Narrative:

While in the climb out at approximately FL284; the autopilot disengaged while simultaneously the captain's pfd and mfd lost all indications. I transferred control of the aircraft to the first officer (first officer). We stopped the climb and descended out of rvsm. The amber IRS fault light along with the master caution IRS lights had illuminated. I ran the corresponding QRH checklist for the IRS fault. We operated with the IRS selector switch in both on right. I established a radio patch with dispatch and a subsequent conference call with maintenance. We discussed what had happened and the possibility of diverting into [a nearby alternate]. After seeing the taf called for broken clouds I ruled that out. As we progressed to the east we could see [another possible alternate]. After discussing the situation with first officer; we decided that our best course was to divert into [that airport]. With the loss of redundant attitude; airspeed; and altitude indications; the continuation did not seem like the best plan of action and diverted.

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Original NASA ASRS Text

Title: B737 Captain reported diverting to an alternate airport after noting the loss of the L IRS system.

Narrative: While in the climb out at approximately FL284; the autopilot disengaged while simultaneously the Captain's PFD and MFD lost all indications. I transferred control of the aircraft to the First Officer (FO). We stopped the climb and descended out of RVSM. The amber IRS fault light along with the Master Caution IRS lights had illuminated. I ran the corresponding QRH checklist for the IRS fault. We operated with the IRS selector switch in BOTH ON RIGHT. I established a radio patch with Dispatch and a subsequent conference call with Maintenance. We discussed what had happened and the possibility of diverting into [a nearby alternate]. After seeing the TAF called for broken clouds I ruled that out. As we progressed to the east we could see [another possible alternate]. After discussing the situation with FO; we decided that our best course was to divert into [that airport]. With the loss of redundant attitude; airspeed; and altitude indications; the continuation did not seem like the best plan of action and diverted.

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.