Engineering mistakes
Engineering mistakes
(OP)
Hello everybody:
Sometimes, something is wrong.
Just read this http:/ /www.wired .com/wired /archive/1 4.06/start .html?pg=9
Sometimes, something is wrong.
Just read this http:/
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RE: Engineering mistakes
I think I seem to recall Ohio, but may be mistaken.
"Do not worry about your problems with mathematics, I assure you mine are far greater."
Albert Einstein
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RE: Engineering mistakes
RE: Engineering mistakes
Most of the time, when going forward, it seems perfectly legitamate.
A modern day jetliner is an explosive device - the Twin Towers were brought down by jet fule burning.
"Do not worry about your problems with mathematics, I assure you mine are far greater."
Albert Einstein
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RE: Engineering mistakes
Hg
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RE: Engineering mistakes
Good luck,
Latexman
RE: Engineering mistakes
I work on aircraft, specifically structure, wings, critical stuff. But one day the boss came to me about a pretty bad mistake I made. He scolded me up and down, blah blah. I then told him, "the checker is more ...." He had checked my report. Quite amusing I think.
Anyway, my first 3 years of college were to become a aircraft mechanic. I continued my education to become an engineer (with the thought that I can always turn wrenches if I wanted to). My point is that I had my most valuable course ever during my mechanicaning class. The class was recip engine troubleshooting. This was after most all of our mechcanic type classes. Thus, we all though we knew everything. The teacher showed us how to run up engines (on engine test stands). Showed us the most typical problems (vacuum leak, timing off, etc). Then one day told us he had placed problems in the engines and we were to trouble shoot and fix. Then he said that we are all way too complacent and that complaceny KILLS. "you don't realize this but it's true." Well, we all pretty much thought he was full of @!#. We all walked out to our engines thinking no problem. Well no team fixed the engines (after several hours of desparately trying to solve the issue). Walked away with our tails between our legs and the most important lesson learned ever! I believe that one teacher has saved many many lives. Remember that complaceny kills. Also, engineers severly underpaid! (taken for granted if you will).
RE: Engineering mistakes
My best tech ever was an old aircraft mechanic, and he expained the aircraft mechanic anti- complacency incentive program; random rides in the airplane you've just fixed.
Mike Halloran
Pembroke Pines, FL, USA
RE: Engineering mistakes
RE: Engineering mistakes
RE: Engineering mistakes
RE: Engineering mistakes
The airship captain usually has the option of flying away from the storm; fabric covered buildings don't.
Mike Halloran
Pembroke Pines, FL, USA
RE: Engineering mistakes
If I remeber correctly ( it's been a while since I read it) the ghost of the crew of R-101 somehow got the story of why it crashed to the builders and flaws in sister ships were corrected. If the ghosts hadn't interviend we might never had the novel and movie "On The Beach" as Nevil Shute was a crewman on one of the British lighter than air ships.
http:
RE: Engineering mistakes
RE: Engineering mistakes
The first is that the structure was underdesigned. There was ZERO margin, based on the original design.
This was compounded by the fact that the contractor changed the fabrication drawings and the engineer(s) signed off without correcting the drawings, which caused a multiplication of the load at a joint that was undersized to begin with.
That's why the engineers lost their licenses for gross negligence, both in the poor initial design and negligent checking of the drawings.
TTFN
RE: Engineering mistakes
I don’t believe the reference to the DC-10s problems in Wired’s original article was presented accurately.
There was a book, Destination disaster: From the Tri-Motor to the DC-10, the risk of flying (Paperback) that discusses the issues with the DC10. My memory tells me it was a race to market between the L1011 and the DC10. I believe the book also alleges failures on the part of the FAA because they didn’t issue an Airworthiness Directive based on verbal assurances from Douglass that the cargo door problems would be corrected.
Kwan, I relate to the engine troubleshooting exercise because I remember doing that in A&P school after I got out of the service. The crew in my engine overhaul class was me and two other ex-marines. I know we found every fault but one (the one that fixed itself). The instructor jammed a wad of paper in one of the ignition leads and it burned through on it’s own.
