EUROCAE ED-238 PDF

SCOPE AND BACKGROUND

Today, manned aviation safety is ensured by application of regulations concerning materials, procedures and flight rules derived from.

One of the most fundamental capabilities is the “See and Avoid” capability. The pilot of an aircraft is required to be able to see other aircraft and avoid collision, whatever the airspace and environment he/she is flying through. For flight outside controlled airspace, visual acquisition may be the only means available to detect potential conflicting traffic, to achieve safe separation and to avoid collision.

This See and Avoid capability is expected to be replicated in RPAS where the pilot is remote.

ICAO RPAS Manual Doc 10019 [Ref 3] and ICAO Rules of the Air amendment 43 [Ref 2] define Detect and Avoid as, ‘the capability to see, sense or detect conflicting traffic or other hazards and take the appropriate action’, Depending on the type and location of the operations the RPA will conduct, Detect and Avoid would include the ability to:

1. recognize and understand aerodrome signs, markings and lighting;

2. recognize visual signals (e.g. interception);

3. identify and avoid terrain;

4. identify and avoid severe weather;

5. maintain applicable distance from cloud;

6. provide “visual” separation from other aircraft or vehicles; and

7. avoid collisions.

With such a wide range of differing requirements, it is likely that numerous different systems and sensors will be required to collect process and display information to the remote pilot and, where appropriate, automatically initiate RPA manoeuvres or other actions based upon the information received

NOTE: There are alternative definitions of Detect and Avoid in use outside of ICAO.

This OSED is addressing the collision avoidance capability, during en-route operation under Instrument Flight Rules (IFR) in Class A, B and C airspace. This capability is defined as Traffic Awareness And Collision Avoidance and includes

- The provision of traffic situation awareness information to the remote pilot

- The provision of collision avoidance manoeuvre guidance to the remote pilot in the event that a collision risk is detected

- The initiation of an automatic collision avoidance manoeuvre in the event that the remote pilot does not respond to a proposed collision avoidance manoeuvre (for whatever reason) in an appropriate time

- Full traffic awareness and collision avoidance operation, in situations when due to exceptional, circumstances, the Remotely Piloted Aircraft (RPA) is operating in airspace where non cooperative VFR traffic is present, however it does not provide specific guidance for ‘traffic avoidance’(rules of the air separation).

Self-separation and Traffic avoidance functions are out of scope as these are not allowed in Class A, B or C Airspace in which an aircraft may not manoeuvre without an ATC clearance except in an emergency (such as the need to avoid a collision) or to avoid hazardous weather.

The restriction to Class A, B and C arises because it is assumed that the RPA is receiving a separation service, which negates the need for a self-separation function. Apart from this restriction, the document describes a system potentially able to meet the requirements of certain classes of operations for the longer term. It is not intended that anything written here precludes the use of systems with more limited capability should such systems be approved by the appropriate regulators. The guidance in this document may apply to such systems provided it is interpreted appropriately in the light of their limitations. For example, a collision avoidance function with no ability to track non-cooperative traffic might prove acceptable in certain airspace environments.