It is very confusing trying to determine the permitted allowance around airports. The DJI map shows different size rings around airports and explains on the video that from the edge of the ring you can fly 20 meters and from there outward it increases by a 15 degree angle. Other sites give a 5 mile radious of no fly zone which wipes out most areas around cities like around where I live. I downloaded an app called Hover and it gives that 5 mile ring even around small runways.
Can someone explain it in simple terms?  Id like to go with the DJI map because the smaller airports are not even marked but what is a simple formula on the 15 degree rise in altitude?

DJI map takes into account of flight path. Radius round airports controlled area from ground upwards, as you get further away the flightpath increases at 15degree angle, so just outside controlled airspace increases at 15 degree angle up wards . Hope that makes sense

This is direct from the FAA website re hobbyists and airports

Airports
Recreational operators are required to give notice for flights within five miles of an airport to BOTH the airport operator and air traffic control tower, if the airport has a tower. However, recreational operations are not permitted in Class B airspace around most major airports without specific air traffic permission and coordination.

Take note that the FAA does not distinguish airports by size - that refers to all airports.

This is what I mean. ask a simple question and I got two conflicting answers.

Our church has a 150 acre ranch about 2-3 miles from a small airport that consists of a few hangars and a runway. I would like to know if I can fly there as long as I stay under 100 or so feet.

Hawkeye54 Posted at 2016-10-31 01:55
Our church has a 150 acre ranch about 2-3 miles from a small airport that consists of a few hangars  ...

Technically, I think you are supposed to notify them.  Once off the ground you are under FAA rules.

Fwiw, I noticed in my AMA magazine that their rules say 3 miles from an airport for RC.  I think Europe has a 3.3 mile radius.  The FAA 5 miles in the USA seems a bit much, especially in high density cities like LA, NYC, etc. where they overlap too much.  Maybe since the AMA is now on an advisory committee with the FAA maybe this will change to something like under 400 feet at 3 miles is okay without contacting tower, field, etc.

Hawkeye54 Posted at 2016-10-31 01:55
Our church has a 150 acre ranch about 2-3 miles from a small airport that consists of a few hangars  ...

You have to ask for permission or you will be flying illegally.

ezdrew430 Posted at 2016-10-31 03:45
You have to ask for permission or you will be flying illegally.

You do NOT have to ask permission. You must NOTIFY. Big difference. The airport cannot tell you no.

bob.lionel.gmai Posted at 2016-10-31 04:06
You do NOT have to ask permission. You must NOTIFY. Big difference. The airport cannot tell you no ...

Makes sense but I live 4 miles from a airport and the DJI Go app says "ask for permission".

I will call them tomorrow to notify them. Thanks everyone for clearing that up. In Caddo Mills it would be like calling Barney and Andy in Mayberry. but ill do it. They fly a lot of sky diving flights out of there.

Hawkeye54 Posted at 2016-10-31 05:23
I will call them tomorrow to notify them. Thanks everyone for clearing that up. In Caddo Mills it wo ...

Hawkeye,

I live 4 miles out from an Airport.... What I do is:
1. Call the tower (Notify)
2. Tell them this is a "Courtesy call regarding a Drone Flight"
3. I'll be flying at "The Address"
4. Altitude lets say 200-300 ft. (Should not exceed 400ft legally)
5. Distance (Should not exceed line of sight)
6. Time of day you will be flying... ie   1:00 pm -  2:00 pm

Some airports will ask additional questions and maybe not.
So far I've been asked for my name once and never even for my FAA reg #....
I also have another airport in a different part of the city that only requires you fill out a 1-2 min Form online that you
submit to the tower (online) and if you don't hear back from them in a few minutes by plone of email, you just
go ahead and take flight. (They don't even want to talk to you). I can already see that there are no set perameters for our flying. For now it appears
the airport control tower will just ask their own basic questions. I have flown as close as 1 1/2 out without any
issues with the towers.... so we'll see how it goes in the future... so far so good! Always notify the tower if within that 5 mile rad., if they have an objection they will let you know.
Fly safe...

Hope this helps... BTY this is in the USA

This air field does not have a tower. I found a couple of sites that have some numbers that I can call. When I fly at my house the App says that an airfield is near by. It just says to fly with caution. It looks like a private air strip a few miles away.

Here is a link to that Hover App I found. It is very helpful.
http://www.hoverapp.io/