See this old snapshot if you like. East Coast AeroTech (1978) ->
http://kontikilink.home.mindspring.com/ECAT.jpg
davidbeach, I like your story too. When I was in the Marine Corps, I was one of those parachute riggers. I mostly worked on A6 and A4 gear, 1973-1977. At the squadron level, we didn’t pack them. We did do a lot of 7 day inspections.
I must have done a thousand of them between our 12 airplanes. I was very conscientious about them too. I hand pumped the canopies open, looked at the 12 or so inspection points, and pumped it closed. When I climbed down, if I determined I didn’t remember what I had looked at, I’d pump it open and do it again.
In my 4 yrs of active duty, I found two parachutes that were packed incorrectly. Of course, I had them pulled and repacked. These were fairly sophisticated chutes for those times. Not the ordinary “rag in a bag.” They were zero zero capability chutes designed to save the crew at zero airspeed and zero altitude. I think it was fairly innovative for those days.
Sorry to indulge so many old memories. I was in awe a lot more back then.
RE: Engineering mistakes
The high profile matters may have judicial or senate enquiries and be in open forum. Day to day failures that are settled by insurance companies are hidden. How many of my contracts have confidentialty clauses that prevent me going public? 100%!!
Well I am at the end of my career and dont care. If I see bad things I bring them to the fore, not necessarily publcally but I let people in industry know. As engineers we need to speak out and get the truth out there. There are plenty of ways. Internet blogs are probably the fastest and most anonymous.
Geoffrey D Stone FIMechE C.Eng;FIEust CP Eng
www.waterhammer.bigblog.com.au
RE: Engineering mistakes
Also, another thread on Engineering mistakes pretty well covers this ground and I think we should make clear a distinction between envelope pushing, unexpected outcomes and "should have known better" mistakes, the web link seems not to make that distinction.
JMW
www.ViscoAnalyser.com
RE: Engineering mistakes
The buiding had the main supports in the center of the walls, not at the corners. This was to preserve an historic church I believe. Applying wind to the corner caused half the braces in the building to unload and the other to recieve double load.
To his credit, the engineer is the one who discovered the problem and brought it to the attention of the proper people. It was and still is an innovative design.
Rik
RE: Engineering mistakes
Some interesting factoids:
h
Near as I can tell, the only stupid engineering mistake was taking the job in the first place. This is clearly a "pushing the envelope" case, coupled with an Admiral ignoring a failed acceptance test, and a captain taking too many risks on a maiden voyage.
TTFN
RE: Engineering mistakes
An example that comes to mind, there was a piece on the Sherman tanks from WWII, which went on and on about how they were so inferiorly designed to the German tanks of the day. Engineering failure this and design failure that. Unless I missed something, the designers and engineers did their jobs to the letter. If they were provided with faulty design inputs, how is that their fault?
For instance, if the customer (US army?) says we need armor to stop a 20mm shell and the designers deliver - is it their fault that the Germans are using 40mm shells? Is this an engineering disaster?
RE: Engineering mistakes
The replenishment rate of US tanks to German tanks was 16:1. For every German tank replaced, the US replaced 16.
The US was fighting on industrial efficiency while the Germans relied on military efficiency.
The US tanks were desgined for superior manufacturing speed, not superior field performance.
The numbers may not be exact, but I believe the relativeness of the numbers are correct.
Then again, this may be an "urban legend", so reader beware.
"Do not worry about your problems with mathematics, I assure you mine are far greater."
Albert Einstein
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RE: Engineering mistakes
JMW
www.ViscoAnalyser.com
RE: Engineering mistakes
"Do not worry about your problems with mathematics, I assure you mine are far greater."
Albert Einstein
Have you read FAQ731-376 to make the best use of Eng-Tips Forums?
RE: Engineering mistakes
Vasa sunk 1628 http://en.wikipedia.org/wiki/Regalskeppet_Vasa
TTFN
RE: Engineering mistakes
The Mary Rose sunk during battle towards the end of her life expectancy. Evidently, she was becoming obsolete as a war ship.
