Narrative:

We were on the last leg of a 7 day european trip and flying to reykjavik. On the descent; we had thought we heard qnh 29.86 from ATIS. We also heard what we thought was qnh 29.86 from the approach controller during our descent eventually to 4000 ft. A few seconds after leveling at 4000 ft; the controller said he showed us at 3400 ft. We checked our altimeters and settings at 4000 ft on qnh 29.86. A few seconds later we heard the egpws pull-up command and responded by climbing 1000 ft. Shortly after climbing; we broke into VMC; saw the aircraft and landed. What ATIS and the controller had been saying was qnh 0986; a very low setting (29.09 inches). The danish accented english made it sound like 29.86 and there was no reference to inches or hectopascals. We should have caught this by being alert to expect hectopascals as per the approach chart. We also could have referenced the preflight metar report or confirmed inches or hectopascals on the radio with reykjavik. On departure; ATIS broadcast both hectopascals and inches for qnh.

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Original NASA ASRS Text

Title: C750 FLT CREW EXPERIENCED EGPWS PULL UP COMMAND ON DSCNT INTO BIRK AFTER THEY MISTOOK ALTIMETER SETTING 0986 HECTOPASCALS FOR 29 PT 86 INCHES HG.

Narrative: WE WERE ON THE LAST LEG OF A 7 DAY EUROPEAN TRIP AND FLYING TO REYKJAVIK. ON THE DSCNT; WE HAD THOUGHT WE HEARD QNH 29.86 FROM ATIS. WE ALSO HEARD WHAT WE THOUGHT WAS QNH 29.86 FROM THE APCH CTLR DURING OUR DSCNT EVENTUALLY TO 4000 FT. A FEW SECONDS AFTER LEVELING AT 4000 FT; THE CTLR SAID HE SHOWED US AT 3400 FT. WE CHKED OUR ALTIMETERS AND SETTINGS AT 4000 FT ON QNH 29.86. A FEW SECONDS LATER WE HEARD THE EGPWS PULL-UP COMMAND AND RESPONDED BY CLBING 1000 FT. SHORTLY AFTER CLBING; WE BROKE INTO VMC; SAW THE ACFT AND LANDED. WHAT ATIS AND THE CTLR HAD BEEN SAYING WAS QNH 0986; A VERY LOW SETTING (29.09 INCHES). THE DANISH ACCENTED ENGLISH MADE IT SOUND LIKE 29.86 AND THERE WAS NO REF TO INCHES OR HECTOPASCALS. WE SHOULD HAVE CAUGHT THIS BY BEING ALERT TO EXPECT HECTOPASCALS AS PER THE APCH CHART. WE ALSO COULD HAVE REFED THE PREFLT METAR RPT OR CONFIRMED INCHES OR HECTOPASCALS ON THE RADIO WITH REYKJAVIK. ON DEP; ATIS BROADCAST BOTH HECTOPASCALS AND INCHES FOR QNH.

Data retrieved from NASA's ASRS site as of January 2009 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.