I was reading up some in my book and had some questions....

muleywannabe

Pre-takeoff checklist
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What is "AGL" in regards to altitude etc. I was also reading up on airspace etc. That is some tricky stuff. We have a small airport in my town but where I am going to train has a control tower. maybe you guys can give me some pointers/info/advice.
 
Easiest way to see AGL vs MSL:
AGL_MSL_Graphic.GIF
 
Let's use these in a sentence:

"The gopher poked his head Above Ground Level."

"Charley nervously watched the coastal storm forecast, as he wanted to ensure he was above the Mean Sea Level."

"Greg stared at his altimeter, which indicated twenty seven thousand feet. He wondered what his actual elevation was above Mean Sea Level."
 
Muley;
Please don't take this too harshly but it would help your cause a lot if you did just a little reading on your own. I'm not sure what book your reading but every book on aviation fundamentals ( and most other fields of study ) will always define acronyms when they are first introduced. If you skipped past that part google is your friend and the definition showed up in the first couple of citations when I just googled AGL Aviation. If you have a question about what they mean after you have done some research on it then by all means shout it out but please do a little reading first.
 
I agree with John T. All of the major (and not so major) texts doe a good job explaining the fundamental terminology and their accompanying acronyms. Don't forget to check both the ToC and Index (and perhaps glossary) of the text to find the answer to your question.

While we are willing to help as needed, self discovery is more rewarding and you're likely to retain the information better.

PS. Also, questions like this are worth asking of your instructor.
 
I was surprised at how many books with aviation stories, as opposed to textbooks, do NOT define terms. The one that stumped me was IRAN when the writer was telling about getting a hanger queen ready to fly again.

Inspect Replace As Needed.

Hanger queen = a plane that spends long periods of time in a hangar without being flown.
 
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Muley;
Please don't take this too harshly but it would help your cause a lot if you did just a little reading on your own. I'm not sure what book your reading but every book on aviation fundamentals ( and most other fields of study ) will always define acronyms when they are first introduced. If you skipped past that part google is your friend and the definition showed up in the first couple of citations when I just googled AGL Aviation. If you have a question about what they mean after you have done some research on it then by all means shout it out but please do a little reading first.

all good points, I tried to look it up in my book but I think I missed it. as they say, if you dont ask questions, you get zero answers:mad2:
 
What book are you using? I'm betting that the collected wisdom of the group can come up with a better resource for you and that kind of question make better use of our knowledge.
 
Even if you haven't flown with your instructor, you can still ask him what he recommends for you to read, as long as you have an instructor.

It's not a bad idea to read ahead, but some books really are better than others. Still others may be better suited to you specifically or may tie in to your instructor's strategy better.

Just wait until you get to decipher true, absolute, indicated, pressure and density altitudes. They all have their purposes, and it's real easy to describe them badly.
 
I was surprised at how many books with aviation stories, as opposed to textbooks, do NOT define terms. The one that stumped me was IRAN when the writer was telling about getting a hanger queen ready to fly again.

Inspect Replace As Needed.

Hanger queen = a plane that spends long periods of time in a hangar without being flown.

Hangar
 
i went ahead and ordered up some Sporty's online course info to help me out. might as well have a vast knowledge before I even step into control. I have flown a lot of hours in a private airplane with friends but never taken control
 
I was surprised at how many books with aviation stories, as opposed to textbooks, do NOT define terms. The one that stumped me was IRAN when the writer was telling about getting a hanger queen ready to fly again.

Inspect Replace As Needed.

I've been wondering that forever. I've been a pilot for a few years, read all about aviation before that, and still never came across any definition of that acronym! Thanks much :)
 
There are a ton of acronyms used in Aviation (and all trades/professions/industries/etc...) that people use without thinking about the effectiveness of the communication.

Even a simple one like AGL can be assumed to be so widely understood, that it may not be defined in a text, or just once on a page that was stuck to another page with bubble gum. Stuff happens.

Aviation might be the worst area for sticking acronyms in places (other than medical) that don't really need acronyms. Think about how much time is wasted on the weather, attempting to learn acronyms and shorthand that is a legacy from the days of telegraphs and Morse code.

OP, you'll be fine. Keep asking questions, good on you for reading ahead of your lessons. Enjoy the learning and discovery.
 
