Loss of Separation - ATCO-induced Situations
From SKYbrary Wiki
|Category:||Loss of Separation|
Loss of separation between aircraft sometimes occurs as a result of action taken (or not taken) by the ATCO.
- Loss of separation from other aircraft may result in collision or the need for flight crew to take visual or Airborne Collision Avoidance System (ACAS) avoiding action at close range to avoid one.
- Injury, especially to cabin crew or passengers, may result from any unusual manoeuvres to avoid a collision.
- Injury to the occupants of an aircraft, especially Cabin Crew, may also result from wake vortex turbulence encounter.
- High levels of stress for the pilots and controllers involved, which may lead to reduced performance.
- Standard Operating Procedures, in the ATSU, which detail procedures to be followed to reduce the chance of loss of separation.
- Routine structured scan helps controllers detect potential conflicts well in advance and mitigate the "blind spot" effect.
- Onboard aircraft equipment designed to warn of potential collision with other aircraft (ACAS/TCAS).
- Use of controller support tools, e.g. Tactical Controller Tool (TCT)
- Ground-based equipment designed to warn of potential collision with other aircraft: STCA (STCA).
- Flight clearance does not provide adequate separation from other traffic.
- ATCO does not detect developing potential conflict.
- Avoiding action issued is too late or inadequate to provide safe separation.
- Instruction not received or not understood by intended recipient due to breakdown in air-ground communications.
- The controller issues a clearance that creates a conflict with a neighbouring aircraft due to the blind spot effect.
- Volume of traffic;
- Military traffic operating out of the segregated area in civil airspace
- Flight crews (military or civil) unfamiliar with the applicable rules and procedures in a particular volume of airspace;
- Failure to pass an Instrument Flight Rules (IFR) aircraft timely traffic information about Visual Flight Rules (VFR) aircraft in its vicinity;
- Issue of a VFR clearance in airspace where the only prescribed traffic separation is IFR against IFR when the ability of the VFR aircraft to comply with its clearance and maintain an effective visual lookout may be compromised by weather conditions;
- Poor (or missing) coordination between adjacent sectors or units;
- Transfer on the wrong frequency may result in the inability of both controllers to issue timely instructions or a communication loss.
- Obscured track labels (e.g. due overlapping, filters, colour representation, etc.).
- ATCO Work-Load
- Interruption or Distraction
- Improve standard of ATCO training, especially in:
- Loss of Separation
- Loss of Separation - Pilot-induced Situations
- Accident and Serious Incident Reports: LOS contains a number of examples of ATCO induced loss of separation.
- Minimum Hours in Position
- Conflict Detection with Adjacent Sectors
- Loss of Separation at Sector Boundaries
- Loss of Separation During Weather Avoidance
- Blind Spots – Inefficient conflict detection with closest aircraft
- HindSight1 Analysis of an AIRPROX between a B737 and an A340;
- HindSight2 Loss of Separation - an Incident at Paris/Orly;
- HindSight3 Loss of separation: The Blind Spot;
- HindSight4 Loss of Separation - A Lesson for the Instructor;
- HindSight5 Loss of Separation - TCAS and STCA - Not Just Anagrams
- HindSight6 Loss of Separation - Mid-Air Collisions, Elephants, and Systems Approaches