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I've read a lot of answers on this site that make references to various aerospace equations.

So many of these are awesome responses, but I have trouble understanding the math because I don't know what all the symbols in the equation mean, or what units they are referring to.

For example, this question uses the equation below and even has a really cool picture to go along with it:

enter image description here

However when trying to understand the "mass flow" function I didn't see any explanation of what the lowercase "t" variable was.

I am sure this is common knowledge for many people, but are there are any charts out there for amateurs like myself to understand the different symbols commonly used in fluid functions and their implied units?

Or is this really a matter of needing to learn aerospace in general as the equations are too diverse to understand by a symbols cheat sheet?

Pondlife
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YAHsaves
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  • I don't really understand what you are trying to ask: Symbols chart for common aerospace equations is not a question – Super Jul 24 '18 at 00:07
  • Sorry, I edited the question to reflect more what I meant. – YAHsaves Jul 24 '18 at 00:09
  • I would consider you adding a source link for the picture above – Super Jul 24 '18 at 00:14
  • @FallenUser I did, I added a hyperlink to the "for example this question" that leads you back to the question. I'll edit it to make it more obvious – YAHsaves Jul 24 '18 at 00:17
  • Even if they do make it to the question, you should add where it came from as the question with the picture does not – Super Jul 24 '18 at 00:23
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    dm/dt is a derivative function which in this case means the derivative of mass with respect to time. This is basic calculus, not really related to aviation. – Ron Beyer Jul 24 '18 at 01:30
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    Learn physics. Even if we tell you the names, you will not understand it without the underlying concept. – kevin Jul 24 '18 at 02:45

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Unfortunately, the nomenclature used can vary from source to source, and the same variables can even be used for completely different things depending on the context. It is generally good practice for the author to describe the variables they use, but we've all been guilty of skipping that step.

In any case, there are many helpful sites such as See How It Flies or the Aerodynamics Index from NASA that tend to use pretty 'standard' notation. BUT, there is no single cheat sheet that has every variable for every analysis and one should always be careful to double check.

Geoff
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