B737-800
Flight Crew Air Transport Pilot (ATP)
Aircraft Equipment Problem Critical
Flight Crew Diverted; Flight Crew Executed Go Around / Missed Approach
Aircraft
We were descending on the approach to Runway XY. At about 5 NM from the runway and decelerating for flaps 30; the red low speed barberpole began to rise up to our current airspeed which was 170 KIAS. At the same time the low speed (A)lpha warning indicated on the MCP panel and indicated 135 KIAS. With an unknown airspeed anomaly we elected to abandon the approach and go around. During the go around after flaps were selected to up; we both noticed that the flaps stopped retracting at about 9 degrees. The flap handle was up and the leading edge flap transit amber light was on. All indicators were green on the overhead flaps panel. I [let] ATC [know the situation] and got the QRH out to run the leading edge flaps transit checklist. I notified the flight attendants of our status and the decision to divert to [an airport with a longer runway.] ATC vectored us for an approach to Runway XX. A full stop landing was made uneventfully. The airspeed indications and the barberpole low and high speed warnings indicated normally; and appeared to have been normal after about 5 minutes once we elected to go around.
B737-800 Captain reported airspeed indicator malfunction on approach. A go around was executed; and flaps failed to retract. Flight diverted to a nearby airport with a longer runway.