Instruments ILS Question

"If during an ILS approach in IFR conditions, the approach lights or any portion of the runway environment are not visible upon arrival at the DH, the pilot is..."

I see why it looks like you could read this both ways, but to me the only interpretation that makes sense is "if none of these things are visible, then ...".

If you don't interpret it that way, then you are left with "if the approach lights are not visible OR any portion of the runway environment is not visible." In other words, if you can't see everything. And it clearly makes little sense in the context to ask "If during an ILS approach in IFR conditions, there exists any portion of the runway environment which is not visible upon arrival at DH, then ...".
 
The "or" combined with "any" combined with "not" makes it ambiguous.
This is such a great way of putting it, thanks.

I would switch it to
A is approach lights visible
B is runway environment visible
M is go missed

I would read the original question as If NOT (A or B) then M. The "reworded" version would be If NOT (A and B) then M, which would mean you'd have to see both to not go missed.

My logic could be flawed but I think it is sound and it's my reasoning for why I think the original question and answer are clear to me.
I asked a random person on the internet sitting in a logic discussion channel (yes they do seem to exist haha) and he agreed with my interpretation on this issue, for what that's worth. Ultimately, what people in logic channels think does not affect my exam, but it's nice to see some pattern to who does or doesn't agree with a given interpretation.

Sheesh, I hate how you two turn it into, math. It's English! Runway environment has more than one portion, right? If you don't have any portion in sight, EXECUTE the missed approach (as in "kill it", please don't say "go missed"—it sounds so sissyish :p).
English and math are both based on logic. I really should say logic vice math to be more clear. You can't write well in English without understanding logic, and you can't analyze complicated sentences using words like "if", "and", "or", "not", etc., without using logic.

grammarteachersofamerica.com is the website you're looking for to address this question.
I think it's necessary to get the perspective of actual pilots due to the effect knowledge of the subject matter has on how the reader interprets the question. In fact, I seem to be getting different reactions from users here vs non-pilots elsewhere regarding what the question is asking. Many people here think the question unambiguously is asking about the case where you see neither the approach lights nor the rest of the runway environment, whereas non-pilots seem to think the question is asking about if you can't see at least one of the list items. To be fair, the non-pilots I've spoken to are biased in other ways. What this might show is that the poor wording of the question is discriminatory and could explain why likely most of the examinees get the question right. After all, it's a very easy question if you read it the way the author intended.

Yes they are. If someone has OCD, they could have changed the question to "...If during an ILS approach in IFR conditions, the approach lights or any other portion of the runway environment are not visible upon arrival at the DH, the pilot is..."
This I believe is explained by the origin of the question. After I made this thread I searched and found a shorter version of the question from what I presume is the FAA database, reposted in to exams4pilots. The wording of the question is "If during an ILS approach in IFR conditions, the approach lights are not visible upon arrival at the DH, the pilot is..." Presumably, someone recognized the question is wrong since the regulations do not require you to see the approach lights more so than any other of the listed items in Part 91, so they attempt to add a few words to patch up that hole. The problem is, it doesn't really make sense to separate out the approach lights from the runway environment since as you said the approach lights are part of the runway environment. This implies there is a reason why they are being separated out, even though with hindsight there isn't one, and this creates yet another source of confusion for the reader such as myself. Ravioli also identified this above.
Maybe. But I used to have a coffee cup that, among other sayings, said "Make it possible for programmers to write in English and you will discover that programmers cannot write in English." It applies to lots of otherwise entirely capable technical folks.
On this topic I'll mention that although my computer programming experience is quite modest (at least compared to a professional), I do a tremendous amount of technical writing for work, and I'm very specific and very clear about the meaning of all of my words... especially words like "or", "and", "not", etc. Admittedly, these technical documents do not make for enjoyable reading as far as writing style goes, and I would have to change up my style of writing if I wanted to write a fictional novel. However, the writing style I use at work is infinitely more appropriate to use when writing exam questions then the writing style used by novelists. There may be exceptions for non-technical exams, but here we are talking about flying planes and instruments, of course.

