B777-200
Human-Machine Interface; Communication Breakdown; Situational Awareness
Conflict Airborne Conflict; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Issued Advisory / Alert; Flight Crew FLC complied w / Automation / Advisory
Aircraft; Airspace Structure; Procedure
We were cleared to climb from FL200 to FL210. There was traffic above us diverging across our flight path. We started the climb in VNAV which was about 2500 FPM. Approximately at FL205 we received a 'Traffic; traffic' TA. We were in VMC and had the traffic in sight; but did not take any action at this point. Approximately FL207 we received the RA 'Level Off.' We were in VNAV ALT at that time; capturing FL210. The level off while using autopilot satisfied the RA 'do not fly' red box and was allowed to continue to complete the level off which was already in progress. The conflicting traffic passed above and slightly behind us and they reported to ATC that they had us in sight. ATC then reported to us they received a notice from our TCAS regarding the RA and asked us verbally to confirm the extent of the RA. Climbing a very light aircraft in VNAV resulted in a high rate of climb. Knowing that there was conflicting traffic above us we should have initiated a slower rate of climb using VERT Speed especially after receiving the TA. This may have precluded this RA.
ATC issued a B777 clearance from FL200 to FL210 with opposite direction traffic and the TCAS RA alerted as the aircraft leveled with VNAV engaged; quieting the alert.