ZAU controller described departure aircraft tracking anomaly suggesting that MD80 series aircraft fr...

Narrative:

I work at ZAU. One of our sectors is the west departure corridor out of ord. We work wbound departures from ord and mdw plus the satellite airports around chicago. The airspace is narrow and planes climb out and are put in different corridors. I have noticed that MD82's that come out and track left of course (ie; 2 aircraft on 270 degree headings the MD82 will track a 260 degree heading even though assigned a 270 degree heading). I have observed this in normal westerly winds and strong north and south wind. The MD82's track to the left in all winds. I have asked my co-workers to look for this and they concur. This is very dangerous in a small sector like this where you are climbing aircraft on parallel headings and could lead to a loss of separation if it has not already. The sector this occurs at owns 11000 ft up to FL230 and typically gets aircraft from chicago TRACON out of 9000 ft climbing to 13000 ft.

Original NASA ASRS Text

Title: ZAU CTLR DESCRIBED DEP ACFT TRACKING ANOMALY SUGGESTING THAT MD80 SERIES ACFT FROM ORD/MDW ARE FREQUENTLY LEFT OF THE EXPECTED COURSE.

Narrative: I WORK AT ZAU. ONE OF OUR SECTORS IS THE W DEP CORRIDOR OUT OF ORD. WE WORK WBOUND DEPS FROM ORD AND MDW PLUS THE SATELLITE ARPTS AROUND CHICAGO. THE AIRSPACE IS NARROW AND PLANES CLB OUT AND ARE PUT IN DIFFERENT CORRIDORS. I HAVE NOTICED THAT MD82'S THAT COME OUT AND TRACK L OF COURSE (IE; 2 ACFT ON 270 DEG HDGS THE MD82 WILL TRACK A 260 DEG HDG EVEN THOUGH ASSIGNED A 270 DEG HDG). I HAVE OBSERVED THIS IN NORMAL WESTERLY WINDS AND STRONG N AND S WIND. THE MD82'S TRACK TO THE L IN ALL WINDS. I HAVE ASKED MY CO-WORKERS TO LOOK FOR THIS AND THEY CONCUR. THIS IS VERY DANGEROUS IN A SMALL SECTOR LIKE THIS WHERE YOU ARE CLBING ACFT ON PARALLEL HDGS AND COULD LEAD TO A LOSS OF SEPARATION IF IT HAS NOT ALREADY. THE SECTOR THIS OCCURS AT OWNS 11000 FT UP TO FL230 AND TYPICALLY GETS ACFT FROM CHICAGO TRACON OUT OF 9000 FT CLBING TO 13000 FT.

Data retrieved from NASA's ASRS site as of May 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.

Attributes
ACN	770135
Time
Date	200801
Place
Locale Reference	atc facility : zau.artcc
State Reference	IL
Person 1
Affiliation	government : faa
Function	controller : radar
ASRS Report	770135
Events
Anomaly	other spatial deviation
Independent Detector	other controllera other flight crewa
Resolutory Action	none taken : anomaly accepted
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

ZAU controller described departure aircraft tracking anomaly suggesting that MD80 series aircraft from ord/mdw are frequently left of the expected course.