Can I fly in controlled airspace?

Know whether the airspace you intend to use is controlled, and what you need before you fly in it.

Controlled airspace is where the answer to "may I fly here?" stops depending on your certificate and starts depending on somebody else's authorization — and where the accuracy of the position and altitude your aircraft reports becomes part of the question. CAR 901.14 Std 922.04

• You can read an aeronautical chart well enough to identify controlled airspace, or you have another way to establish the airspace class over your site.
• You know that the authorization comes from the provider of air traffic services, not from Transport Canada. CAR 901.71
• You know whether you are operating under Division IV (Basic) or Division V (Advanced), because the route to authorization differs. CAR 901.14

No pilot may operate a remotely piloted aircraft in controlled airspace except in accordance with one of two provisions:

• subsection 901.71(1), in the case of an operation conducted under Division V; and
• a special flight operations certificate — RPAS, in any other case. CAR 901.14

The structure is worth reading slowly. There is no third route and no discretion. If the airspace is controlled, you either hold the ATS authorization that Division V provides for, or you hold an SFOC.

No pilot may operate in controlled airspace under Division V unless an authorization has been issued by the provider of air traffic services in the area of operation. CAR 901.71

Note who issues it: NAV CANADA, as the air traffic services provider, not Transport Canada. The distinction matters when you are trying to find out how to apply.

The provider may request information, and the section lists what that can include: the date, time and duration of the operation; the category, registration number and physical characteristics of the aircraft; and further operational detail. CAR 901.71

Have these to hand. An authorization request that cannot state the aircraft's registration number or its physical characteristics is not a complete request.

A pilot must ensure the appropriate ATS unit or user agency is notified immediately any time the aircraft is no longer under the pilot's control and inadvertently enters, or is likely to enter, controlled airspace. CAR 901.15

Three things about that sentence:

• the trigger is losing control and entering or likely entering — the section does not wait for the aircraft to actually cross the boundary;
• the notification must be immediate;
• the duty is on the pilot to ensure notification, so delegating it does not discharge it.

No pilot operating a remotely piloted aircraft may cause the aircraft to leave Canadian Domestic Airspace, unless the operation is conducted under an SFOC — RPAS. CAR 901.13

Authorization is about permission. Standard 922.04 is about the aircraft: for remotely piloted aircraft operating in controlled airspace it requires that design requirements be met so that position and altitude can be communicated to air traffic controllers and other participant aircraft with the specified level of accuracy. Std 922.04

The intent is stated plainly — other users of the airspace should be accurately aware of any potential hazard the aircraft may pose. Std 922.04

Two numbers carry the requirement:

Measurement	Minimum accuracy
Position	± 10 m Std 922.04
Altitude	± 16 m, using the WGS-84 geodetic datum Std 922.04

Neither number is hard for modern GNSS in the open. What matters is where they fail. Position accuracy has to be maintained in degraded modes of operation and across all portions of the proposed operational space — buildings, trees and valleys are the examples given — and the accuracy achieved should be clearly identified in the limitations portion of the operating manual. For altitude, the design has to take account of the differences between ground level, sea level and the various geodetic datums. Std 922.04

The standard says out loud what is easy to forget: accuracy is a probabilistic measurement based on assumptions about quality and integrity in a constantly changing environment. Understanding the errors that degrade it is part of the design, and they belong in an overall error budget. Std 922.04

Source	What it is
Terrain	Masking by a building or mountain blocks the antenna; signals reflected off the landscape arrive as "additional" signals and create position errors Std 922.04
Atmospheric	The ionosphere and troposphere both refract GNSS signals. Tropospheric moisture causes errors up to 6 m; ionospheric refraction may reach 40-60 m by day and 6-12 m at night Std 922.04
Satellite	Poor or unexpected geometry, the gravitational pull of the Sun and Moon moving a satellite from its planned orbit, and solar radiation creating interference before the signal reaches the atmosphere Std 922.04
Geometric dilution of precision	No adequate cross-cut in the fix — the satellites sit too close together — so every signal is vulnerable to the same atmospheric errors. It can occur horizontally, vertically and in time Std 922.04

The atmospheric row carries the numbers worth remembering, and it comes with named mitigations: multi-frequency receivers, selection of a masking angle, and augmentation systems, whether ground-based such as LAAS or space-based such as EGNOS. Std 922.04

Note the shape of the whole standard: it does not ask the pilot to measure anything. It asks that the aircraft's design account for these errors, so that the position and altitude reported to everyone else are the position and altitude the aircraft is actually at. Std 922.04

Two different questions live behind "is it controlled?", and the Regulations answer them in two different sections.

