Narrative:

Immediately after takeoff, flight mode annunciator displayed a heading error message and a no autoland message with a 30 degree heading split in right and left heading system with central air data computer #2 selected. In the ensuing confusion we discovered that the standby compass mirror in the standby compass housing (located behind and above the first officer) was not properly adjusted. This forced the PNF to leave his seat to read the standby compass to determine if system #1 or #2 was good. System #1 was in agreement with standby compass so we selected CADC switch to both on #1 solving the immediate problem. We also made a PA requesting that all portable electronic devices be turned off. The abnormal procedure for heading errors was followed to no avail. About 10-15 mins after the PA about ped's when the flight attendants reported that all ped's were off, the error corrected itself and system were restored to normal. Callback conversation with reporter revealed the following information: the reporter stated the aircraft was an MD88 and was equipped with an ahrs heading system. The reporter said shortly after the announcement to turn off all electronic devices the 30 degree error was gone and the system operated normally. The reporter stated the device causing the problem was never idented.

Related reports:

Google
 

Original NASA ASRS Text

Title: AN MD88 ON TKOF AT 100 FT EXPERIENCED A HDG SPLIT OF 30 DEGS AND HAD A HDG ERROR WARNING MESSAGE CAUSED BY A PAX ELECTRONIC DEVICE.

Narrative: IMMEDIATELY AFTER TKOF, FLT MODE ANNUNCIATOR DISPLAYED A HDG ERROR MESSAGE AND A NO AUTOLAND MESSAGE WITH A 30 DEG HDG SPLIT IN R AND L HDG SYS WITH CENTRAL AIR DATA COMPUTER #2 SELECTED. IN THE ENSUING CONFUSION WE DISCOVERED THAT THE STANDBY COMPASS MIRROR IN THE STANDBY COMPASS HOUSING (LOCATED BEHIND AND ABOVE THE FO) WAS NOT PROPERLY ADJUSTED. THIS FORCED THE PNF TO LEAVE HIS SEAT TO READ THE STANDBY COMPASS TO DETERMINE IF SYS #1 OR #2 WAS GOOD. SYS #1 WAS IN AGREEMENT WITH STANDBY COMPASS SO WE SELECTED CADC SWITCH TO BOTH ON #1 SOLVING THE IMMEDIATE PROB. WE ALSO MADE A PA REQUESTING THAT ALL PORTABLE ELECTRONIC DEVICES BE TURNED OFF. THE ABNORMAL PROC FOR HDG ERRORS WAS FOLLOWED TO NO AVAIL. ABOUT 10-15 MINS AFTER THE PA ABOUT PED'S WHEN THE FLT ATTENDANTS RPTED THAT ALL PED'S WERE OFF, THE ERROR CORRECTED ITSELF AND SYS WERE RESTORED TO NORMAL. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE ACFT WAS AN MD88 AND WAS EQUIPPED WITH AN AHRS HDG SYS. THE RPTR SAID SHORTLY AFTER THE ANNOUNCEMENT TO TURN OFF ALL ELECTRONIC DEVICES THE 30 DEG ERROR WAS GONE AND THE SYS OPERATED NORMALLY. THE RPTR STATED THE DEVICE CAUSING THE PROB WAS NEVER IDENTED.

Data retrieved from NASA's ASRS site as of July 2007 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.