What happened
On December 20, 2015, an Embraer ERJ 190-100 LR, registration HB-JVM, operated by Helvetic Airways, was conducting a scheduled passenger flight from London City (EGLC) to Zurich (LS/LSZH). While cruising at flight level 330, approximately 30 NM east-southeast of Reims, the flight crew noticed an unidentified odor within the cockpit. Although the engine indicating and crew alerting system (EICAS) did not trigger any warnings, a cabin crew member subsequently reported a strong electrical smell throughout the cabin.
Following the procedures outlined in the Quick Reference Handbook (QRH) for smoke, fire, or fumes, the crew deactivated the recirculation fans. This action successfully eliminated the odor in the cockpit and the galleys, though the smell persisted in the passenger rows near the wing emergency exits (rows 14 and 15).
After evaluating the situation, the crew decided to continue to Zurich rather than diverting to Basel-Mulhouse, as Zurich was reachable within 120 NM. As a precaution, the crew donned oxygen masks. During the descent, the co-pilot experienced fogging of his mask, which hindered his ability to control the aircraft, leading him to transfer the pilot flying duties to the captain. The crew issued a PAN PAN urgency message to Reims Control and requested a priority landing. The aircraft landed safely in Zurich, where emergency services inspected the cabin, cargo holds, and center bay, but found no evidence of fire or smoke.
The investigation
The investigation focused on identifying the source of the electrical odor. Investigators tested the co-pilot's oxygen mask, which was found to be fully functional. The aircraft's pressurization and air conditioning systems were reviewed, and no recorded errors were found.
To further inspect the cabin, the passenger service units above rows 13, 14, and 15 were opened and examined. Additionally, the air conditioning packs were tested using bleed air from both engines and the auxiliary power unit (APEX) at both minimum and maximum power settings. During these tests, galley equipment, including ovens and coffee makers, were also operated. No abnormal odors were detected during these procedures.