What's his real concern? Having read and re-read W. K.'s letter, I am still not clear as to the reason for his unease about the views expressed in the October issue. Was it because I did not specifically lay the blame on pilot error or did he construe the entire FEBRUARY1989 67 THE WAY I SEE IT - CTD article as an opportunistic and thinly veiled attack on the Airbus philosophy? In fact, the article on fly-by-wire and the electromagnetic environment was planned in early June and was nearing completion when the Airbus crashed. I simply added a couple of pars mentioning the crash and speculation about the cause, qualified by the remark "the matter may possibly have been clarified before you get to read this .. ." As it transpired, the official report blaming pilot error was published about a month after the crash but rather than start pulling finished pages around at that late stage, it was decided to let the qualification run as it was. The remainder of the article was simply an open-ended discussion of the conflict between critical electronic equipment and the electronic environment. I posed the question as to whether the problems really had been resolved as completely as some would imagine. It proceeds to the proposition that, for critical electromagnetically vulnerable links, our thinking should perhaps be towards the use of fibre-optic technology rather than metallic cables. The November article continued the theme, prompted by a fortuitous episode of Quantum on ABC TV. It explained the problems that NASA had experienced with lightning discharges and detailed their current research in that area. The statement about the frequency of lightning strikes on aircraft in American skies was Professor Krider's, not mine. What I personally described as the "odd-ball scenario" of technologists working towards disparate objectives is surely self-evident. No, I am not anti-technology or anti-aircraft. I, too, can relax aloft with a greater sense of content than when negotiating endless curves on a lohg car journey. I agree that lightning strikes rarely damage conventional aircraft but it would be nice to be assured that FBW planes would be no more vulnerable in the same situation. Electronics in cars As for electronics in motor cars, that's another story, in more ways than one. Says W. K.: "I have heard stories recently of the electronics being completely destroyed by jump starting a modern car that has a flat battery. This, I would add, with the batteries connected the right way around". I, too, have heard such stories but seeking confirmation or otherwise, I rang a friend connected with the NRMA (the National Road Motorists' Association in NSW). "Yes" , he said, "electronics can be destroyed in that situation" and, while he didn't profess to know all the answers, he was certainly familiar with the problem. First off, he suggested, don't take too much notice of claims that the jump leads were correctly connected. Reversing the polarity is probably the single most effective way of wrecking the electronics but someone who has just been guilty of doing that is often loath to admit it. The next most effective way, he said, is to jump start the engine with correct polarity, then immediately remove the jump leads and rev the motor madly to assure all and sundry that it really is running! A flat battery, he explained, cannot be relied upon to smooth the load spikes, especially if someone races the motor immediately after starting. Up go the spike voltages and "phut" goes one or more of the devices in the black box. He made the further point that excessive voltage is by no means a new problem. In other days, it has damaged indicator light globes and the odd clock or radio that has been left across the supply. But while annoying, such items are scarcely in the same class as an engine management computer. For how long, then, should one leave the jump leads connected? "For not less than five minutes", he said. "By that time, an otherwise good battery should be active enough to cope - especially if you're on the spot to double-check the voltage". He went on to say that, while a near worn-out battery was problem enough, they also had to be very careful with a good battery that had been flattened by leaving the lights on overnight or in an airport parking lot. "They get really flat", he said, "and sometimes take a fair while to reactivate". Open-circuit batteries I gather NRMA repairmen have to be particularly cautious about batteries which may have developed an internal open circuit. An open-circuit battery provides no protection at all against spikes and over-voltage from the alternator and exposes the system to damage immediately the jump lead is disconnected. If a battery shows little or no voltage at all across the terminals on a sensitive meter "it's a case of getting a replacement battery or a tow truck''! One aspect I omitted to check with him was the possible effect of a "crook" battery connection - the corroded clamp or the rusty chassis bolt that stalls the starter motor. It might also expose the system to spikes or over-voltage from the alternator but I would expect the "won't-start" problem to show up first. Reversing the polarity of jumper leads is probably the single most effective way of wrecking a car's electronics but the guilty are often loath to admit it 68 SILICON CHIP Electronic devices other than in-car computers can also be vulnerable & expensive. These include 2-way radio systems and in-car telephones How extensive or how expensive the damage may be to an electronic control system depends on the nature and the number of separate "computers" in the particular vehicle. The truth probably is that computer breakdowns are never cheap; it's just that some are more expensive than others. One parting point made by my informant was that, these days, electronic devices other than in-car computers can be vulnerable and expensive. As a precautionary measure, when dealing with battery problems, he recommends pulling the fuses supplying 2-way radio systems and in-car telephones. I'd be surprised if other SILICON CHIP read.e rs don't have a few corn- ments to add to the above. That brings me back to W.K.'s proposition: "It surely indicates very poor design, on the part of manufacturers, in not adequately protecting the electronics from the voltages and situations that one can expect and encounter in a family car in the course of everyday use". It surely does, which is exactly what we had in mind on page 39 of the October issue. Thankfully, some of the early problems are being sorted out but there are still a few to go. The pity of it is that the weaknesses had to be identified the hard way. My expressed hope was simply that it wouldn't be like that in the aircraft industry, where a great deal more is at stake. Harking back to that, it's ironic that the A-320 crash should have been due, not to any failure in the electronic control system, but to a couple of pilots who would appear to have taken more notice of the chips on their shoulders than those in the FBW equipment. I quote from a report, as published: "The crew contemptuously dismissed warnings emitted by the computers, the pilot saying several times: knock that one off, it's getting on my nerves". As I write, the first of the new A-320 "Skystars" has just landed in Sydney. One would sincerely hope that our own pilots will not be quite as nonchalant! It CONTACT INTERNATIONAL PO BOX 390 COW ANDILLA, SA 5033. 2/283 BURBRIDGE ROAD, BROOKLYN PARK, SA. MAIL ORDER MAIL ORDER COMPUTER PERIPHERALS 00027 MULTI 1/0 CARO + FOC . 00372 PRINTER CARO. 00390 TOWER COMPUTER CASE + OISPLA Y 00387 XT CASE + LOCK . 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