ATS 3.3 HARMONISATION OF THE AIRSPACE CLASSIFICATION

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ATS 3.3 HARMONISATION OF THE AIRSPACE CLASSIFICATION

In 1991 in an attempt to harmonise the categories of airspace, ICAO re-classified the airspace offering seven different types. Since then, no review has taken place with regard to whether this re-classification has created a harmonised situation. There is now evidence to suggest, that there is a lack of harmonisation between neighbouring countries, and that there exists a degree of under and over classification.

Class E Airspace is the lowest class of controlled airspace. Controlled doesn’t mean visual flight rules (VFR) traffic have to be in radio contact with air traffic control (ATC), but that ATC services are available within the capabilities of radar and radio equipment. Instrument flight rules (IFR) traffic is required to contact ATC for a clearance. This is general-purpose airspace and aircraft flying under VFR can fly more-or-less wherever they want (weather permitting) and IFR traffic operates under positive control by ATC. There are regulations in this airspace but they aren’t onerous, and they’re designed to accommodate the variety of aircraft and activities that can be found here. Although Class E airspace is a single class of airspace, there are tighter regulations above 10,000 feet, where there are no airspeed restrictions (other than the prohibition on supersonic flight over land) compared to lower altitudes where airspeeds are limited to 250 knots.

The current ICAO airspace classification scheme was adopted in 1990, consisting of seven classes of airspace, each specifying minimum ATS requirements and the services provided.

No concrete evidence could be found to suggest that there is a lack of harmonisation between neighbouring countries or that there is a degree of over and under classification.

IFATCA policy is incorrect stating that Class E airspace is uncontrolled, it is controlled airspace for IFR traffic and uncontrolled for VFR. ATC services are provided to IFR flights, while traffic information is provided to VFRs.

The ICAO rules pertaining to Class E airspace are clear. As long as ATCO’s comply with these rules the liabilities and responsibilities for separation between IFR and VFR traffic should fall to the pilot in VMC. ATCO’s are not encouraged to give radar headings to IFR traffic to avoid VFR traffic but rather give traffic information, as there might be other VFR traffic in the area that is not known to the ATCO.

Class E airspace is the highest risk airspace of all the controlled airspaces and was intended that way with the ICAO airspace classification system; this is to give more freedom to the users of Class E airspace.

There is a weather minima chart to try and mitigate the risk of IFR and VFR traffic sharing Class E airspace.

It is practically impossible to determine the legal implications in the event of an incident or accident that occurred in Class E Airspace on a global platform. States could assess the situation in a different way and expect controllers to perform in a specific way.

Pilots experience difficulties to be constantly aware of the type of airspaces crossed while preparing for an approach and looking outside in compliance with the “see and avoid” rule.

One of the critical safety issues regarding class E airspace is the speed of modern aircraft and the ability of the human eye to detect aircraft in a clear futureless sky.


IFATCA Policy is:

MAs shall urge ATS Authorities to co-ordinate and harmonise with all neighbouring states their national airspace classification, in accordance with ICAO Annex 11 Appendix 4, to permit safe and efficient operating conditions to all airspace users and air traffic controllers. Airspace classification should be appropriate for the traffic operating in the airspace, to avoid over and under classification. As traffic situations change, the classification may have to change accordingly. Local operational controllers should be involved in the airspace classification process.


See: WP 310 – Las Vegas 2016

 

Last Update: October 2, 2020  

November 4, 2019   429   Jean-Francois Lepage    ATS    

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