Cabin Odour and Headache on a Short Sector
On a 45-minute turboprop sector, the cabin crew report a 'hot oil' smell shortly after top of climb. Cabin altitude is normal at 7,500 ft. Two cabin crew develop headaches and dizziness, and one passenger vomits. There is no dedicated carbon monoxide detector, and the passengers are not on oxygen. The captain feels 'slightly light-headed' but the aircraft is 20 min from the destination, where maintenance is based; the alternate is 12 min away with no maintenance. The first officer also notices the odour on the flight deck. The captain considers continuing because the destination has maintenance and the passengers have connections. The aircraft has a serviceable autopilot and the weather at both airports is fine. The cabin crew are otherwise healthy and none has a history of motion sickness.
1. Assess the likely hazard and decide whether to continue to destination. Distinguish the presentation from hypoxia and motion sickness.
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The cluster of a hot-oil smell, headaches, dizziness and vomiting in cabin crew and a passenger points to a contaminated air supply, such as engine oil or hydraulic fluid fumes, or carbon monoxide, not simple motion sickness. Motion sickness usually builds with turbulence and affects susceptible passengers, but it does not explain the odour or the crew's headache and dizziness. Hypoxia is less likely because the cabin altitude is normal at 7,500 ft, although carbon monoxide can cause headache and dizziness at normal cabin altitude; carbon monoxide has no smell, so the oily odour suggests other irritating fumes. The captain's own light-headedness is a red flag: the flight deck is also affected. Continuing for 20 minutes to a maintenance base is not justified when an alternate is 12 minutes away. The decision should be to don oxygen masks, descend if needed, and land as soon as practicable at the nearest suitable airport. Do not wait for a detector reading; the absence of a detector is not evidence of safety.
2. What crew coordination and communication actions should be taken during the diversion?
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First, both pilots should don oxygen masks and establish a clear plan: 'We are treating this as a fume event; I will fly, you communicate.' The captain should delegate the cabin call: tell the cabin crew to keep passengers calm, use portable oxygen if available, and report any worsening symptoms. ATC should be told 'urgent' or 'Mayday' depending on severity, with the nature of the problem and the intended airport. The first officer should run the relevant checklist and avoid unnecessary electrical or bleed changes that could worsen the situation; follow the operator's smoke and fumes procedure. The crew should not open the flight deck door repeatedly or leave the seats unattended. If anyone becomes confused or the captain's symptoms worsen, the other pilot should take control. After landing, arrange medical evaluation for all affected crew and passengers before anyone drives home or continues duty.
3. What post-flight reporting and just-culture issues arise?
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Report it as a safety occurrence, not as a disciplinary matter. The report should include time, phase of flight, odour description, symptoms, cabin altitude, oxygen used, diversion and maintenance actions. Preserve the aircraft for engineering inspection of filters, bleed air and oil seals, and record the crew's exposure. Under just culture, the flight crew should not be blamed for the contaminant; the focus is on system fixes: detector availability, maintenance checks and clear fume-event procedures. Cabin crew and passengers should be interviewed and followed up, because symptoms can be delayed. If the captain felt pressure to continue to the maintenance base, that is a reporting point about operational pressure, not a personal failing. The operator should feed the event into its safety management system, review whether the aircraft should have been dispatched, and communicate lessons without identifying individuals unnecessarily.