B737 Next Generation Undifferentiated
Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Flight Crew Last 90 Days 274
Deviation - Speed All Types; Deviation / Discrepancy - Procedural Published Material / Policy
Flight Crew Became Reoriented; Flight Crew Returned To Clearance
Aircraft; Airport; Procedure
Flaps 25 takeoff caused things to happen quicker than we are used to seeing. Flap retraction altitude and clean-up speeds came fast and caught us off guard. During the flap retraction; the airspeed increased above the 200 knots for under the Class B airspace. The airspeed got to about 230 knots and we got a 'Don't sink' warning. [We] corrected immediately. We were only above that airspeed for a few seconds.
B737NG First Officer reported airspeed and vertical speed issues related to a flaps 25 takeoff.