B737-700
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 46
Troubleshooting
Aircraft Equipment Problem Less Severe; Deviation - Altitude Excursion From Assigned Altitude; Deviation - Speed All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter Weather / Turbulence
Flight Crew FLC Overrode Automation; Flight Crew Overcame Equipment Problem
Aircraft; Weather
As Pilot Flying; we were navigating around moderate to heavy precipitation using heading select and climbing to FL330 using VNAV. During the climb; I realized I had bad air data; as the airspeed suddenly displayed in the 130 knot range along with other erroneous readouts. At the same time I was trying to diagnose the situation; the Captain noticed the autopilot had commanded a descent. Realizing my computer was receiving bad data; controls were quickly transferred to the Captain; who turned off the automation and began to hand fly. In regaining positive aircraft control; our flight altitude reached 33;100 ft; but simultaneously we were also given a new heading and altitude clearance of FL390. The autopilot was commanded back on and the flight continued a normal climb using the Captain-side air data. During the climb; we discussed the situation and determined the First Officer static port had iced over and caused my computer to display wrong information. The system returned to normal once clear of the precipitation; and the aircraft control was later returned to the First Officer side after verifying read outs on both sides corresponded with each other.
[Report narrative contained no additional information.]
B737 flight crew reported that the First Officer experienced erroneous airspeed indications while flying through heavy rain.