|37000 Feet||Browse and search NASA's
Aviation Safety Reporting System
|Local Time Of Day||0601 To 1200|
|Locale Reference||atc facility : eon|
|Altitude||msl bound lower : 4700|
msl bound upper : 5000
|Controlling Facilities||artcc : zau|
|Operator||general aviation : personal|
|Make Model Name||Small Aircraft, High Wing, 1 Eng, Fixed Gear|
|Flight Phase||cruise other|
|Function||flight crew : single pilot|
|Qualification||pilot : instrument|
pilot : commercial
|Experience||flight time last 90 days : 100|
flight time total : 1500
flight time type : 10
|Affiliation||government : faa|
|Function||controller : radar|
|Qualification||controller : radar|
|Anomaly||altitude deviation : excursion from assigned altitude|
non adherence : clearance
|Independent Detector||other controllera|
other flight crewa
|Resolutory Action||flight crew : returned to intended course or assigned course|
|Primary Problem||Flight Crew Human Performance|
|Air Traffic Incident||Pilot Deviation|
Assigned 5000' which put me 1000' on top (tops 4000') with high thin cirrus above. While maintain a lookout for other traffic, since I was VMC, my INS scan became a little lax and I slipped down in altitude. I caught myself at 240' low and ATC called me at 300' low. I had started back to my assigned altitude and ATC gave me a new altimeter setting, then said, 'ok, I have you level now.' my perception is work harder at the INS scan and maintain the altitude. The only other aircraft around would also be on radar and ATC would call them out to me (I hope). A contributing factor--the aircraft is not equipped with autoplt.
Original NASA ASRS Text
Title: SMA PLT ON IFR FLT PLAN DEVIATES FROM ASSIGNED ALT.
Narrative: ASSIGNED 5000' WHICH PUT ME 1000' ON TOP (TOPS 4000') WITH HIGH THIN CIRRUS ABOVE. WHILE MAINTAIN A LOOKOUT FOR OTHER TFC, SINCE I WAS VMC, MY INS SCAN BECAME A LITTLE LAX AND I SLIPPED DOWN IN ALT. I CAUGHT MYSELF AT 240' LOW AND ATC CALLED ME AT 300' LOW. I HAD STARTED BACK TO MY ASSIGNED ALT AND ATC GAVE ME A NEW ALTIMETER SETTING, THEN SAID, 'OK, I HAVE YOU LEVEL NOW.' MY PERCEPTION IS WORK HARDER AT THE INS SCAN AND MAINTAIN THE ALT. THE ONLY OTHER ACFT AROUND WOULD ALSO BE ON RADAR AND ATC WOULD CALL THEM OUT TO ME (I HOPE). A CONTRIBUTING FACTOR--THE ACFT IS NOT EQUIPPED WITH AUTOPLT.
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.