B737-800
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 354
Troubleshooting; Workload; Confusion; Human-Machine Interface
Aircraft Equipment Problem Critical
Air Traffic Control Issued New Clearance; Aircraft Automation Overrode Flight Crew; Flight Crew FLC complied w / Automation / Advisory; Flight Crew Took Evasive Action; Flight Crew Requested ATC Assistance / Clarification; General Maintenance Action
Aircraft; Airspace Structure; Procedure
At FL360; right IRS Fault light illuminated with autopilot disconnected. Speed Trim Failure light also illuminated. First Officer (FO) altitude instruments blank and no FO Flight Display (FD). We ran checklist for IRS Fault and Speed Trim Fail. Unable to restore FO instruments with NAV selected on IRS. ATC was notified of failure along with Dispatch. Flight controls transferred to Captain with good instruments. Checklist completed; IRS switch both on 1. Flight Operations Manual referenced; as autopilot would not engage with either A or B; aircraft not RVSM capable. ATC notified.Vectors and descent provided. Dispatch sends message LNAV/VNAV still operable (via flight director). Captain and FO concur. No instructions on QRH or Dispatch to land at nearest suitable airport so flight continued planned route. CRM and risk management discussed relating to Pilot Monitoring functions for radio; assertive calls for Pilot Flying deviations; and autopilot FD control. Flight continued with Captain manually flying. Arrival; approach and landing were uneventful. Logbook entries made; Maintenance notified via radio.
A B737-800 Captain reported the right IRS Fault Light illuminated accompanied by the autopilot disconnect; SPEED TRIM FAIL and blank First Officer Instruments. The flight descended out of RVSM with an unusable autopilot but continued to the filed destination.