B737 captain reported during climb to FL250 aircraft began to experience multiple air data systems f...

Narrative:

Climbing through approximate FL250 in IMC and icing conditions; we got an IAS disagree alert on the pfds. We noticed a difference between the captain's and first officer's airspeed indicators. Shortly after; we got an altitude disagree alert as well. We realized the captain's instruments and the stby information were correct. While we ran the airspeed unreliable checklist we coordinated with ATC for a block altitude of FL320-340 and a vector to the west to avoid the weather in the northeast. At FL320 the captain's and the stby airspeed indicators were about 290 knots and the first officer's was 150 knots; and the altimeters differed by about 800 feet. We also had an engine annunciation for the eecs in altn mode and completed that checklist as well. We informed dispatch and coordinated a divert to ZZZ1. We [spoke] with ATC but required no further assistance. We completed the overweight landing checklist--we would be landing just under 160;000 lbs. Descending through about 16;000 feet on arrival the first officer's instruments returned to normal. We completed an uneventful approach and landing and taxied to the gate.

Original NASA ASRS Text

Title: B737 Captain reported during climb to FL250 aircraft began to experience multiple Air Data Systems failures; compelling Flight Crew to divert to make a precautionary landing.

Narrative: Climbing through approximate FL250 in IMC and icing conditions; we got an IAS Disagree alert on the PFDs. We noticed a difference between the Captain's and First Officer's airspeed indicators. Shortly after; we got an ALT Disagree alert as well. We realized the Captain's instruments and the STBY information were correct. While we ran the Airspeed Unreliable checklist we coordinated with ATC for a block altitude of FL320-340 and a vector to the west to avoid the weather in the northeast. At FL320 the Captain's and the STBY airspeed indicators were about 290 knots and the First Officer's was 150 knots; and the altimeters differed by about 800 feet. We also had an ENG annunciation for the EECs in ALTN mode and completed that checklist as well. We informed Dispatch and coordinated a divert to ZZZ1. We [spoke] with ATC but required no further assistance. We completed the Overweight Landing checklist--we would be landing just under 160;000 lbs. Descending through about 16;000 feet on arrival the First Officer's instruments returned to normal. We completed an uneventful approach and landing and taxied to the gate.

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.

Attributes
ACN	1667756
Time
Date	201907
Local Time Of Day	0001-0600
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	IMC
Light	Night
Aircraft 1
Make Model Name	B737-800
Operating Under FAR Part	Part 121
Flight Phase	Climb
Flight Plan	IFR
Component
Aircraft Component	Air Data Computer
Person 1
Function	Pilot Not Flying Captain
Qualification	Flight Crew Multiengine Flight Crew Instrument Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	Aircraft Equipment Problem Less Severe Deviation - Procedural Published Material / Policy Inflight Event / Encounter Weather / Turbulence

B737 captain reported during climb to FL250 aircraft began to experience multiple air data systems failures; compelling flight crew to divert to make a precautionary landing.