B737-900
Flight Crew Air Transport Pilot (ATP)
Situational Awareness; Confusion
Aircraft Equipment Problem Critical; Deviation - Altitude Excursion From Assigned Altitude; Deviation - Altitude Overshoot
Air Traffic Control Provided Assistance; Flight Crew Landed in Emergency Condition; Flight Crew Requested ATC Assistance / Clarification
Aircraft
Enroute we climbed from FL350 to FL370. This was done in VNAV. At about FL365 the First Officer's (FO) airspeed clacker started sounding and indicated an over speed. VNAV reverted to control wheel pitch. The FO was the pilot flying. My airspeed indicator (the Captain and pilot monitoring) was showing that we were getting slow and after referencing the standby airspeed indicator we were able to determine that the Captain's airspeed was accurate. We transferred control of airplane to me; I disengaged the auto throttle and auto pilot and added power as well as started a descent to regain speed and proper assigned altitude.Because the first officer's airspeed and altitude indicator were erroneous and indicating the wrong altitude; we had ascended approximately 300 feet past our assigned altitude. This was corrected with the transfer of control.We [advised ATC] and requested a lower altitude as well. The AIS disagree light and the ALT disagree light illuminated on PFD. Also the engine #1 and #2 ECC ALTN lights illuminated along with the associated master caution ENG light.We ran the QRC for airspeed unreliable and the QRH checklist; then ran the ECC ALTN checklist. We descended to FL330 to have a larger airspeed window to operate in. Using the charts in the QRH; we calculated pitch and power settings for various aircraft configurations and to further cross check the Captain's instruments were reading correctly. We consulted Dispatch and Maintenance. Considering all the information we had; including weather and arrival runways; we elected to continue to the destination. Also we changed the transponder to number one so ATC could see our correct altitude. Descent was made to FL280 to exit RVSM airspace.I briefed the flight attendants and passengers of our situation.We maintained our emergency status for the remainder of the flight as a precaution. The First Officer's airspeed indicator read as low as 45 knots on the descent and altimeter was off as high as 800 feet. On approach his airspeed and altimeter were still off but back in the + or - 10 knot range.We requested and received a long straight in final. Landing was normal. ATC from center to tower was very helpful. I'm sure they had to expend extra effort to accommodate our requests. I'm grateful for their efforts.At the gate I called dispatch; maintenance control; and Ops to debrief. Also we debriefed the flight attendants as well. The cause was a pitot static system failure.
B737 crew reported a failure of the First Officer's pitot-static system which affected the airspeed and altitude indications.