Dash 8-100
Flight Crew Air Transport Pilot (ATP)
Workload; Time Pressure
Aircraft Equipment Problem Critical; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor
Flight Crew Landed in Emergency Condition; Flight Crew FLC complied w / Automation / Advisory; Flight Crew Took Evasive Action; General Evacuated
Aircraft
Aircraft emergency for smoke in the cockpit on approach.  On final approach the First Officer noted the odor of matches. A short time later a light smoke appeared on the flight deck. I commanded that I had the aircraft and ordered the First Officer to suit up. I notified the Tower that we were an emergency and requested the fire trucks because we had smoke in the cockpit. I completed the landing checklist from memory. When the First Officer completed suiting up I order him to complete the landing checklist. At this point we were very close to the runway. I landed short; exited on Taxiway Delta. Stopped the aircraft. Shutdown the engines and turned off on electrical power. I then order the evacuation of the aircraft through the main cab door. I proceeded out the main cabin to direct the passengers to the terminal. During the evacuation the First Officer completed the after landing and securing checklist. The Flight Attendant directed the passengers during the evacuation. The truck arrived at the aircraft before we had completed the evacuation. After completing the evacuation I assisted CFR in disconnecting the aircraft batteries.
A matchstick like smell was first noticed on approach. It was initially not strong. A stronger smell became obvious on roughly a 3-6 mile final. Smoke was then visually observable in the cockpit shortly after prompting the decision to [advise we were] an emergency. We confirmed the landing checklist was complete and that we would evacuate after landing. Smoke from unknown source; memory items implemented; Flight Attendant notified; aircraft evacuated after landing. Communications with ATC and the Flight Attendant were extremely difficult using the oxygen mask.
On final approach; a DHC-8-100 cockpit developed a matchstick odor followed by smoke; so oxygen masks were donned; ATC was advised; and after landing the Captain ordered an evacuation. Oxygen mask communications were difficult.