10. Air-traffic control over the Atlantic

Question 1

Who has responsibility for ATC over the North Atlantic?

Answer 1

Shanwick Oceanic Control Area (based in Prestwick).
This is shared by 
- the UK 
- Portugal, 
- the USA, 
- Canada 
- Iceland

Question 2

How do pilots and ATC communicate?

Answer 2

• Voice comms maintained through HF (High Frequency) radio (based in Shannon in the west of Eire).
• Pilots report position every 10 degrees of longitude.

Question 3

How is the Atlantic controlled?

Answer 3

A system of organised tracks is constructed by the relevant Oceanic Area Control Centre (OACC) every 12 hours.
Prestwick OACC is responsible for the westbound track system (usually through UK airspace between 1000hrs and 1600hrs)
When organising the track structure the prevailing wind is taken into account to take advantage of a tailwind, which is more fuel economical and gets aircrafts to their destinations faster.

Question 4

What information will be included in clearances to cross the ocean?

Answer 4

• The track
• FL
• Speed
• Any time restrictions for entry on to the track structure

Question 5

What is Oceanic Control Tracks and Separation?

Answer 5

There are 5 tracks (A, B, C, D, E)

• 60 NM lateral separation between aircraft at the same level
• 10 minutes longitudinal separation between aircraft at the same level on the same track
• 1,000ft vertical separation in Reduced Vertical Separation Minima (RVSM) airspace above FL290 and FL410, otherwise 2,000ft.

Question 6

How do planners ensure the safe passage of aircraft across the Atlantic?

Answer 6

Planners on either side of the Ocean consult with each other and co-ordinate with adjacent OACCs as well as domestic ATC agencies.

Modern equipment installed at Prestwick ensures that Air Traffic Controllers are able to detect and resolve conflictions on the oceanic track.