The tag is too broad; it reminds me of the now-dead flight tag.

It usage guidance says:

... aerodynamics, flight dynamics, stability and control, aircraft hydraulic and electric systems, engine thermodynamics

All of which have their own tags, as they should, so what's the point of ?

To make my point clearer, with an example: the tag system here is not hierarchical; one of the most popular tags in that usage guidance, , has appeared 1,728 times out of 1,826 without (95% of the time). Further, despite having 299 questions, aircraft-physics appeared on its own only 11 times (SEDE query), and all 11 can be perfectly tagged with more appropriate and well-defined tags.


The usage was ballooned only in 2020, prior to that it was more manageable...

Physics as they apply to aircraft, including aircraft motion, forces affecting an aircraft, and stability and control.

... making it more related to .

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A tag is a word or phrase that describes the topic of the question. Tags are a means of connecting experts with questions they will be able to answer by sorting questions into specific, well-defined categories.

Emphasis mine.

See related: The reason tags become vague, and how we can fix the issue


I agree, is far too broad and it should be removed. The current usage guidance is horrendous. It is essentially inviting every second question to be tagged with it by listing a wide array of topics.

In general however, we may sometimes need higher level tags with some "sub-tags", even if the tag system is not hierarchical. Consider e.g. the tag . This tag could be used for questions about a specific Boeing aircraft, which all have their own tags (e.g. ). But in this case, I think there is a reason to have the more general tag, which should be used for more general questions (about the company, or about Boeing aircraft in general). The specific aircraft tags should then be used for questions about that particular aircraft.

In the case of I cannot imagine a question, which would require such a generic tag without being able to use a more specific one. If we re-tag those 11 questions you have found with more specific ones, can IMHO be removed.


Well, I've been wondering if the tag flight-mechanics is redundant with flight-dynamics and aircraft-physics. But if folks want to "burninate" aircraft-physics, then it seems we need to keep flight-mechanics to deal with discussions of forces acting on aircraft in steady-state situations-- since steady-state situations would seem not to fall under the flight-dynamics tag.

So, what I predict, is that if we "burninate" aircraft-physics, then flight-mechanics will become the new catch-all tag that will become overly broad. Certainly it would seem to also legitimately include anything that could be tagged with "flight-dynamics".

  • $\begingroup$ Re Certainly [flight-mechanics] would seem to also legitimately include anything that could be tagged with "flight-dynamics". -- If you can make a good case for it, i.e. mechanics being the main topic, please submit an answer to Does flight-dynamics encompass flight-mechanics and stability? / Note that you previously stated "... "flight-mechanics" tag should be deleted, and most questions with this tag should be given the "flight-dynamics" tag if they do not have it already." $\endgroup$ – ymb1 Apr 19 at 17:27
  • $\begingroup$ @ymb1 -- yes, I said "most"-- but not "all". And a) that was assuming the aircraft-physics tag wasn't going to go away and b) it's unclear to me whether questions that deal with steady-state situations, such as the forces in a sustained climb, should qualify to be considered "flight-dynamics". If we take the approach that they do, well, ok. That's probably what most people are already doing. Where as I tend to think of dynamics as a subset of mechanics, dealing specifically with non-steady-state situations. $\endgroup$ – quiet flyer Apr 19 at 17:34
  • $\begingroup$ Basically I guess what I'm saying is that "aircraft-physics" and "flight-mechanics" seem almost redundant, but I'm not sure whether "flight-dynamics" is enough to cover everything that might be left without a good tag if we eliminate both. E.g., forces in a steady climb at constant airspeed, is that "flight dynamics"? Not sure. $\endgroup$ – quiet flyer Apr 19 at 17:36
  • $\begingroup$ I understand now, thanks for the explanation. It's something that hopefully someone will address in-depth in the linked post. $\endgroup$ – ymb1 Apr 19 at 17:39
  • $\begingroup$ @ymb1 -- Really I haven't completely made my mind up. I'm not even entirely sure what the most correct usage of the words is, and whether or not it's accurate to say that one is a subset of the other, at least in the context of flight. Googling "dynamics versus mechanics" brings up some interesting results. Maybe "flight-dynamics" is acceptable after all for just about everything labelled w/ "flight-mechanics"-- (e.g. forces in steady-state climb)-- $\endgroup$ – quiet flyer Apr 19 at 17:44
  • $\begingroup$ Isn't steady state usually labelled Fight Performance? $\endgroup$ – Koyovis Jun 9 at 4:30

Should you want to get rid of the tag, we would need to go through the roughly 300 questions with this tag and ensure that they are appropriately tagged. In the past we have made sure that removing the tag leaves at least 2 remaining, which means the list with currently <=3 tags (including the one to be removed) need to be manually "eye-balled" - this is just over half of them.

Here is a useful query to see the scale of the effort required: https://data.stackexchange.com/aviation/revision/1400322/1721644/questions-tagged-aircraft-physics

It's also worth reading this before we go all out: When to burninate

  • 1
    $\begingroup$ thanks for the heads-up and links $\endgroup$ – ymb1 Apr 23 at 16:40

Aircraft-physics, as in physics applied to aircraft?

There have been a few instances where people in the Aviation site placed a comment that a question on hydraulics belongs on the Physics site. So seen from that angle, aircraft-physics would make a tiny bit of sense.

However, the hydraulic systems, electrical systems, radar systems etc. are usually categorised under aircraft-systems. So yeah, aircraft-physics could be done away with. It might be a legacy from the early site days.


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