Narrative:

We departed iah on runway 14L. Departure instructions included turning left to a heading of 120 degrees. Upon becoming airborne, the flight director heading mode was selected and the aircraft was hand flown following the command bars. After rolling out on a 120 degree heading, the PNF commented that he had never departed iah runway 14L/right heading back over the airport. In reality, we were actually heading about 30-40 degrees, even though the compasses were indicating 120 degrees. The tower asked what heading we were flying and that it should be 120 degrees. We responded that we were heading 120 degrees. Checking the wet compass, it became obvious that we were heading about 30- 40 degrees. The tower told us to turn right and expedite our climb because we were about to overfly the runway 26 ILS final approach course. We did as we were told (quick-syncing both compass system). We were told to turn further right to a 140 degree heading. We continued without further maneuvering. Between the time the aircraft was shut down earlier in the day, until it was prepared for flight, it was reoriented 180 degrees on the FBO's ramp. During preflight, it was noted that the compass system sync indicators were not nullified, but it was thought that that might be due to magnetic interference in the area where the aircraft was parked (first error). Taxiing to the runway, both compasses were checked for agreement -- but not compared with the wet compass (second error). Taking the runway for takeoff, the PNF was completing a phone call, made while taxiing, to the company office to coordination passenger transportation while PF was completing the takeoff checklist. The runway heading was not confirmed (third error). At no time were there ever any warning flags on the compasses or lights illuminated on the comparator warning indicator. The taxi checklist will be made more specific, (instead of just 'compasses -- checked') to include the wet compass. We need to comply with established company procedures. Our operations manual addresses the concept of the sterile cockpit -- from the chocks to 10000 ft on the way up and from 10000 ft to the chocks on the way down. Calling the company while taxiing was a violation of our own operations manual and diluted the crew's attention enough to miss two opportunities to catch the compass error. Supplemental information from acn 338925: on taxi, both pilots checked the compass system and called out their heading, which was within 2 degrees of each other. What we missed was that both were misaligned by approximately 70 degrees. We should have noticed that the compass system was misaligned: at the parking stand by checking against the wet compass, taxiing on the parallel to the runway and finally as a line-up check on the runway.

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Original NASA ASRS Text

Title: A CPR MLG CREW FAILED TO ALIGN ITS COMPASS SYS PRIOR TO DEP. ERROR ADMITTED. TRACK DEV.

Narrative: WE DEPARTED IAH ON RWY 14L. DEP INSTRUCTIONS INCLUDED TURNING L TO A HDG OF 120 DEGS. UPON BECOMING AIRBORNE, THE FLT DIRECTOR HDG MODE WAS SELECTED AND THE ACFT WAS HAND FLOWN FOLLOWING THE COMMAND BARS. AFTER ROLLING OUT ON A 120 DEG HDG, THE PNF COMMENTED THAT HE HAD NEVER DEPARTED IAH RWY 14L/R HEADING BACK OVER THE ARPT. IN REALITY, WE WERE ACTUALLY HEADING ABOUT 30-40 DEGS, EVEN THOUGH THE COMPASSES WERE INDICATING 120 DEGS. THE TWR ASKED WHAT HDG WE WERE FLYING AND THAT IT SHOULD BE 120 DEGS. WE RESPONDED THAT WE WERE HDG 120 DEGS. CHKING THE WET COMPASS, IT BECAME OBVIOUS THAT WE WERE HDG ABOUT 30- 40 DEGS. THE TWR TOLD US TO TURN R AND EXPEDITE OUR CLB BECAUSE WE WERE ABOUT TO OVERFLY THE RWY 26 ILS FINAL APCH COURSE. WE DID AS WE WERE TOLD (QUICK-SYNCING BOTH COMPASS SYS). WE WERE TOLD TO TURN FURTHER R TO A 140 DEG HDG. WE CONTINUED WITHOUT FURTHER MANEUVERING. BTWN THE TIME THE ACFT WAS SHUT DOWN EARLIER IN THE DAY, UNTIL IT WAS PREPARED FOR FLT, IT WAS REORIENTED 180 DEGS ON THE FBO'S RAMP. DURING PREFLT, IT WAS NOTED THAT THE COMPASS SYS SYNC INDICATORS WERE NOT NULLIFIED, BUT IT WAS THOUGHT THAT THAT MIGHT BE DUE TO MAGNETIC INTERFERENCE IN THE AREA WHERE THE ACFT WAS PARKED (FIRST ERROR). TAXIING TO THE RWY, BOTH COMPASSES WERE CHKED FOR AGREEMENT -- BUT NOT COMPARED WITH THE WET COMPASS (SECOND ERROR). TAKING THE RWY FOR TKOF, THE PNF WAS COMPLETING A PHONE CALL, MADE WHILE TAXIING, TO THE COMPANY OFFICE TO COORD PAX TRANSPORTATION WHILE PF WAS COMPLETING THE TKOF CHKLIST. THE RWY HDG WAS NOT CONFIRMED (THIRD ERROR). AT NO TIME WERE THERE EVER ANY WARNING FLAGS ON THE COMPASSES OR LIGHTS ILLUMINATED ON THE COMPARATOR WARNING INDICATOR. THE TAXI CHKLIST WILL BE MADE MORE SPECIFIC, (INSTEAD OF JUST 'COMPASSES -- CHKED') TO INCLUDE THE WET COMPASS. WE NEED TO COMPLY WITH ESTABLISHED COMPANY PROCS. OUR OPS MANUAL ADDRESSES THE CONCEPT OF THE STERILE COCKPIT -- FROM THE CHOCKS TO 10000 FT ON THE WAY UP AND FROM 10000 FT TO THE CHOCKS ON THE WAY DOWN. CALLING THE COMPANY WHILE TAXIING WAS A VIOLATION OF OUR OWN OPS MANUAL AND DILUTED THE CREW'S ATTN ENOUGH TO MISS TWO OPPORTUNITIES TO CATCH THE COMPASS ERROR. SUPPLEMENTAL INFO FROM ACN 338925: ON TAXI, BOTH PLTS CHKED THE COMPASS SYS AND CALLED OUT THEIR HDG, WHICH WAS WITHIN 2 DEGS OF EACH OTHER. WHAT WE MISSED WAS THAT BOTH WERE MISALIGNED BY APPROX 70 DEGS. WE SHOULD HAVE NOTICED THAT THE COMPASS SYS WAS MISALIGNED: AT THE PARKING STAND BY CHKING AGAINST THE WET COMPASS, TAXIING ON THE PARALLEL TO THE RWY AND FINALLY AS A LINE-UP CHK ON THE RWY.

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.