"Do not worry about your problems with mathematics, I assure you mine are far greater."
Albert Einstein
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RE: Engineering mistakes
Evidently, the news hadn't made to Sweden prior to the construction of the Vasa.
TTFN
RE: Engineering mistakes
TTFN
RE: Engineering mistakes
It seems that no other English war ship suffered from this design.
"Do not worry about your problems with mathematics, I assure you mine are far greater."
Albert Einstein
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RE: Engineering mistakes
The Sherman also had to fit in with the loading gage of various bits of transportation. To transport a German tank on the railway first you removed the main drive wheels and the tracks, and then fitted narrow ones. At the other end of its journey you reversed the process. Crazy.
Also notice that the Sherman was basically the well proven chassis of the Lee/Grant, with a new top. That was not the only reason it was reliable, but it was one of the reasons. The chassis of PV and PVI were new each time, and the lack of reliability was crippling. Tanks were gaining weight at a rate of about 30% per year during the war, so one based on an old chassis was likely to be rather light and hence under armoured compared with the clean sheet of paper designs. See
htt
Sherman was not perhaps a brilliant design in retrospect, it was evolutionary not revolutionary, but it was good enough. The Allies made far worse engineering mistakes than the spec of the Sherman.
Cheers
Greg Locock
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RE: Engineering mistakes
Quite the man, in my view. For those of you who have or have not been to Southern California might know that it is a desert, yet it flourishes with the benefit of water provided by the vision and engineering for-site of William Mulholland. He took full responsibility for the failure of the dam. Critics also concede that at the time the technology was limited to ascertain poor conditions of the bed rock. For the rest of us his vision of water canals and aqueduct system to feed Southern California it's water needs was truly genius.
PS: I live in one of the small towns that was devastated by that flood.
Stupid Engineering Mistake or just good viewer ratings.
I'll stand by Mulholland.
Best regards
pennpoint
RE: Engineering mistakes
Is the designer/engineer responsible for validating the appropriateness of the design inputs?
I'm not talking breaking laws of physics, but why is it called an engineering disaster if the end-user did something completely foolish and unanticipated, causing failure?
RE: Engineering mistakes
"Do not worry about your problems with mathematics, I assure you mine are far greater."
Albert Einstein
Have you read FAQ731-376 to make the best use of Eng-Tips Forums?
RE: Engineering mistakes
We get that situation very often in aerospace, particularly since the customer community no longer has the in-depth expertise they used to have.
We have customer now that insists on requiring a laser that puts out nearly double the required power, but also wants it in a small volume and weight, but doesn't want to pay to break the laws of physics and reality.
TTFN
RE: Engineering mistakes
"Do not worry about your problems with mathematics, I assure you mine are far greater."
Albert Einstein
Have you read FAQ731-376 to make the best use of Eng-Tips Forums?
RE: Engineering mistakes
RE: Engineering mistakes
http://
RE: Engineering mistakes
As an aside, one thing that grates is the smug tone of some engineering critiques. As if the critic would never have made such a foolish error! But then, the best way to avoid criticism is to do nothing.
RE: Engineering mistakes
TTFN
RE: Engineering mistakes
Others, such as the Kansas city Hyatt, were just plain irresponisble. Someone should have known better but either didn't check or didn't care. That mistake was preventable and within our realm of knowledge to do so. All you learn from that is how to save a few dollars at the expense of lives, and hopefully we all learn not to do it again.
RE: Engineering mistakes
TTFN
RE: Engineering mistakes
I hear you about the engineering disater shows. I was watching one talking about some houses in CA sliding off a hill. On the show they stated that all the homes that moved were built before engineering was required (ie NO engineering). How is it an engineering disaster, if there was no engineering?
Rik
RE: Engineering mistakes
Purity Distilling Company tank, 1919
This is a topic in the new PE magazine from NSPE and will be a topic at the conference in Boston.