C-GAAT, a Beech 1900D aircraft operated by Exploits Valley Air Services (EVAS), was conducting flight EVS7775 from Halifax/Stanfield Intl, NS (CYHZ) to Fredericton Intl, NB (CYFC) with 2 crew members and 13 passengers on board. While climbing through 5500 feet following the departure from Runway 05 at CYHZ, passengers alerted the flight crew of the presence of smoke in the cabin. The flight crew selected engine bleed air switches off and the smoke began to dissipate. An emergency was declared and vectors were requested for the return to CYHZ, where the ILS to
Runway 14 was conducted. Neither the flight crew nor the passengers donned the available oxygen masks.
Following the landing, the aircraft taxied onto Runway 23 where rescue vehicles were standing by.
The engines were shut down, the first officer exited the aircraft to assist the evacuation of the passengers, and lead them away from the aircraft. A bus was subsequently sent to the location
and the passengers were transported to the terminal.
The operator’s maintenance conducted an inspection on site before the aircraft was towed to the hangar. Both runways at CYHZ were closed by Notam for approximately 30 minutes while the aircraft was removed. Maintenance personnel determined that the Air Cycle Machine (ACM) was the source of the smoke. This determination was confirmed by TSB investigators who deployed to the airport and spoke to both maintenance personnel and the flight crew, as well as conduct an independent inspection of the aircraft. The faulty ACM was replaced with a serviceable unit and
was tested before flight to confirm the fault was rectified. Following the test, the aircraft was returned to service.