Narrative:

Upon initial climb out from msp runway 30L; we had lost LNAV/VNAV capability along with loss of some MCP panel function. This was noticed out of 3000 ft AGL as VNAV engagement was attempted. VNAV would not engage. I believe the first officer also noted that the climb page information from his CDU had dropped out. The flight directors both disappeared from view as did the magenta active course line from both navigation map displays. Also; our speed limit markers on the pfd's disappeared. Autopilot would not engage except in control wheel steering (cws) pitch and roll. This all occurred as we were on an assigned heading of 260 from ATC while in heading sel mode. Shortly thereafter ATC gave us direct to a fix on the schep 9 departure; but since we had lost LNAV capability and our route went inactive; we requested a radar vector. ATC was advised of our situation and kept us on a heading while we were running the QRH and trying to troubleshoot the problem. At no time did we ever get any failure flags or get any messages on the CDU's; relating to our problem. We leveled off at an ATC assigned altitude where I again attempted to engage the a autopilot. I was able to use the autopilot in heading select and vertical speed/altitude hold modes. We also had conventional navigation capability. We knew that the destination weather was deteriorating with snow and gusty winds. The visibility was forecast to go to 3/4 of a mile; and ultimately went down to 3/16 of a mile. Continuing on to [destination] did not seem to be a good choice as far as being the safest course of action. Another complication additive to our situation was the fact that our ACARS system was inoperative and on MEL. We ultimately got a patch to dispatch via arinc. At first our communication was difficult due to poor reception; but it got better. I advised dispatch of our situation. I explained I was concerned about the weather and our current navigation situation with reduced capability. Since [destination] was still about one and a half hours away; and had rapidly deteriorating weather; it was agreed that the safest course of action was to divert. Additionally; there was concern on my part about getting up to altitude (planned for FL400) and not having rvsm capability. This could have greatly affected our fuel burn which could complicate the situation further; especially with our ACARS system down. After our dispatcher and the sod had conferred; we all agreed that [the alternate airport] would be a good choice for our diversion. The weather in [there] was good. We had plenty of fuel to make [it]. Since we did not have an emergency and the aircraft was flying safely; we felt that this was a prudent operational decision made with safety as the guiding principle. Shortly after this decision was made; we got a turn towards [alternate]. We requested the [conventional navigation STAR] arrival so that we did not have to comply with any RNAV requirements.as we turned to the southeast our LNAV/VNAV capability returned after being out 10-15 minutes. I advised dispatch of our regained status; but we all felt that a diversion was still the safest course of action with all things considered. We also continued to monitor raw data navigation information so as to crosscheck our position awareness. I then briefed the flight attendants of our plan as we had earlier mentioned to them our status. Also; the passengers were advised that we were going to divert because of diminished navigational capability and poor weather in [destination]; as a safety precaution. We continued on and landed without further incident.

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Original NASA ASRS Text

Title: B737 Flight Crew reported automation problems after takeoff.

Narrative: Upon initial climb out from MSP Runway 30L; we had lost LNAV/VNAV capability along with loss of some MCP panel function. This was noticed out of 3000 ft AGL as VNAV engagement was attempted. VNAV would not engage. I believe the First Officer also noted that the climb page information from his CDU had dropped out. The flight directors both disappeared from view as did the magenta active course line from both navigation map displays. Also; our speed limit markers on the PFD's disappeared. Autopilot would not engage except in control wheel steering (CWS) pitch and roll. This all occurred as we were on an assigned heading of 260 from ATC while in HDG SEL mode. Shortly thereafter ATC gave us direct to a fix on the SCHEP 9 Departure; but since we had lost LNAV capability and our route went inactive; we requested a radar vector. ATC was advised of our situation and kept us on a heading while we were running the QRH and trying to troubleshoot the problem. At no time did we ever get any failure flags or get any messages on the CDU's; relating to our problem. We leveled off at an ATC assigned altitude where I again attempted to engage the A autopilot. I was able to use the autopilot in heading select and vertical speed/altitude hold modes. We also had conventional navigation capability. We knew that the destination weather was deteriorating with snow and gusty winds. The visibility was forecast to go to 3/4 of a mile; and ultimately went down to 3/16 of a mile. Continuing on to [destination] did not seem to be a good choice as far as being the safest course of action. Another complication additive to our situation was the fact that our ACARS system was inoperative and on MEL. We ultimately got a patch to dispatch via ARINC. At first our communication was difficult due to poor reception; but it got better. I advised dispatch of our situation. I explained I was concerned about the weather and our current navigation situation with reduced capability. Since [destination] was still about one and a half hours away; and had rapidly deteriorating weather; it was agreed that the safest course of action was to divert. Additionally; there was concern on my part about getting up to altitude (planned for FL400) and not having RVSM capability. This could have greatly affected our fuel burn which could complicate the situation further; especially with our ACARS system down. After our dispatcher and the SOD had conferred; we all agreed that [the alternate airport] would be a good choice for our diversion. The weather in [there] was good. We had plenty of fuel to make [it]. Since we did not have an emergency and the aircraft was flying safely; we felt that this was a prudent operational decision made with safety as the guiding principle. Shortly after this decision was made; we got a turn towards [alternate]. We requested the [conventional navigation STAR] arrival so that we did not have to comply with any RNAV requirements.As we turned to the southeast our LNAV/VNAV capability returned after being out 10-15 minutes. I advised dispatch of our regained status; but we all felt that a diversion was still the safest course of action with all things considered. We also continued to monitor raw data NAV information so as to crosscheck our position awareness. I then briefed the flight attendants of our plan as we had earlier mentioned to them our status. Also; the passengers were advised that we were going to divert because of diminished navigational capability and poor weather in [destination]; as a safety precaution. We continued on and landed without further incident.

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.