The types. Controlled airspace consists of the Arctic, Northern and Southern Control Areas; high level airspace; high level airways; low level airspace; low level airways; fixed RNAV routes; terminal control areas; military terminal control areas; control area extensions; transition areas; control zones; restricted airspace; advisory airspace; military operations areas; and danger areas. CAR 601.01

Uncontrolled airspace consists of high level airspace; low level airspace; high level air routes; low level air routes; fixed RNAV routes; restricted airspace; advisory airspace; military operations areas; and danger areas. CAR 601.01

Read the two lists side by side and one thing stands out: high and low level airspace, fixed RNAV routes, restricted airspace, advisory airspace, military operations areas and danger areas appear in both. The name of the type does not decide it — the designation of that particular volume does. CAR 601.01

The class. The class of controlled airspace is Class A, B, C, D or E, or Class F Special Use Restricted or Class F Special Use Advisory, as specified in the Designated Airspace Handbook. The class of uncontrolled airspace is Class G, or Class F Special Use Restricted or Class F Special Use Advisory, as specified in the same Handbook. CAR 601.02

What the class changes for a VFR aircraft. The classes have their own entry rules, and two of them are worth knowing because a remotely piloted aircraft shares the airspace:

Class	What a VFR aircraft must do before entering
Class C	Receive a clearance to enter from the appropriate ATC unit CAR 601.08
Class D	Establish two-way radio contact with the appropriate ATC unit CAR 601.09

Both classes make an allowance for an aircraft not equipped with two-way radio: it may enter during daylight in VMC if it receives authorization from the ATC unit before entering. CAR 601.08 CAR 601.09

And both carry a sentence that changes the airspace underneath you without moving it:

Class C airspace becomes Class E airspace when the appropriate air traffic control unit is not in operation. CAR 601.08

Class D airspace becomes Class E airspace when the appropriate air traffic control unit is not in operation. CAR 601.09

So the same volume can be Class C by day and Class E in the evening, and the class is what decides whether an authorization is required at all. Establish the class for the time you are flying, not for the time you planned. CAR 601.08 CAR 601.09

The AIM states the access rule as a list of three conditions, all of which must be met to gain access to controlled airspace: AIM 3.2.3 AIM 3.2.3

Condition	What satisfies it
The pilot	Holds a pilot certificate — RPA (VLOS) — advanced operations AIM 3.2.3
The aircraft	The manufacturer has declared that the unit meets the appropriate safety assurance profile AIM 3.2.3
The flight	The pilot has received an authorization from the appropriate ANSP AIM 3.2.3

Read the first row against the question it is designed to catch: a basic operations certificate never suffices, no matter what the pilot's experience or the equipment is. And read the three together: the authorization is one condition, not the whole of it — an authorization for an aircraft whose manufacturer has not made the declaration does not complete the set. AIM 3.2.3

For the purposes of RPAS operations, the AIM defines controlled airspace as Class A, B, C, D and E, and notes that Class F airspace can be controlled airspace, uncontrolled airspace, or a combination of the two. AIM 3.2.3

Then each class, in the AIM's descriptions, which is where the examinable differences sit:

Class	The AIM's description
A	High-level: from FL 180 in Southern Domestic Airspace, FL 230 in Northern, FL 270 in Arctic. Operating there requires specific authorization from both Transport Canada and NAV CANADA, and it is not denoted on aeronautical charts — the AIM adds that it is rarely a concern for small RPA pilots. AIM 3.2.3
B	Low-level controlled airspace, generally between 12,500 ft and the floor of Class A — but it may include some control zones and control areas that are lower. Authorization from both Transport Canada and the ANSP; the dimensions are in the DAH. AIM 3.2.3
C	Generally around large airports, from the surface to 3,000 ft AGL, with the exact size and shape set by local airspace management needs. AIM 3.2.3
D	Generally around medium-sized airports, also from the surface to 3,000 ft AGL. AIM 3.2.3

