Wikipedia says:

Denver International Airport uses many pneumatic tube systems, including a 25 cm diameter system for moving aircraft parts to remote concourses, a 10 cm system for United Airlines ticketing, and a robust system in the parking toll collection system with an outlet at every booth.

Problem: No citation, and I can't find any reference to it on the web.

My question: Would it be acceptable to post a question asking about this system's size and usage rate, even though I am not sure it actually exists?

UPDATE: Seeing the consensus, I proceeded to post the question.


2 Answers 2


Thank you for posting here.

I'll post my answer from chat also here so that it can be voted upon.

In my opinion, asking if it exists could be on topic, but could receive better answers on skeptics.

As for the usage rate and size, I think it would be on topic, since it is not a question related to the passenger side of aviation.


Asking if something exists seems fine to me, provided that:

  • It's on-topic
  • It's a real-world question, i.e. not about a fictional universe or whatever
  • It isn't sensationalist or a conspiracy theory (that might be OK on skeptics.SE)

So for me, asking if Denver Airport has a pneumatic tube network is fine; asking if it has secret underground bunkers built by the Illuminati is not.


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