S80 flight crew uses omega below FL180 opposed to company procedures. Heading deviation results.

Attributes
ACN	340220
Time
Date	199606
Day	Sat
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : oxi
State Reference	IN
Altitude	msl bound lower : 15000 msl bound upper : 15000
Aircraft 1
Controlling Facilities	artcc : zau
Operator	common carrier : air carrier
Make Model Name	MD-80 Super 80
Operating Under FAR Part	Part 121
Navigation In Use	Other
Flight Phase	descent other
Route In Use	enroute : on vectors enroute : direct
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	340220
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	non adherence : clearance other spatial deviation
Independent Detector	other flight crewa
Resolutory Action	flight crew : became reoriented
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

En route to ord at okk cleared direct to oxi and then cleared direct to bears intersection. PNF accept direct, aircraft was at FL280. Then cleared to FL240 and finally to 16000 ft. While in descent crew got busy with checklist and also checking out localizer approach to runway 27L which was in use. The use of the omega was forgotten to be not allowed below 18000 ft. At 16000 ft given to cross 5 mi southeast of bears at 11000 ft. At about 15000 ft remembered that omega could not be used below 18000 ft and began to navigation point to point on VOR radials. Wind took aircraft east of direct line to bears and intercepted oxi 297 degree radial before bears intersection at about 12 mi southeast of bears. Lesson learned is to not accept any intersection on arrival or departure unless you are sure you will be at or above 18000 ft. Also I will have to watch fixes when at altitude and accepting direct farther out. Also it would be good to advise ord center that MD80 aircraft will be unable to accept direct to intxns on arrs so they can plan ahead. It appears that flow into certain cities are now planned for direct when all are coming from the same direction and MD80 is following B757, B737 and F100 traffic.

Original NASA ASRS Text

Title: S80 FLC USES OMEGA BELOW FL180 OPPOSED TO COMPANY PROCS. HDG DEV RESULTS.

Narrative: ENRTE TO ORD AT OKK CLRED DIRECT TO OXI AND THEN CLRED DIRECT TO BEARS INTXN. PNF ACCEPT DIRECT, ACFT WAS AT FL280. THEN CLRED TO FL240 AND FINALLY TO 16000 FT. WHILE IN DSCNT CREW GOT BUSY WITH CHKLIST AND ALSO CHKING OUT LOC APCH TO RWY 27L WHICH WAS IN USE. THE USE OF THE OMEGA WAS FORGOTTEN TO BE NOT ALLOWED BELOW 18000 FT. AT 16000 FT GIVEN TO CROSS 5 MI SE OF BEARS AT 11000 FT. AT ABOUT 15000 FT REMEMBERED THAT OMEGA COULD NOT BE USED BELOW 18000 FT AND BEGAN TO NAV POINT TO POINT ON VOR RADIALS. WIND TOOK ACFT E OF DIRECT LINE TO BEARS AND INTERCEPTED OXI 297 DEG RADIAL BEFORE BEARS INTXN AT ABOUT 12 MI SE OF BEARS. LESSON LEARNED IS TO NOT ACCEPT ANY INTXN ON ARR OR DEP UNLESS YOU ARE SURE YOU WILL BE AT OR ABOVE 18000 FT. ALSO I WILL HAVE TO WATCH FIXES WHEN AT ALT AND ACCEPTING DIRECT FARTHER OUT. ALSO IT WOULD BE GOOD TO ADVISE ORD CTR THAT MD80 ACFT WILL BE UNABLE TO ACCEPT DIRECT TO INTXNS ON ARRS SO THEY CAN PLAN AHEAD. IT APPEARS THAT FLOW INTO CERTAIN CITIES ARE NOW PLANNED FOR DIRECT WHEN ALL ARE COMING FROM THE SAME DIRECTION AND MD80 IS FOLLOWING B757, B737 AND F100 TFC.

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.