Flight Crew Air Transport Pilot (ATP)
Flight Crew Total 11500; Flight Crew Type 703
Situational Awareness; Human-Machine Interface; Confusion
Deviation - Speed All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Clearance
Air Traffic Control Issued New Clearance; Flight Crew Became Reoriented
Chart Or Publication; Human Factors; Procedure
When climbing out on the ORD2 departure after reaching 10000 ft the 250 knot speed restriction was accidentally exceeded. The restriction was lifted while we were approaching 13000; but we were already not complying with the 250 knot restriction.
Pre-departure briefing included the speed restriction of 250 kts until cleared to accelerate on the ORD2 departure. Nonetheless; the airspeed bug drove the flight directors pitch down to accelerate as we climbed above 10;000 ft. All 3 of us missed that I followed the flight director and accelerated to ECON climb speed of roughly 300 kts without clearance to accelerate. It only occurred to us that we had inadvertently violated the speed limit when ATC said 'resume normal speed'. The rest of the flight was unremarkable.
Air carrier flight crew reported exceeding the speed restriction that limits aircraft to 250 knots until 13;000 feet on the ORD2 SID.