Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 245
Confusion
Deviation - Speed All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Flight Deck / Cabin / Aircraft Event Other / Unknown
Flight Crew Became Reoriented; Flight Crew FLC complied w / Automation / Advisory
Human Factors
On takeoff from 13R; the F/O (First Officer) was flying and commanded 'Gear Up'. Without recognition of my actions; as I was Pilot Monitoring; his first takeoff of our trip; I put the flap lever from Flaps 1 to Flaps Up. Immediately after this action; the F/O commanded LNAV as he had missed engaging it during his departure brief; and I missed it during my pre-departure cleanup of the MCP (Mode Control Panel). As I selected LNAV for him we got an 'Airspeed Low' aural warning. I immediately looked at the airspeed indicator and saw 155 with a yellow box around it. I told the F/O; Pilot Flying our airspeed was low and to accelerate; but did not recognize my error until we reached 1000 feet AGL and I went to put the flaps up. It was then I recognized the flaps were up and the gear was down. I raised the gear; the aircraft accelerated and the rest of the flight was uneventful.
B737 Captain reported inadvertently raising the flaps instead of the gear after takeoff.