What book are you using? I'm betting that the collected wisdom of the group can come up with a better resource for you and that kind of question make better use of our knowledge.

Great book to have (even if you go with another) is this one (click the image). And the author is one of our beloved curmudgeons here
stickpoke.gif
Bob G.
poking-with-stick-smiley-emoticon.gif


 
I like the way John King puts it.

"MSL is what your altimeter will say when you crash into a radio tower. AGL is how far you are going to fall."

Followed by that weird eye thing he does and a wink that makes me a little uncomfortable.
 
Aviation might be the worst area for sticking acronyms in places (other than medical) that don't really need acronyms.
Keep asking questions, good on you for reading ahead of your lessons. Enjoy the learning and discovery.

The nuclear industry is also pretty bad about the use of acronyms too. :eek:

I also compliment you on wanting to read and study as much as possible about aviation even though you have not started formal lessons yet. As others have said, do your homework first. If you still have questions don't hesitate to ask.
 

I did spell it correctly once in my post. Consistency is the hobgoblin of small minds said somebody. Looked it up on Google: "A foolish consistency is the hobgoblin of little minds." Ralph Waldo Emerson
 
I like the way John King puts it.

"MSL is what your altimeter will say when you crash into a radio tower. AGL is how far you are going to fall."

Followed by that weird eye thing he does and a wink that makes me a little uncomfortable.

Too bad that's wrong.

Your altimeter will only read MSL if set to a nearby station AND at standard temperature (or on the ground at the station).
 
For those of us under FL180 that is what we do. Isn't the ATIS telling me 29.86 telling me what to set my altimeter to so that it it telling me my alt MSL?
 
For those of us under FL180 that is what we do. Isn't the ATIS telling me 29.86 telling me what to set my altimeter to so that it it telling me my alt MSL?

Nope. Only at standard temperature, or at the field it was measured.

It will guide you to a landing and it's appropriate for airspace boundaries, but give yourself a lot of margin if using it to clear mountain passes with temperature far from standard.

See your favorite book on altimeter error (the AIM even has a short section). Here's my favorite: http://www.av8n.com/how/htm/atmo.html#sec-h-a-l-t
 
Well wait a minute, the ATIS / AOS has to be taking temp into account or each station would always give me the same alt setting.

I will read that link after I eat dinner but I may need the layman's version as well. I really thought my airport is 643 feet above sea level so I set my altimeter to 643 prior to taking off so it would measure my alt MSL.

learnin.
 
Well wait a minute, the ATIS / AOS has to be taking temp into account or each station would always give me the same alt setting.

I will read that link after I eat dinner but I may need the layman's version as well. I really thought my airport is 643 feet above sea level so I set my altimeter to 643 prior to taking off so it would measure my alt MSL.

learnin.

It does take it into account, but that only works at the airport altitude. The basic problem is that at lower than standard temperature, the "flight levels" contract physically and the altimeter reads higher than it really is, with an error magnitude that increases roughly linearly with the altitude above the airport (assuming fixed deviation from standard). You can make it right at one point -- and this is done by AWOS/ASOS/ATIS/etc. -- but the geometric altitude changes at a rate different from 1"/1000 feet.

I think it's best described in the Instrument Flying Handbook, as this is of rather obvious importance in instrument conditions when it's cold as ****, when you can't look out the window and see the mountain (or tree or transmission line or other obstruction) is closer than you thought. If you have access to one of Machado's books, he can explain anything.

We're all learning. I went through the same "WTF" shortly after my check ride, when I started studying instrument ground material.
 
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Hi Muley, I'm a student pilot right now. I did a lot of reading before I started flying and it definitely helped, but I wish I had done more.

Recommeded reading:
-Rod Machado's "Private Pilot Handbook" makes everything simple. I could have saved myself a lot of time reading other books if I had read this first. I had a hell of a time learning about engines and this is the book that made sense. (Plus, some corny humor. Every time I turn on the carb heat I remember his line about upside down toilets)
-ASA had "Private Pilot Handbook Volume 2: Ground School," which was dull but thorough.

Also, lots of CFI's have posted videos on youtube which can be helpful. The UND Aerocast has some good ones.
 
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Pod Cast Suggestion: Jason Miller's "The Finer Points"
 
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