ENR 1.4  ATS AIRSPACE CLASSIFICATION AND DESCRIPTION

   ENR 1.4.1 ATS AIRSPACE CLASSIFICATION

ATS airspaces are classified and designated in accordance with the following:


Class A: IFR flights only are permitted. All flights are provided with ATC service and are separated from each other. Continuous air-ground voice communications are required for all flights. All flights shall be subject to ATC clearance.


Class B: IFR and VFR flights are permitted. All flights are provided with ATC service and are separated from each other. Continuous air-ground voice communications are required for all flights. All flights shall be subject to ATC clearance.


Class C: IFR and VFR flights are permitted. All flights are provided with ATC service and IFR flights are separated from other IFR flights and from VFR flights. VFR flights are separated from IFR flights and receive traffic information in respect of other VFR flights and traffic avoidance advice on request. Continuous air-ground voice communications are required for all flights. For VFR flights a speed limitation of 250 kt indicated airspeed (IAS) applies below 3 050 m (10 000 ft) AMSL, except where approved by the competent authority for aircraft types, which for technical or safety reasons, cannot maintain this speed. All flights shall be subject to ATC clearance.


Class D: IFR and VFR flights are permitted and all flights are provided with ATC service. IFR flights are separated from other IFR flights, receive traffic information in respect of VFR flights and traffic avoidance advice on request. VFR flights receive traffic information in respect of all other flights and traffic avoidance advice on request. Continuous air-ground voice communications are required for all flights and a speed limitation of 250 kt IAS applies to all flights below 3 050 m (10 000 ft) AMSL, except where approved by the competent authority for aircraft types, which for technical or safety reasons, cannot maintain this speed. All flights shall be subject to ATC clearance.


Class E: IFR and VFR flights are permitted. IFR flights are provided with ATC service and are separated from other IFR flights. All flights receive traffic information, as far as is practical. Continuous air-ground voice communications are required for IFR flights. A speed limitation of 250 kt IAS applies to all flights below 3 050 m (10 000 ft) AMSL, except where approved by the competent authority for aircraft types, which for technical or safety reasons, cannot maintain this speed. All IFR flights shall be subject to ATC clearance. Class E shall not be used for control zones.


Class F: IFR and VFR flights are permitted. All participating IFR flights receive an air traffic advisory service and all flights receive FIS if requested. Continuous air-ground voice communications are required for IFR flights participating in the advisory service and all IFR flights shall be capable of establishing air-ground voice communications. A speed limitation of 250 kt IAS applies to all flights below 3 050 m (10 000 ft) AMSL, except where approved by the competent authority for aircraft types, which for technical or safety reasons, cannot maintain this speed. ATC clearance is not required.


Class G: IFR and VFR flights are permitted and receive FIS if requested. All IFR flights shall be capable of establishing air-ground voice communications. A speed limitation of 250 kt IAS applies to all flights below 3 050 m (10 000 ft) AMSL, except where approved by the competent authority for aircraft types, which for technical or safety reasons, cannot maintain this speed. ATC clearance is not required.


Table 1: ATS AIRSPACE CLASSES - SERVICES PROVIDED AND FLIGHT REQUIREMENTS

Class

Type of flight

Separation provided

Service provided

Speed limitation[1]

Radio communication capability requirement

Continuous two-way

air-ground voice communication required

Subject to an ATC clearance

A[4]

IFR only

All aircraft

Air traffic control service

Not applicable

Yes

Yes

Yes

B[4]

IFR

All aircraft

Air traffic control service

Not applicable

Yes

Yes

Yes

VFR

All aircraft

Air traffic control service

Not applicable

Yes

Yes

Yes

C

IFR

IFR from IFR

IFR from VFR

Air traffic control service

Not applicable

Yes

Yes

Yes

VFR

VFR from IFR

(1) Air traffic control service for separation from IFR

(2) VFR-VFR traffic information (and traffic avoidance advice on request)

250 kt IAS below 3 050 m (10 000 ft) AMSL

Yes

Yes

Yes

D

IFR

IFR from IFR

Air traffic control service, traffic information about VFR flights (and traffic avoidance advice on request)

250 kt IAS below 3 050 m (10 000 ft) AMSL

Yes

Yes

Yes

VFR

NIL

IFR/VFR and VFR/IFR traffic information (and traffic avoidance advice on request)

250 kt IAS below 3 050 m (10 000 ft) AMSL

Yes

Yes

Yes

E[4]

IFR

IFR from IFR

Air traffic control service and, as far as practical, traffic information about VFR flights

250 kt IAS below 3 050 m (10 000 ft) AMSL

Yes

Yes

Yes

VFR

NIL

Traffic information as far as practical

250 kt IAS below 3 050 m (10 000 ft) AMSL

No[2]

No[2]

No

F[4]

IFR

IFR from IFR as far as practical

Air traffic advisory service;

flight information service if requested

250 kt IAS below 3 050 m (10 000 ft) AMSL

Yes[3]

No[3]

No

VFR

NIL

Flight information service if requested

250 kt IAS below 3 050 m (10 000 ft) AMSL

No[2]

No[2]

No

G

IFR

NIL

Flight information service if requested

250 kt IAS below 3 050 m (10 000 ft) AMSL

Yes

No[2]

No

VFR

NIL

Flight information service if requested

250 kt IAS below 3 050 m (10 000 ft) AMSL

No[2]

No[2]

No

1. When the transition altitude is lower than 3050 m (10000 ft) AMSL, FL100 should be used in lieu of 10000 ft. The competent authority may also exclude aircraft types which, for technical or safety reasons, cannot maintain speed.

2. Pilots shall maintain continuous air-ground voice communication watch and establish two-way communication, as necessary, on the appropriate communication channel in RMZ.

3. Air-ground voice communication is mandatory for flights participating in the advisory service. Pilots shall maintain continuous air-ground voice communication watch and establish two-way communication, as necessary, on the appropriate communication channel in RMZ.

4. Classes A, B, E and F are not used in the Riga FIR.


Figure - ATS airspace classification

   ENR 1.4.2 ATS AIRSPACE DESCRIPTION

NIL