Air Traffic Control of Concorde over the North Atlantic

Concorde Callsigns

 

Like all aircraft crossing the North Atlantic, Concorde needed a flight plan and to be controlled as it flew. All British Airways aircraft have the callsign “Speedbird”, but with Concorde the normal procedure was for the word “Concorde” to be inserted between the airline callsign and flight number; this drew attention to the fact that the aircraft was a Concorde, and had therefore special requirements. So the callsign for the regular scheduled Concorde Flight BA001 would have been “Speedbird Concorde One”. When entering US airspace the word “Heavy” was added to the callsign, this was to identify the type of aircraft being flown, an example of this is “Speedbird Concorde One, Heavy”

Flight plans

 

Concorde operated on three specific Concorde only ‘tracks’ across the North Atlantic Ocean, these tracks formed part of the North Atlantic Track system, but unlike the other NAT (North Atlantic Track) routes used daily by normal airlines which change twice daily to take account of the weather that day, they are fixed in position. This is because during supersonic cruise Concorde flies between 55000ft and 60000ft which means Concorde flies above the weather on the edge of space. These Concorde tracks used the shortest distance possible that kept Concorde away from land and any other air traffic. The three North Atlantic Routes used for Concorde were as below…

 

NAT SM (Sierra Mike) – Normally used for Westbound Concordes flights
NAT SN (Sierra November) – Normally used for Eastbound Concordes flights
NAT SO (Sierra Oscar) – Alternative overflow flight route

The three North Atlantic Routes used for Concorde

Unlike traditional the passenger airliner flights which have a fixed cruise level that have also have sometimes “steps up” at various points during the flights, Concorde was able to use its exclusive airspace to make a more efficient gradual cruise-climb, which typically began at around FL500 (50,000FT) at this point Concorde would only climb slowly as the fuel was burned-up. Concorde had a maximum operating height of FL600 (60,000ft), although it was unusual for Concorde to get this altitude before it was time to begin its descent

The waypoints on each track

(See the picture above)

 

NAT-SM (Westbound
SM15W (50.41N 15.00W)  SM20W (50.50N 20.00W) , SM30W (50.30N 30.00W)
SM40W (49.16N 40.00W) SM50W (47.03N 50.00W) , SM53W (46.10N 53.00W)
SM60W (44.14N 60.00W)  SM65W (42.46N 65.00W) , SM67W (42.00N 67.00W)

 

NAT-SN (Eastbound
SN67W (40.25N 67.00W) SN65W (41.40N 65.00W) SN60W (43.07N 60.00W)
SN52W (45.10N 52.30W) SN50W (45.54N 50.00W) SN40W (48.10N 40.00W)
SN30W (49.26N 30.00W) SN20W (49.49N 20.00W) SN15W (49.41N 15.00W)

 

NAT-SO (Alternate)
SO15W (48.40N 15.00W)  SO20W (48.48N 20.00W) SO30W (48.22N 30.00W)
SO40W (47.04N 40.00W)  SO50W (44.45N 50.00W)  SO52W (44.10N 52.00W)
SO60W (42.00N 60.00W)

 

 

Westbound flights used NAT-SM, Eastbounds NAT-SN and NAT-SO could be used either way

Oceanic Control Procedures

 

All the air traffic control (ATC) was provided via position reporting only. Concordes had to make position reports just like any other aircraft would have, passing each of the SM/SN/SO waypoints. Travelling at Mach 2 Position Reports will be at 15-20 minute intervals. While Concordes were travelling supersonic they had to have a 50 mile horizontal separation from any other Concordes at the same altitude. Although normally there would have only been a maximum of two Concorde crossing the North Atlantic at anytime, one eastbound and the other westbound

 

Concorde Tracks for OCMS

 

NAT-SM – SM15W SM20W SM30W SM40W SM50W SM53W SM60W SM65W SM67W

NAT-SN - SN67W SN65W SN60W SN52W SN50W SN40W SN30W SN20W SN15W

NAT-SO - SO15W SO20W SO30W SO40W SO50W SO52W SO60W