B737-800
Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument
Flight Crew Last 90 Days 280
Confusion; Human-Machine Interface
Aircraft Equipment Problem Less Severe; Deviation - Altitude Overshoot
Flight Crew Overcame Equipment Problem
Aircraft
After departing Runway XX from ZZZ; we received an unexpected increase in airspeed with the nose set to approximately 12 degrees pitch up. At 1;000 feet; I had the PM (Pilot Monitoring) set speed; flaps 5; climb thrust. When the PM went to select the airspeed in the MCP; the window remained closed. As we started to accelerate we begin to retract the flaps on schedule. Trying to reduce the workload in the flight deck; I tried engaging the autopilot. Shortly after engaging the autopilot; we received the Autopilot Disconnect warning. Unable to accelerate above V-MASS I disconnected the autothrottle and let the aircraft accelerate to 210 knots.During that time we received erroneous airspeed and altitude indications. This continued until passing 18;000 feet when the MCP started to operate normally. During cruise; the airspeed remained constant. During our descent into ZZZ1 we felt the best way to control the airspeed was to request the RNAV XXR Approach. We thought the approach would give us a way to control the airspeed. Everything seemed normal until the FAF; when we started to configure for landing. Shortly after configuring; our Airspeed bug was increased to 304 knots with no inputs from the flight deck. When that happened; the Nnav increased our descent rate to keep us on the path. Shortly after that happened we picked up the airport and landed visually. After landing we found that the problem had been written up one day prior. We made the appropriate entries in the Maintenance log. Erroneous airspeed and altitude indications.
Our takeoff was ZZZ Runway XX; with a crosswind of 20 knots. On climbout; around 500 feet AGL; both Pilots saw a 30 knot jump in airspeed and quickly back to normal. No headwind component. At 1;000 feet 'set speed' call; I could not set speed past 170 in IAS/Mach window and it froze at 170 knots. The flight director was directing a climb due to that. I cancelled the autothrottles as they appeared to start reducing power. Autopilot was difficult to engage but eventually engaged; and VNAV closed the airspeed window but the aircraft was not accelerating to 250. Autopilot kicked off when the aircraft tried to level off at 4;000 feet. The aircraft overshot 4;000 feet slightly as autopilot kicking off surprised us. The only way to set airspeed was to set it in FMC; push the VNAV button to close airspeed window; unselect VNAV; and the new airspeed would be set in window but frozen at that speed. En route it was ok as everything seemed to work above FL180. I briefed a plan to use VNAV on arrival as the seemed best instead of setting speeds on configure arriving ZZZ1. On arrival to ZZZ1; weather ended up being 6;000 feet OVC (overcast); 2.5 in rain. Briefed a good plan; FO (First Officer) flew; Captain manipulated speeds and monitored instruments; it was all good until gear down; flaps 15. Autopilot then kicked off speed in FMC and went to 305 knots along with A/S carrots. FO hand flew GPS approach; picked the visual at 2.5 miles; all lined up and landed XXR.
B737-800 flight crew reported erroneous airspeed indication and altitude overshoot on climbout.