Loss of separation between reporter's B757 at FL290 and a descending air carrier DC9.

Attributes
ACN	397677
Time
Date	199803
Day	Tue
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : fod
State Reference	IA
Altitude	msl bound lower : 29000 msl bound upper : 29000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zmp
Operator	common carrier : air carrier
Make Model Name	B757 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	cruise other cruise other descent other
Route In Use	enroute : on vectors
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	DC-9 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	descent other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : cfi pilot : commercial pilot : instrument pilot : atp
Experience	flight time last 90 days : 80 flight time total : 8000 flight time type : 420
ASRS Report	397677
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	conflict : airborne less severe non adherence : published procedure non adherence : required legal separation other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified other controllera
Resolutory Action	controller : issued new clearance flight crew : took evasive action other
Consequence	Other
Miss Distance	horizontal : 12000 vertical : 500
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

In right turn to flight plan/cleared route FOD-dbq level cruise at FL290, center issues left 30 degree heading change. While aircraft rolling from right to left bank, center asks to tighten turn. Within 30 seconds, TCASII TA, then 'descend' RA, then 'increase descent' RA. 'Clear of conflict' at FL285. During RA maneuver, acquired other aircraft visually. TCASII indications were appropriate and timely. Other aircraft apparently was descending intentionally.

Original NASA ASRS Text

Title: LOSS OF SEPARATION BTWN RPTR'S B757 AT FL290 AND A DSNDING ACR DC9.

Narrative: IN R TURN TO FLT PLAN/CLRED RTE FOD-DBQ LEVEL CRUISE AT FL290, CTR ISSUES L 30 DEG HDG CHANGE. WHILE ACFT ROLLING FROM R TO L BANK, CTR ASKS TO TIGHTEN TURN. WITHIN 30 SECONDS, TCASII TA, THEN 'DSND' RA, THEN 'INCREASE DSCNT' RA. 'CLR OF CONFLICT' AT FL285. DURING RA MANEUVER, ACQUIRED OTHER ACFT VISUALLY. TCASII INDICATIONS WERE APPROPRIATE AND TIMELY. OTHER ACFT APPARENTLY WAS DSNDING INTENTIONALLY.

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.