And one rule that changes the answer as you read it. Class C becomes Class E controlled airspace when the appropriate air traffic control unit is not in operation, CAR 601.08 and Class D becomes Class E in the same circumstances. CAR 601.09 So "which class is this?" is a question about the time of day as well as the place, and a chart or tool that shows Class C at midday may not describe the airspace you are entering at night. CAR 601.08 CAR 601.09

Both are depicted on VFR Navigation Charts and VFR Terminal Area Charts, and in the DAH through NAV CANADA's drone flight planning tool and the NRC drone site selection tool — which is where a pilot should be looking rather than at a paper chart alone. AIM 3.2.3

Four practical questions sit under this lesson, and the AIM answers each in a place a candidate has to know to look.

Which airspace am I in? That is settled before the flight, in the site survey. The AIM's list of what must be defined for the area of operation includes the airspace classes and applicable regulatory requirements, the routes and altitudes to be followed for the entire operation, the proximity of traditional aircraft and aerodromes, and the minimum separation distances from persons — alongside operation boundaries, obstacles, weather, an alternate landing site and the aviation maps and symbols. AIM 3.2.15 CAR 602.146

The AIM names the resources for it rather than leaving the pilot to guess: the Drone Site Selection Tool, the NAV Drone Viewer, the Canada Flight Supplement, the aeronautical charts of the area, and the Designated Airspace Handbook. The two charts worth knowing are the VNC, at 1:500 000 for low- to medium-altitude flight, and the VTA, at 1:250 000 for the most congested airspace in Canada — and the CFS is updated every 56 days, which is the reason a chart from last year is not a source. AIM 3.2.15

How high may I go? In uncontrolled airspace the limit is normally 400 ft AGL, or 100 ft above the tallest obstruction within 200 ft laterally — unless an SFOC — RPAS states a maximum higher or lower than that. In controlled airspace the maximum altitude for a specific flight is determined by the ANSP, in most cases NAV CANADA — and the AIM adds the constraint that survives every authorization: the pilot must keep the aircraft in VLOS at all times, regardless of the altitude the ANSP allows. Most small RPAs are not visible above 400 ft AGL even in good conditions, which is what makes that constraint bite. AIM 3.2.13

The AIM also warns about the unit underneath the number. Remotely piloted aircraft usually display altitude above ground level from the launch site, while traditional aviation works in above sea level — the AIM's own illustration being that a 400 ft AGL limit near Calgary is roughly 4 000 ft ASL, because the airport sits at 3 600 ft, whereas near Tofino the two nearly coincide at about 80 ft. An RPA pilot monitoring an ATC frequency is listening to altitudes in a different reference frame. AIM 3.2.13

What about the airport next door? Operations inside 3 NM of the centre of an airport, or 1 NM of a heliport, are prohibited to basic certificate holders and reserved for advanced or level 1 complex certificate holders. The distance and the certificate are one rule, not two. AIM 3.2.35

And one more airspace that needs permission rather than a class. Transponder airspace sits beside controlled airspace in the rules for a reason, and the AIM states the requirement for both: an RPA needs authorization from the air navigation service provider — NAV CANADA for civil-controlled airspace, or the Department of National Defence for military-controlled airspace — before operating in controlled or transponder airspace. Small remotely piloted aircraft are not typically equipped with transponders, which is exactly why the question is asked and why the authorization is the answer. AIM 3.2.34

And one trap worth naming here. The aerodrome operating rules a candidate may have read in Part VI — the general aerodrome section, and the provisions that follow it — sit in Part VI, Subpart 2, and that subpart does not apply in respect of remotely piloted aircraft. Seeing a section quoted is not the same as being bound by it. CAR 602.01 CAR 602.96

The AIM's advanced-operations pages carry the same conditions from the operation's side: an advanced operation in controlled airspace requires the safety assurance declaration (SAD) for the type of operation and the distances from people under section 901.194, and compliance with the permitted operation under 901.69. AIM 3.4.1 AIM 3.4.1

You may fly only when all of the following hold:

