Narrative:

At FL330 normal cruise flight. IMC from approximately 7;000 feet. At somewhere above 14;000 feet; pilot monitoring (pm) noticed icing on the windshield wiper. Engine and wind anti-ice was put on and left on.at FL330; normal cruise at approximately .76 indicated mach number; pilot flying (PF) complained the auto throttle and autopilot clicked off. PF tried reengaging both systems on both autopilots but could not keep either engaged. PF asked pm to check circuit breakers (circuit breaker). All cbs were in their normal position. Pm said he would look at the QRH; but as suspected; no such items were in the QRH index. When pm looked up from QRH; pm said 'airspeed'. Then again; 'airspeed is 220'. The PF looked at the pm's gages and noticed a 50 kt difference (220 kts on pm side; 270 kts on PF side). Then almost simultaneously; both PF and pm said they smelled an acrid odor (like burnt electrical wiring). At this point we donned oxygen (O2); (O2 was left on from the moment we had the odor to after we landed and stopped the aircraft at the gate) identified as an emergency; and started down and started a divert to ZZZ. Soon after descent; confirmation was when the flight attendants called and smelled the same. The smell permeated the entire cockpit and cabin (cockpit crew and cabin did not see any smoke at any time - just the odor which lasted well after we landed and debarked the aircraft) the descent; the PF said the airspeed indicators matched. We had a normal flaps 40 landing and it was VMC conditions light to moderate rain. Aircraft rescue and fire fighting (arff) followed us in and the emergency was complete. Arff walked around the aircraft with the first office (first officer) and did not see anything unusual. First officer looked at the pitot static system items and did not see anything unusual. Also; on descent pm scrolled through all the pitot/static gages and all had power going to each system.

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Original NASA ASRS Text

Title: MD-80 First Officer reported that the Captain and First Officer's airspeed indicators did not agree. Autopilot and auto-throttles tripped off.

Narrative: At FL330 normal cruise flight. IMC from approximately 7;000 feet. At somewhere above 14;000 feet; Pilot monitoring (PM) noticed icing on the windshield wiper. Engine and Wind Anti-Ice was put on and left on.At FL330; normal cruise at approximately .76 indicated Mach number; Pilot Flying (PF) complained the auto throttle and autopilot clicked off. PF tried reengaging both systems on both autopilots but could not keep either engaged. PF asked PM to check Circuit Breakers (CB). All CBs were in their normal position. PM said he would look at the QRH; but as suspected; no such items were in the QRH index. When PM looked up from QRH; PM said 'AIRSPEED'. Then Again; 'AIRSPEED is 220'. The PF looked at the PM's gages and noticed a 50 kt difference (220 kts on PM side; 270 kts on PF side). Then almost simultaneously; both PF and PM said they smelled an acrid odor (like burnt electrical wiring). At this point we donned Oxygen (O2); (O2 was left on from the moment we had the odor to after we landed and stopped the aircraft at the gate) identified as an emergency; and started down and started a divert to ZZZ. Soon after descent; confirmation was when the Flight Attendants called and smelled the same. The smell permeated the entire cockpit and cabin (cockpit crew and cabin did not see any smoke at any time - just the odor which lasted well after we landed and debarked the aircraft) the descent; the PF said the airspeed indicators matched. We had a normal Flaps 40 landing and it was VMC conditions light to moderate rain. Aircraft Rescue and Fire Fighting (ARFF) followed us in and the emergency was complete. ARFF walked around the aircraft with the First Office (FO) and did not see anything unusual. FO looked at the pitot static system items and did not see anything unusual. Also; on descent PM scrolled through all the pitot/static gages and all had power going to each system.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.