Ethical question regarding tolerances on test plan
Ethical question regarding tolerances on test plan
(OP)
I'm new to engineering, so I'm looking for the opinions of some more experienced engineers regarding the following ethical concern, which I will phrase as a hypothetical.
Suppose there's an aerospace company that's trying to get a product into the market. There's a specification that defines the required performance, and a test plan that's been approved by the would-be customer as a means of demonstrating compliance with the spec. The spec requires the product perform at a temperature of 100°C, so the test plan calls for the unit to be placed in an oven at 100+/-5°C for three hours (+/- 5 minutes), then removed from the oven and operated within five minutes.
The engineering team discovers that the product will not function satisfactorily at 100°C. Engineer A suggests setting the oven to 96°C, and lowering the temperature of the test stand room to improve the product's chances of passing the test. Engineer A further suggests leaving the unit in the oven for exactly 2 hours and 55 minutes. He further suggests building a "quiescent oven" to use instead of the standard convection oven that the company has always used to test similar products.
The question is: Is Engineer A's proposal ethical?
It will be Engineer B's responsibility to execute the test. If Engineer B's boss says that Engineer A's suggestions should be followed, what should Engineer B's response be?
Suppose there's an aerospace company that's trying to get a product into the market. There's a specification that defines the required performance, and a test plan that's been approved by the would-be customer as a means of demonstrating compliance with the spec. The spec requires the product perform at a temperature of 100°C, so the test plan calls for the unit to be placed in an oven at 100+/-5°C for three hours (+/- 5 minutes), then removed from the oven and operated within five minutes.
The engineering team discovers that the product will not function satisfactorily at 100°C. Engineer A suggests setting the oven to 96°C, and lowering the temperature of the test stand room to improve the product's chances of passing the test. Engineer A further suggests leaving the unit in the oven for exactly 2 hours and 55 minutes. He further suggests building a "quiescent oven" to use instead of the standard convection oven that the company has always used to test similar products.
The question is: Is Engineer A's proposal ethical?
It will be Engineer B's responsibility to execute the test. If Engineer B's boss says that Engineer A's suggestions should be followed, what should Engineer B's response be?





RE: Ethical question regarding tolerances on test plan
Just FYI if I had specked something to perform at 100°C then I'd expect that the minimum temperature used during testing would be 100°C.
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: Ethical question regarding tolerances on test plan
Cheers
Greg Locock
New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?
RE: Ethical question regarding tolerances on test plan
Sorry to peg your irony meter, but I did tell you I'm new at this. It's not from a textbook, but it is against company policy to post details of a real case.
Matt
RE: Ethical question regarding tolerances on test plan
So I guess to put it another way, unless you can get them to put it in writing that the tolerances given are for the testing environment ONLY and are not being given as an actual RANGE across which they're expecting the tests to be conducted, you should be prepared to accept the consequences that may occur if you're assumptions are later questioned as whether you've meet the letter or the intent of the contract.
John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
Siemens PLM:
UG/NX Museum:
To an Engineer, the glass is twice as big as it needs to be.
RE: Ethical question regarding tolerances on test plan
Garth Dreger PE - AZ Phoenix area
As EOR's we should take the responsibility to design our structures to support the components we allow in our design per that industry standards.
RE: Ethical question regarding tolerances on test plan
Apparently an aluminum manufacturer decided they could save money by adjusting alloy content from nominal values of the aircraft sheet metal specification. If you have ever examined the alloy content ranges on such a specification, you know they are quite wide. With better specification control, they realized a more consistent product and increased profits. Meanwhile an aircraft manufacturer that had developed a massive library of strength, fatigue, and other material allowables for the aircraft sheet metal specification started to notice unexpected issues in the field since all their test data was based on the previous alloy properties. Needless to say this caused quite a row...
In your case, the stakes are likely nowhere similar but there are lessons to be learned. Honestly, I would say that Engineer A's approach is more resourceful than unethical and this is more a training/knowledge issue than anything else.
Arbitrary specifications such as this 100°C requirement come about general because past experience has shown them to be reliable. We can "sharpen the pencil" or otherwise try to squeeze into the requirement but in doing so, you really are shaving away from the reliability of the system.
You can go too far the other way as well, adding conservative requirements. One time I was told by an experienced certification guy that he always likes to have the techs drag flammability samples around on the shop floor to make sure they have a good amount of dirt and oils to simulate degradation of the samples in service before testing. Well, that skews things away from the requirements which again have been established as reasonable.
