Widebody; Low Wing; 2 Turbojet Eng
Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Situational Awareness; Time Pressure
Conflict Airborne Conflict; Deviation - Speed All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural FAR
Air Traffic Control Issued New Clearance; Air Traffic Control Separated Traffic; Flight Crew Requested ATC Assistance / Clarification; Flight Crew FLC complied w / Automation / Advisory
Human Factors; Procedure
Our PDC was an RNAV departure. The aircraft in front of us; I assume; was issued same departure initially was then given a left turn to 330 and climb to 5;000 feet due to traffic. Once in position we were given amended take-off instructions of turn left heading 330 climb and maintain 5;000 feet. We complied and switched to Departure Control. At 2;200 feet Departure Control gave us clearance to climb to 16;000 feet. Climbing through 4;000 feet; we were then told to level off at 5;000 feet. During the level off; Aircraft Y came into view at 12 o'clock and about 3 miles. He was in what appeared to be a 180 degree right turn towards north. Simultaneously; we got a TA (Traffic Advisory) followed a few seconds later by an RA (Resolution Advisory) of 'Level off; Level off.' The Pilot Flying followed procedures and disconnected autothrottles; autopilot was not yet engaged. The clearance altitude of 5;000 feet was not exceeded. During the RA event; ATC gave us a left turn to 270 degrees. The Pilot Flying asked to be automated. Airspeed increased to approximately 273 kts for about 5 seconds during the RA and level-off event. Our speed was then reduced to 250 kts. Speed limit exceeded populated in the FMS scratch pad. No airframe limitations were exceeded.The simple cause of the airspeed exceedance was too much power in the level-off. However; the late amended clearance level-off instructions; turbulence; the TA and subsequent RA; [and] the Pilot Monitoring being distracted by the traffic threat while manipulating the radios; were the indirect and main causes of the excess airspeed. The RA; in my opinion; was due to [the] lack of information shared by the Departure Controller. We were not given the reason for the amended clearance and level-off. If we would have known that we were climbing into traffic; we would have decreased the climb rate. The simple cause of the airspeed exceedance was too much power in the level-off. However; the late amended clearance level-off instructions; turbulence; the TA and subsequent RA; [and] the Pilot Monitoring being distracted by the traffic threat while manipulating the auto pilot and radios; were the indirect and main causes of the excess airspeed. It sounded like the Controller was distracted or overwhelmed and should have shared more info or given us a more westerly turn on departure; i.e. heading 270 instead of 330. Autothrottles remained on.
Air carrier Captain reported that as Departure Control issued an instruction to level off at a lower altitude than initially assigned; received a TCAS RA for a VFR aircraft in their path.