• You have established whether the airspace over your site is controlled CAR 901.14
• If controlled and flying under Division V, you hold an ATS provider authorization CAR 901.71
• If controlled and not under Division V, you hold an SFOC-RPAS CAR 901.14
• You can supply the date, time, duration and the aircraft's category, registration number and physical characteristics CAR 901.71
• You know how to notify the ATS unit immediately if control is lost and the aircraft may enter controlled airspace CAR 901.15
• The flight will not leave Canadian Domestic Airspace, or is under an SFOC CAR 901.13
• The system's design meets the 922.04 minima: position within ± 10 m and altitude within ± 16 m Std 922.04
• That accuracy holds in degraded modes and across the whole operational space, and is stated in the manual's limitations Std 922.04

Situation	What applies
Basic operation, airspace is controlled	SFOC-RPAS required CAR 901.14
Advanced (Division V) operation, airspace is controlled	Authorization from the ATS provider CAR 901.71
Any operation, airspace uncontrolled	These provisions do not bite
Loss of control with a likely entry into controlled airspace	Notify the ATS unit immediately — do not wait for it to enter CAR 901.15
Aircraft would cross into US airspace	Prohibited without an SFOC-RPAS CAR 901.13
Design accuracy for controlled airspace	Position within ± 10 m: altitude within ± 16 m on WGS-84 Std 922.04
GNSS accuracy at your site	Degraded by terrain, atmosphere, satellite geometry and DOP — the standard's error sources Std 922.04
Which types are controlled	The list in 601.01(1); several types also appear in the uncontrolled list CAR 601.01
Which class a volume is	A to E, or Class F restricted or advisory, per the Designated Airspace Handbook CAR 601.02
Class C entry, VFR	A clearance to enter before entering CAR 601.08
Class D entry, VFR	Two-way radio contact established before entering CAR 601.09
When the control unit is not operating	Class C and Class D become Class E CAR 601.08 CAR 601.09

Symptom	Likely cause	What to do
You applied to Transport Canada for airspace access	The authorization is issued by the ATS provider	Apply to NAV CANADA CAR 901.71
You hold an Advanced certificate and assumed that was enough	The certificate is the prerequisite, not the authorization	Obtain the ATS authorization as well CAR 901.71
You lost control and it drifted toward a control zone	The duty is to notify immediately, not after recovery	Notify the ATS unit at once CAR 901.15
You cannot say what class your site is	Everything in this lesson depends on that answer	Establish it from a chart or an authoritative source before planning
You planned for Class C but are flying in the evening	Class C becomes Class E when the ATC unit is not in operation	Establish the class for the time of the flight CAR 601.08
You assumed a restricted area is controlled airspace	Restricted airspace appears in both the controlled and uncontrolled lists	Look up that volume in the Handbook CAR 601.01
You treated Class C and Class D entry the same	One needs a clearance, the other radio contact	Get the clearance for C, establish contact for D CAR 601.08 CAR 601.09
Your manual never states a position accuracy	922.04 expects the achieved accuracy to be identified in the limitations	Establish it before planning controlled-airspace work Std 922.04
You assumed GNSS is equally accurate everywhere on site	Terrain masking, atmospheric refraction, satellite geometry and DOP all vary	Plan the operational space around those errors Std 922.04

Practise: Operations in controlled airspace

• AIM RPA 3.2.13 — Maximum Altitude

• AIM RPA 3.2.15 — Site Survey

• AIM RPA 3.2.35 — Operations At or In the Vicinity of an Aerodrome

• CAR 602.96 — General (Part VI Subpart 2 — context, not an RPA duty)

• CAR 901.13 — Prohibition — Canadian Domestic Airspace

• CAR 901.14 — Controlled Airspace

• CAR 901.15 — Inadvertent Entry into Controlled Airspace

• CAR 901.71 — Operations in Controlled Airspace

• CAR 601.01 — Airspace Structure

• CAR 601.02 — Airspace Classification

• CAR 601.08 — VFR Flight in Class C Airspace

• CAR 601.09 — VFR Flight in Class D Airspace

• Standard 922 s.922.04 — Operations in controlled airspace

• AIM RPA 3.2.3 — Airspace (the three conditions and the airspace classes)

• AIM RPA 3.2.3 — Airspace (the corpus carries this page under two ids; the bank cites both)

• Consolidation: CARs current to 2026-09-21