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Introducing the Bush Pilot In Training Podcast! Episode 1: Airspace Classification

I’m adding a podcast. The idea is that I’ll record my study notes so that I can review them in the truck as I’m driving around. If I’m the only one who ever hears them, fine, but I’ll share them with anyone who wants to make use of them.

The first episode deals with airspace classification in Canada.

Here are the show notes:

Airspace Division and Classification

Airspace in Canada can be divided in several ways.

There is southern and northern domestic airspace.

There is the altimeter setting region and the standard pressure region.

There is the southern control area, northern control area and Arctic control area.

There are low level air routes and low level airways.

And, of course, there are the alphabetic divisions from A through to G.

Let’s start with the alphabetic divisions. These divisions are often described, at least in part, as an inverted wedding cake, but my instructor Kate gave me a great mnemonic to help remember them:

A: Always IFR, Always need a clearance and Always 18,000′ and higher.
B: Both IFR and VFR, you need a clearance and its 12,500 to 17,999;
C: Clearance required. Terminal Control areas and associated areas;
D: Don’t need clearance. ATC doesn’t provide separation, but will offer information.
E: Everywhere else.
F: Freaky airspace, meaning, “advisory” or “restricted”
G:Good to go. This is uncontrolled airspace, with no ATC.

So, Class A is IFR, and is always Flight Level 18 and higher, or 18,000′ and higher, up to 60,000′.

Class B is airspace between 12,500 and 17,999. Clearance is required and both IFR and VFR are permitted.

Class C is Terminal Control areas, extensions and associated control zones. Clearance is required. IFR and VFR are permitted. You need a 2 way radio, Mode C transponder an altimeter sensitive to barometric pressure to enter. Although control zones are Class C and go up to 3,000′ AGL, Class C airspace can go to 12,500. NORDO aircraft can only enter with prior permission or in an emergency. Class C becomes Class E when the tower shuts down. If you don’t have a discrete transponder code from ATC you should squawk 1200.

Class D airspace doesn’t require a clearance to enter, but VFR traffic must establish 2 way radio contact with ATC prior to entering. IFR and VFR is permitted, but ATC does not provide separation. ATC can provide information about weather and traffic information, and ATC may instruct VFR traffic to avoid D airspace. Some Class D airspace requires a transponder. VFR traffic must maintain a listeinign watch on the frequency advised by ATC. The no clearance required thing is really the result of ATC not providing separation – giving you clearance kind of implies that they’re maintaining some sort of separation, which in D airspace they are not doing. Class D is used for Terminal Control areas and associated control zones.

Class E allows IFR and VFR traffic. There are no special requirements for VFR traffic. Control Zones that don’t have ATC (ie, the tower is closed) are Class E, as are low level airways. (the dif between low level airways and air routes is that airways have control for IFR traffic). Class E is also used for Control Area Extensions, which is airspace above and surrounding a busy control zone, but still below 18,000. Think of a busy airport that needs a bigger piece of the inverted wedding cake over the aerodrome to control traffic. Thats a control area extension.

Class F, for freaky, means Advisory or Restricted airspace. It is airspace used for flying that requires confinement of the activity, and so when in use airplanes not involved in that activity may have access limited. The restriction can be permanent or temporary. Class F can be controlled or uncontrolled, or both. The activities can be acrobatics, hang gliding, aircraft testing, soaring, military ops, parachuting or training. Monitor 126.7 in Class F uncontrolled airspace and the ATC assigned frequency when appropriate. Maintain extra vigilance.

Class F Restricted airspace is a no go area. It can be temporary or permanent.

Class G airspace is good to go general uncontrolled airspace. Air routes are Class G because, unlike Airways, there is no traffic control. In uncontrolled airspace you should monitor 126.7.

Since we’re on the subject, low level airways start way up – at 2,200 ft AGL, and low level air routes run right down to the ground. They both extend to 17,999, but the alphabetic designation of airways changes with altitude. Up to 12,500 low level airways are Class E. Above 12,500 to 17,999 they are Class B.

Low level air routes start at the ground, run up to 17,999, and are Class G. Air routes do not have traffic control. Airways have IFR traffic control.

Control zones occur around aerodromes to control IFR and VFR traffic. IFR traffic is almost always controlled, so control zones can be B, C, D or E airspace. Control zones start at the surface of the earth generally extend upwards to 3,000′ AGL. This can vary. If an airport is especially busy and requires prior permission to enter if may be designated F airspace.

Terminal control areas usually has a 7 mile radius, but you can also find 5 or 3 mile radius terminal control areas. Terminal control areas are the classic inverted wedding cake shape. They surround a control zone but start at 1,200 AGL with a 12 mile radius. They bump out again at 2,200′ AGL with a 35 mile radius and again at 9,500′ AGL with a 45 mile radius. Pay attention to this especially if you fly around a major airport. You may be in uncontrolled airspace at 9,000′ with a TCA only 500′ above you with heavy IFR traffic.

The Altimeter Setting Region and Standard Pressure Region are next. The Altimeter setting region makes use of altimeter information from altimeter reporting stations. You set your altimeter to the closest station along your route, unless they are more than 150 nm apart, in which case you take the reading from the nearest station, whether its en route or not. The Altimeter Setting Region therefore assumes a lot of altimeter reporting stations, which is why it is restricted to Southern Domestic Airspace up to 18,000. You set the altimeter to the airport setting when you take off, and then re-set as appropriate en route, and set it to the destination aerodrome prior to descent.

The Standard Pressure Setting assumes less altimeter information, and so relies on setting the altimeter to the standard setting of 29.92. It is Northern Domestic Airspace and all domestic airspace over 18,000.

For take off and climb you set the altimeter to airport pressure or elevation. Prior to reaching cruise altitude you set it to 29.92. For descent and landing you set the altimeter to the pressure of the destination aerodrome.

When transitioning from the Altimeter Setting Region to Standard Pressure Region you make the change inside the Standard Pressure Region unless otherwise authorized by ATC.

My name is Rob Chipman and I’m a realtor and pilot based in Vancouver, BC. I AM NOT A FLIGHT INSTRUCTOR AND I AM NOT OFFERING FLIGHT INSTRUCTION! I am sharing my study notes and other things I’ve learned while getting my education as a pilot. You’re welcome to make use of this information, but do not treat it as expert advice.

I really enjoy flying, real estate and the Chilcotin.  My company is Coronet Realty Ltd., located at 3582 East Hastings Street, Vancouver, BC, V5K 2A7. I have a C-150L that I own with two other pilots, based out of Pitt Meadows. Do not hesitate to contact me by email if I can help you do anything, especially if its likely to be interesting or concerns selling remote property in British Columbia.

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