B737-800
Flight Crew Air Transport Pilot (ATP)
Distraction; Situational Awareness; Workload
Deviation - Speed All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor
Flight Crew Became Reoriented; Flight Crew Diverted; Flight Crew Landed in Emergency Condition
Aircraft; Human Factors
I received a 4 chime call from our Number 1 Flight Attendant. In a panicky voice; I was informed that there was fire and smoke in the cabin; and that we need to land immediately. We advised ATC and started our divert. During our descent; My First Officer suggested that we add the drag to help get the descent going as I started to slow through 265 as we were approaching 10000 ft. I thought we were fine. As we continued coordination with ATC; AARF; and Flight Attendants - I then decided that the gear would be a good option. I was hand flying and proceeding directly to the outer marker. I glanced at the airspeed and thought I saw 265 again and called for gear down; My First Officer put gear down as he was saying verified. And then said not verified and immediately put the handle back up. The gear never moved. Just the handle. I was around 285. So either I misread the airspeed and thought I was at 265. Or I was at 265 and pushed the nose over while hand flying and called gear down and airspeed crept up quickly. The correction was so swift that I quickly dismissed it. The rest of divert went well.Nothing I would change as I thought I saw the correct gear speed. If anything; slow a little bit down. Pressed a little [more] than other emergencies due to it was smoke in the cabin and hearing the panic in the flight attendant voice.
B737-800 Captain reported the landing gear lever was moved to the down position at a speed higher than authorized during a rapid descent.