I see why it looks like you could read this both ways, but to me the only interpretation that makes sense is "if none of these things are visible, then ...".

If you don't interpret it that way, then you are left with "if the approach lights are not visible OR any portion of the runway environment is not visible." In other words, if you can't see everything. And it clearly makes little sense in the context to ask "If during an ILS approach in IFR conditions, there exists any portion of the runway environment which is not visible upon arrival at DH, then ...".
I don't agree that the alternate interpretation results in a question that makes little sense. It's completely valid to want to test to see if the pilot realizes it's okay for them to not see one or two of the required items so long as they can see others. The question isn't very well worded to test that, but it wasn't very well worded to test the other concept of, "execute a missed approach if you can't see anything" so, without hindsight, I think it's difficult to argue the examinee should just reason their way through which interpretation results in a question that tests knowledge that is more reasonable. The multiple sources of ambiguous wording just needs to be corrected before the question is used on a real exam.
 
Real world:

If you see any one of the following prior to or at DH: (list) Then
- - - Drop below DH.
Else you can't see any of the (list)
- - - go missed.
End If
 
Yeah, that has been my understanding since the day I first learned how precision approaches work. It's pretty easy to write clear questions that test your knowledge on that topic. Alas.
 
To be clear, my comment about writing in English was referencing the test authors not your understanding.
 
I would caution some that the regulation says the approach light system must be distinctly visible and identifiable.
 
To be clear, my comment about writing in English was referencing the test authors not your understanding.
Ah okay, thanks. Writing tests is hard so I do have a bit of sympathy, but you are also completely right.

I would caution some that the regulation says the approach light system must be distinctly visible and identifiable.
https://www.law.cornell.edu/cfr/text/14/91.175
"at least one of the following visual references for the intended runway is distinctly visible and identifiable to the pilot" and approach light system is one of the ten available options. Are you thinking of a different regulation?
 
Ah okay, thanks. Writing tests is hard so I do have a bit of sympathy, but you are also completely right.


https://www.law.cornell.edu/cfr/text/14/91.175
"at least one of the following visual references for the intended runway is distinctly visible and identifiable to the pilot" and approach light system is one of the ten available options. Are you thinking of a different regulation?

No, but seeing approach lights does not meet the regulator requirements. The pilot has to see and identify the light system.
 
Admittedly, these technical documents do not make for enjoyable reading as far as writing style goes, and I would have to change up my style of writing if I wanted to write a fictional novel. However, the writing style I use at work is infinitely more appropriate to use when writing exam questions then the writing style used by novelists. There may be exceptions for non-technical exams, but here we are talking about flying planes and instruments, of course.
Speaking of writing style, yours reminds me of someone who wanted to learn to fly in a Learjet about four years ago: https://www.pilotsofamerica.com/community/threads/the-road-to-my-your-own-learjet.73702/
 
t require any changes? Is 'going missed' the best answer but the wording is confusing? Do you consider 'go missed' to simply be a wrong answer to the question?

Overall, a fair number of questions on the FAA exams have poor or ambiguous phrasing. They cover that with the choose the closest to correct phraseology.

This is interesting parsing, but one needs to get used to these problems when dealing with the FAA tests and regulations.
 
Well here's an example of a similar poorly written question but without the grammar issue that OP's question had.

If during an ILS approach in IFR conditions, the approach lights are not visible upon arrival at the DH, the pilot is
A) permitted to continue the approach and descend to the localizer MDA.
B) permitted to continue the approach to the approach threshold of the ILS runway.
C) required to immediately execute the missed approach procedure.


The approach lights are not required for descent below DH, but we can infer from the question and available answer choices that none of the other items that make up the runway environment are in sight either. No matter how the question is worded as to what's in sight or not, A and B would not be correct answers. As someone else pointed out, that's why we're asked to choose the "best" answer. Not the "universally true and completely correct" answer. Such is usually the nature of multiple choice tests.
 
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