Narrative:

On pullman arrival to ord, very near pappi, F/a advised us of medical emergency in cabin. A passenger had stopped breathing and no pulse. While an md, emt and F/a worked cpr on passenger in aisle, we declared a medical emergency for priority in ord. We descended to 7000' and approximately 5 NM northeast of airport were given a downwind vector for 9L. During this turn the controller called traffic behind at 6000' and would get us 4000'. We were quite high for a quick landing and hearing 4000', I misunderstood and began a descent. The controller queried us and had us stop at 6000'. The first officer was trying to set up the approach and called the deviation as soon as he noted it, about 6000'. Anticipation of a quick landing, trying to coordinate with approach, F/a's and ground personnel, setting up for the approach all contributed. Approach controls vectoring for a quick approach was very good and much appreciated, but or altitude assignment left us with a lot of altitude to lose. Misunderstanding the controller's comment about getting us 4000' instead of a lower altitude, along with our desire to expedite a landing was a primary factor. Supplemental information from acn 180608: I was check airman in right seat with a new captain in the left seat. Approach control gave us heading change to a west direction. I read back the heading and requested a lower altitude. The controller responded that W4E had traffic at 6000' and we could expect lower altitude. I believe he might have mentioned 4000'. The new captain was under pressure of the medical emergency, but evidently heard what he wanted the controller to say--cleared for further descent.

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Original NASA ASRS Text

Title: ALT DEVIATION ALT EXCURSION.

Narrative: ON PULLMAN ARR TO ORD, VERY NEAR PAPPI, F/A ADVISED US OF MEDICAL EMER IN CABIN. A PAX HAD STOPPED BREATHING AND NO PULSE. WHILE AN MD, EMT AND F/A WORKED CPR ON PAX IN AISLE, WE DECLARED A MEDICAL EMER FOR PRIORITY IN ORD. WE DSNDED TO 7000' AND APPROX 5 NM NE OF ARPT WERE GIVEN A DOWNWIND VECTOR FOR 9L. DURING THIS TURN THE CTLR CALLED TFC BEHIND AT 6000' AND WOULD GET US 4000'. WE WERE QUITE HIGH FOR A QUICK LNDG AND HEARING 4000', I MISUNDERSTOOD AND BEGAN A DSNT. THE CTLR QUERIED US AND HAD US STOP AT 6000'. THE F/O WAS TRYING TO SET UP THE APCH AND CALLED THE DEVIATION AS SOON AS HE NOTED IT, ABOUT 6000'. ANTICIPATION OF A QUICK LNDG, TRYING TO COORDINATE WITH APCH, F/A'S AND GND PERSONNEL, SETTING UP FOR THE APCH ALL CONTRIBUTED. APCH CTLS VECTORING FOR A QUICK APCH WAS VERY GOOD AND MUCH APPRECIATED, BUT OR ALT ASSIGNMENT LEFT US WITH A LOT OF ALT TO LOSE. MISUNDERSTANDING THE CTLR'S COMMENT ABOUT GETTING US 4000' INSTEAD OF A LOWER ALT, ALONG WITH OUR DESIRE TO EXPEDITE A LNDG WAS A PRIMARY FACTOR. SUPPLEMENTAL INFO FROM ACN 180608: I WAS CHK AIRMAN IN RIGHT SEAT WITH A NEW CAPT IN THE LEFT SEAT. APCH CTL GAVE US HDG CHANGE TO A W DIRECTION. I READ BACK THE HDG AND REQUESTED A LOWER ALT. THE CTLR RESPONDED THAT W4E HAD TFC AT 6000' AND WE COULD EXPECT LOWER ALT. I BELIEVE HE MIGHT HAVE MENTIONED 4000'. THE NEW CAPT WAS UNDER PRESSURE OF THE MEDICAL EMER, BUT EVIDENTLY HEARD WHAT HE WANTED THE CTLR TO SAY--CLRED FOR FURTHER DSNT.

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.