Aircraft in General - Get Started with Physics and Books

[nefliege]

Hi, I got really interested in aircrafts (aerodynes) recently and I would love to know more about it. But I have no idea where to start. Better to start with some Physics background first (I used to be interested in Physics, but I dropped it like 2 years ago; I'm returning to it now but still have a lot to learn) or buy a good book about airplanes? But, what branches of Physics exactly? What book?
What interests me is mainly the ability to fly (and I guess I'm not alone here ^^) - it means the reason for the lift force as well as what engines are in modern airplanes, but also what are the methodes to keep it from freezing. Heh, generally what I would love to achieve, is that in a year I will look on some NASA contest (like this: http://aero.larc.nasa.gov/era_high/competitions_high_era.htm ) and say: "okay, I'll think about it", instead of thinking "omg, I'm such a failure I don't even even know what fuel consists of..."
I hope you know what I mean..
Thanks for any help :)

 

[Curl]

Classical mechanics and fluid dynamics. I don't know your level so I can't say what book is right for you.

 

[K^2]

There are so many things...

First, there is basic aerodynamics. Understanding of forces on the aircraft. There are forces generated by the engines, lifting surfaces, and the body. They all fall into 4 groups. Lift, drag, thrust, and weight. You need to understand which forces balance which, and what happens when they become unbalanced. Things like why when you reduce thrust, the aircraft begins to descent rather than to slow down. You also need to understand where these forces are applied if you hope to understand stability. When you understand why the tail wing has negative lift, and why flying with aft CG improves performance, but makes stalls more dangerous, you have that part down.

Then there are 3 main categories to understand in more detail. There is material resistances physics, which applied to aeronautics is all about making sure the plane doesn't fall apart in the air. There is the hydrodynamics, which is all about actually figuring out where lift and drag come from. And then there is propulsion, which has some of both of these plus a lot of thermodynamics involved. Each field will require you to learn a bunch of physics first. If you are interested in one of these specifically, I can expand a bit.

 

[nefliege]

Thank you K^2 ! But If I knew where to find those things I wouldn't have asked :( Well, I found one book that is (wow, at least one..) available in my country and that seems fine to me, and this is an excerpt from it: http://home.comcast.net/~clipper-108/lift.htm
Do you think it is a good book? I'd appreciate your opinion, because I don't trust myself enough, to judge on my own if it's a valuable one or just a piece of (you know). And moreover it's not very cheap so I don't want to waste my money if it's not good.
Another thing is that I'd be interested in mathematical description as well, and wonder if it's reasonable to buy two different books.
As for the "three main categories" I sure would be happy to hear more about them but I think it's better that I've known the basis first - I don't want a total mess in my head ;p Could I write you or something if I managed through all those general things described in the first paragraph and still was interested in the whole thing ?

Hmm, my level ? I don't think it's high :( I know only enough for AP level (mechanics C) maybe a little more (I've seen some problems on the internet and they seemed easy, so..), but I know almost nothing about fluid dynmics, except for a few things like Pascal's law or Bernoulli's equation. But I think that if I only had a small hint what exactly to learn I wouldn't be a problem to learn it, I kinda have all the Physics books in the library just for myself; it seems no-one else is interested in them, lolz.

btw, sorry for my poor English, I'm trying to do my best :)

 

[rcgldr]

This website does a good job of providing a simple explantion of the factors involved:

http://www.avweb.com/news/airman/183261-1.html

 

[HossamCFD]

I strongly recommend those three books by John D. Anderson :

1. Introduction to flight : an easy understandable book that requires only a knowledge of high school mathematics. perhaps this is the best place to start

2. Fundamentals of Aerodynamics : If you're interested on the physics and fundamentals of the subject. this is a mathematically-based overview of aerodynamics and it requires a somehow higher level of knowledge in Calculus and tensor analysis. If you care to go through the mathematics, this will probably be one of the most entertaining books that you can find on the subject.

3. Aircraft performance and design : less mathematics and physics but more details about flight dynamics and aircraft in general.Those will indeed get you started.

 

[nefliege]

Thanks rcgldr and HossamCFD :)

Hossam, could I ask you which of the books you recommend the most ? I'd be great to read them all, but they're expensive :( And what do you mean by "higher level" ? thx

 

[HossamCFD]

Hossam, could I ask you which of the books you recommend the most ? I'd be great to read them all, but they're expensive :( And what do you mean by "higher level" ? thx

By "higher level" I meant relative to the other two books.

as for which one to read first, it depends on your background. Introduction to flight is the easiest way to start and it will most likely motivate you to read the whole series. But if you are really motivated to go into a more fundamental level and deal with the physics in a more thorough way I would definitely recommend fundamentals of Aerodynamics. However, it could be very hard if you were not introduced to vector analysis, partial differential equations, and at least an introductory course in fluid dynamics. This book is originally intended to a senior undergrad or junior grad level for mechanical/aerospace engineering.

 

[nefliege]

Okay, after what you wrote, I think I'll buy the "Introduction...", it's safer ;) And also start with learning maths - I guess it's better to check if I'm able to understand such things (like partial differential equations *.*) before buying a book that uses them everywhere ;p
Thanks a lot ! :)

 

[ccrummer]

Congratulations, nefliege, on your quest. In addition to the books by John D. Anderson Jr., there is an excellent book: "Boundary-Layer Theory" by Gersten and Schlichting, and Landa' "Fluid Dynamics." One thing you'll find in your study of subsonic aerodynamic lift is a lot of very fundamental and heated disagreement on what causes it. (Don't be lured into "False Dilemma" thinking. There are several factors that cause lift.) To sort through the conflicting assertions you will come across you should study what has become known as "Critical Thinking." This coupled with some rudimentary knowledge of Classical Mechanics will help you a lot. Also, you should respect your own common sense.

I am a classically trained physicist with some years of experience under my belt so you should give my judgements some weight :-§). Here is an example of arguments for lift that you will find. The website mentioned in a reply above states that the curve of the top of a wing has nothing to do with lift. Barn doors and tin can lids will fly in a wind. You can add to these small jagged rocks, like the sand in a sand storm. Nevertheless, your common sense tells you that no one makes subsonic aircraft with wings made of flat plates much less of jagged stone-shapes. The statement about barn doors flying is true but it is a "Red Herring," that is it has nothing to do with the important reasons subsonic aircraft fly. Read my paper here and please get back to me at charlie.crummer@gmail.com : http://arxiv.org/abs/nlin/0507032 . There is a lot of mathematical stuff but you can skip it if you want. It is mainly there to illustrate a point about the "circulation" of air around a wing.

Look at slow motion videos of birds taking flight (youtube) and http://www.av8n.com/irro/ for starters. Good luck on your quest!