Stick to the nominal.
RE: Ethical question regarding tolerances on test plan
John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
Siemens PLM:
UG/NX Museum:
To an Engineer, the glass is twice as big as it needs to be.
RE: Ethical question regarding tolerances on test plan
Tolerances are for things that can't be controlled.
RE: Ethical question regarding tolerances on test plan
Garth Dreger PE - AZ Phoenix area
As EOR's we should take the responsibility to design our structures to support the components we allow in our design per that industry standards.
RE: Ethical question regarding tolerances on test plan
RE: Ethical question regarding tolerances on test plan
I have a feeling that if my boss was intent on hiding this from the customer, he'd write the test report himself. It's not good when your boss feels he has to do your job for you. On the other hand, gaming the spec creates a culture of dishonesty that could ripple through all the testing we do.
Woodman, if the customer were on board with this, my conscience could rest easy. But I think it's unlikely that "A" or "boss" would agree to tell them, and it's not "B"'s role to inform them.
RE: Ethical question regarding tolerances on test plan
All of the specifications I've seen and used were stated as XXX +/-Y, which is the mean and its tolerance. The customer expected that and not XXX-Y +/-Y. There is a difference because you're stating different means. If your customer expects XXX +/-Y and routinely gets XXX-Y +/-Y, he will eventually tell you your process is out of control and look for another supplier, if he understands manufacturing. For example, some of the parts I've worked on the in past now have a spec of XXX +/-0. They now have to be dead on. XXX-Y +/-Y is far from dead on in some parts. In some other parts, we moved the mean to gain other improvements.
Is it unethical to be ignorant? No. It is unethical to be devious? Yes. Only you know what's going on completely and can provide your ultimate answer.
Engineers should conduct themselves as professionals. You always treat your customer fairly and honestly. That's the right thing to do. If you're looking for guidance here, you know something stinketh and you probably know what it is. Whatever you do take the high road and protect your customer as well as your working relationships. It's nothing personal. It's good business. Through good business and professionalism, you will gain a good reputation and those are hard to get.
Pamela K. Quillin, P.E.
Quillin Engineering, LLC
RE: Ethical question regarding tolerances on test plan
If life safety were involved... talk to your lawyer... you could be criminally responsible.
I don't agree with the methodology, but to the letter of the spec you have achieved a passing grade... this time!
Dik
RE: Ethical question regarding tolerances on test plan
Cheers
Greg Locock
New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?
RE: Ethical question regarding tolerances on test plan
You may need to read carefully a contract. If you guarantee that you will pass the tests you describe, then you must test the device at 105°C for 3 hours and 5 minutes, or whatever the worst case is.
--
JHG
RE: Ethical question regarding tolerances on test plan
RE: Ethical question regarding tolerances on test plan
"On the human scale, the laws of Newtonian Physics are non-negotiable"
RE: Ethical question regarding tolerances on test plan
The test procedure is not compliant, and should not be approved.
Engineer A is a scum bag.
Your warranty costs will be high.
RE: Ethical question regarding tolerances on test plan
The customer should not have accepted those limits as valid. Assuming ±1°C tolerance on the thermometer, the minimum acceptance test temperature should have been 101°C.
I should also warn you that marginal designs may have other flaws. We came across a sensor that was specified for operation up to 100°C, and it operated to spec at that temperature, but failed to operate at 90°C.
TTFN
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RE: Ethical question regarding tolerances on test plan
I don't think the OP ever really answered the question of if the customer approved this test plan or not.
Without having seen the exact wording of the specification the 3 of us are assuming that the 100°C is really a minimum, which seems likely/reasonable, however we don't know for sure.
Certainly if this is right it seems unlikely the customer explicitly approved the test plan, in which case why try to fudge it?
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: Ethical question regarding tolerances on test plan
Do you mind telling me the name of your aerospace company, so that I can avoid buying whatever it is you are selling.
B.E.
The good engineer does not need to memorize every formula; he just needs to know where he can find them when he needs them. Old professor
RE: Ethical question regarding tolerances on test plan
Tobalcane
"If you avoid failure, you also avoid success."
“Luck is where preparation meets opportunity”
RE: Ethical question regarding tolerances on test plan
Tobalcane
"If you avoid failure, you also avoid success."
“Luck is where preparation meets opportunity”
RE: Ethical question regarding tolerances on test plan
Tobalcane
"If you avoid failure, you also avoid success."
