Narrative:

Cruising at FL210, ATC gave us (on route dca to hpn) a clearance to cross bouno intersection at 17000 ft with an altimeter setting of 29.31. I put 29.31 in the standby altimeter and planned to put 29.31 in the primary altimeter out of FL180. After leveling at 17000 ft, a few mins later ATC asked me the altitude. I said 17000 ft. He said what is your altimeter setting? I then said yes, I need to correct the setting. I asked if there was any problem and he said everything was ok, and I thanked him for his help. In the descent, I had become preoccupied with other duties and should have paid closer attention to passing FL180 for the altimeter change.

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Original NASA ASRS Text

Title: FLC OF COMMUTER ACFT FAIL TO CHANGE ALTIMETER SETTING WHEN PASSING THROUGH FL180. XING RESTR MISSED.

Narrative: CRUISING AT FL210, ATC GAVE US (ON RTE DCA TO HPN) A CLRNC TO CROSS BOUNO INTXN AT 17000 FT WITH AN ALTIMETER SETTING OF 29.31. I PUT 29.31 IN THE STANDBY ALTIMETER AND PLANNED TO PUT 29.31 IN THE PRIMARY ALTIMETER OUT OF FL180. AFTER LEVELING AT 17000 FT, A FEW MINS LATER ATC ASKED ME THE ALT. I SAID 17000 FT. HE SAID WHAT IS YOUR ALTIMETER SETTING? I THEN SAID YES, I NEED TO CORRECT THE SETTING. I ASKED IF THERE WAS ANY PROB AND HE SAID EVERYTHING WAS OK, AND I THANKED HIM FOR HIS HELP. IN THE DSCNT, I HAD BECOME PREOCCUPIED WITH OTHER DUTIES AND SHOULD HAVE PAID CLOSER ATTN TO PASSING FL180 FOR THE ALTIMETER CHANGE.

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.