Smoke in the Cockpit at FL370 with Opposite Traffic Below
At 0310Z a B757-200 freighter, 130 nm east of Las Américas (SDQ) at FL370 on a westerly track, transmits: 'Mayday, mayday, mayday, smoke in the cockpit, request immediate descent and diversion to Santo Domingo.' The crew has donned oxygen masks and reports the smoke is increasing. An A330 is at FL350, 60 nm ahead of the B757 on the same airway, eastbound; a B777 is at FL350, 25 nm behind, also westbound. The B757 pilot asks for 'any level, we need down now', states the aircraft is too heavy to hold and does not intend to dump fuel. SDQ is fine: wind 090/06 kt, visibility 10 km, few cloud at 3,000 ft, QNH 1011 hPa, ILS RWY 17 available. The TMA is quiet at this hour, but the tower and RFFS are at reduced night staffing and the airport's only ambulance is off-site on another call. Terrain west of the field rises to 8,000 ft.
1. What is your first transmission, and how do you protect the descent path from the two aircraft at FL350?
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The emergency aircraft has priority, but a descent from FL370 through FL350 cannot be issued until FL350 is clear. Acknowledge first, then move the traffic, then clear the descent - in that order, in one continuous flow.
- 'B757, roger mayday, standby one, descend when I say.' Acknowledge the mayday so the crew knows you have heard it.
- Move the A330: 'A330, turn right heading 250, maintain FL350, traffic an emergency descent, do not descend.' Turning it off the airway gives lateral protection.
- Move the B777: 'B777, turn left heading 270, maintain FL350, emergency traffic ahead descending.'
- Then: 'B757, turn right heading 240, descend unrestricted to FL100, report leaving FL370, SDQ QNH 1011.'
Keep the B757 east of the high ground while it descends; terrain west of the field rises to 8,000 ft, so 'descend unrestricted' must be paired with headings that keep it over water or the coastal plain until it is below the minimum vectoring altitude. Do not hold the descent while you coordinate - coordinate in parallel, or the smoke wins.
2. What information do you need from the crew, and what do you pass, while keeping the frequency usable?
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Ask only what changes your handling: souls on board, fuel endurance in minutes, whether the crew is on oxygen, whether they can fly an ILS, whether the aircraft is depressurised, and whether they intend to land overweight. Ask these in one or two transmissions, not a stream of questions - a crew fighting smoke has little capacity for a checklist of questions from ATC.
Pass: the QNH 1011, the ILS RWY 17 details, distance and heading to the field, the wind, the RFFS category, and the expected landing runway. Offer a straight-in if the geometry allows.
Keep the frequency usable by moving all other traffic to another frequency, using 121.5 only for traffic that needs it, and keeping every transmission to the emergency aircraft short and standard. Do not fill the frequency with your own coordination calls to the tower; use the landline. Silence on the frequency is a service to a crew in smoke, not a gap to be filled with chatter.
3. What coordination and notification follows, and what changes if the crew later reports the fire is out?
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Immediate coordination: the tower, to alert the RFFS and request the maximum category for the aircraft type with a pre-set overweight landing; the airport operator and emergency services, plus whatever ambulance cover the airport can actually produce - one ambulance off-site is a plan you need to know about now, not on touchdown; the supervisor; and the adjacent ACC for the airspace. Warn the rescue coordination centre as well, because the aircraft is 130 nm east of the field over water for part of the descent and a ditching is a possibility until it is on the ground.
Notification afterwards: the operator's duty office, the airport authority, and a written occurrence report feeding the SMS investigation.
If the fire is reported out: the crew may downgrade to urgency and say PAN PAN, but you do not downgrade the response yourself. Keep the priority and the RFFS response; the aircraft is still landing overweight with possible structural or brake damage. Offer a hold to reduce weight if the pilot wants one - that is his decision, not yours. Do not stand down the emergency services until the crew confirms the situation and the aircraft has come to a stop on the runway.