“Luck is where preparation meets opportunity”
RE: Ethical question regarding tolerances on test plan
TTFN
FAQ731-376: Eng-Tips.com Forum Policies
RE: Ethical question regarding tolerances on test plan
The test procedure should state something to the effect of "set temperature to 100C" not "set temperature to 100C +/- 5C". The customer should have read and approved the procedure. If you are changing it you need to get their approval again.
Where did you determine that your product would fail the test? Was it during the formal testing? If so then that is a failure already, you don't get to keep trying until you pass. You and your customer would need to get together and determine what to do about the failed test, re-design or spec change.
I assume your customer will also be reviewing and approving the test results, what happens when they see the output of the temp chamber droping well below 95C?
Doug
RE: Ethical question regarding tolerances on test plan
If I were in Engineer B's shoes, I'd stick to the nominal, i.e. how the test plan should have been written, and suggest that the customer be contacted about a waiver. I'd explain this to Engineer A and the boss first, and appeal to my QE and Head of Engineering if needed. My name wouldn't go on any document suggesting that A's test plan demonstrates compliance with the specs. However, I suppose I would conduct any testing I was ordered to, even if I thought they were going to use my test data for evil instead of good.
RE: Ethical question regarding tolerances on test plan
Cheers
Greg Locock
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RE: Ethical question regarding tolerances on test plan
When your boss wants you to do something illegal or unethical, it normally ends up bad for you no matter what.
Your best chance of minimising personal consequences is to play real dumb and claim you don't exactly understand what he wants you to do.
To push the point you can even say (in writing) that you must be misunderstanding his direction as from your interpretation, it seems he is asking you to do something dishonest, so could he please give you written instructions so that you can study them and ensure you are not misinterpreting them.
Keep copies of request and reply at home. Make diary notes of verbal exchanges on the subject.
Regards
Pat
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RE: Ethical question regarding tolerances on test plan
Where I used to work, it was called "keeping a Pearl Harbor file"...
John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
Siemens PLM:
UG/NX Museum:
To an Engineer, the glass is twice as big as it needs to be.
RE: Ethical question regarding tolerances on test plan
I would also think that as you get close to the pass/fail borderline, that there wouldn't be a sharp division, you'd just be changing the percentage pass/fail. So at 100 degrees, maybe 20% of them pass, and at 96, 80% of them pass. Either way, it's not an indicator of good reliability.
RE: Ethical question regarding tolerances on test plan
TTFN
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RE: Ethical question regarding tolerances on test plan
If it is an accelerated life test then you don't really know whether knocking 5 dgerees off the test temperature, and 5 minutes off the oven time, equates to a reduction of X% in real life performance, without performing additional tests. The relationship between real life and accelerated life testing is measured and expensively known, for many systems, but not in the open literature.
Cheers
Greg Locock
New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?
RE: Ethical question regarding tolerances on test plan
I'd ask a couple 5 year olds. You have a pair (of something) and a backbone. Start your career by using as required, people will take notice.
RE: Ethical question regarding tolerances on test plan
Tobalcane
"If you avoid failure, you also avoid success."
“Luck is where preparation meets opportunity”
Perception is reality: You may build your skill set, but what you think of it doesn't really count. The only thing that really matters is what your boss and or customers think of it. Likewise, the real you is how others perceive you, not
RE: Ethical question regarding tolerances on test plan
No.
Test labs follow test procedures.
If the test procedure is ambiguous or poorly written they will do their best, or seek clarification from whoever is paying the bill. If that clarification comes from an unethical or knowledgeable source then it's not clear what will happen.
RE: Ethical question regarding tolerances on test plan
Tobalcane
"If you avoid failure, you also avoid success."
“Luck is where preparation meets opportunity”
Perception is reality: You may build your skill set, but what you think of it doesn't really count. The only thing that really matters is what your boss and or customers think of it. Likewise, the real you is how others perceive you, not
RE: Ethical question regarding tolerances on test plan
Tobalcane
"If you avoid failure, you also avoid success."
“Luck is where preparation meets opportunity”
Perception is reality: You may build your skill set, but what you think of it doesn't really count. The only thing that really matters is what your boss and or customers think of it. Likewise, the real you is how others perceive you, not
RE: Ethical question regarding tolerances on test plan
If there is an end user representative present to witness the testing then usually everyone will defer to his or her decrees. But there is not always an end user representative present, and even when present they may not be the right person to notice that the test procedure is not compliant with "the spec". Often the end user representative is an inspector or junior engineer and all they'll look for is "approval" of the test procedure.