Dornier 328 descending to FL230 was cleared to slow and descend to FL200. They were slowing at FL234 when an MD80 was cleared to descend to FL240. A TCASII RA resulted. ATC supervisor blamed the pilot but later found that ATC was to blame.

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Attributes
ACN	357084
Time
Date	199612
Day	Fri
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : btg airport : pdx
State Reference	WA
Altitude	msl bound lower : 23000 msl bound upper : 23400
Environment
Flight Conditions	IMC
Light	Dusk
Aircraft 1
Controlling Facilities	artcc : zse
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	cruise other descent other
Route In Use	arrival star : star
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	MD-80 Series (DC-9-80) Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	Other
Flight Phase	descent other
Route In Use	arrival star : star
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 100 flight time total : 10000 flight time type : 1000
ASRS Report	357084
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	conflict : airborne less severe non adherence : required legal separation
Independent Detector	aircraft equipment other aircraft equipment : unspecified
Resolutory Action	other
Consequence	faa : reviewed incident with flight crew
Miss Distance	vertical : 600
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

While on SID, moxee 3 into pdx, we were given clearance to FL230. While passing FL235 we were given 'slow to 200 IAS then descend and maintain FL200.' we leveled at FL234, slowed to 200 KTS and started our descent. We received an RA 'descend, descend' as MD80 stated on center they were responding to RA and could not descend to FL240 as cleared. Center then asked us our altitude. We stated FL230, descending and responding to RA. The controller then stated we leveled at FL230 and then climbed back up to FL234 to cause RA. He then gave us a vector for evasive action and the as MD80 vectors. While taxiing into pdx we were told to call center area supervisor. He stated 'my records show you descended to FL230, then climbed back up to FL234 to cause the RA.' I stated no, and stated our actions. He then replied he was playing back the tape (we waited). He then stated, 'it looks like my data supports your statement. May I have your phone number in case we need to follow up on this.' I gave it to him.

Original NASA ASRS Text

Title: DORNIER 328 DSNDING TO FL230 WAS CLRED TO SLOW AND DSND TO FL200. THEY WERE SLOWING AT FL234 WHEN AN MD80 WAS CLRED TO DSND TO FL240. A TCASII RA RESULTED. ATC SUPVR BLAMED THE PLT BUT LATER FOUND THAT ATC WAS TO BLAME.

Narrative: WHILE ON SID, MOXEE 3 INTO PDX, WE WERE GIVEN CLRNC TO FL230. WHILE PASSING FL235 WE WERE GIVEN 'SLOW TO 200 IAS THEN DSND AND MAINTAIN FL200.' WE LEVELED AT FL234, SLOWED TO 200 KTS AND STARTED OUR DSCNT. WE RECEIVED AN RA 'DSND, DSND' AS MD80 STATED ON CTR THEY WERE RESPONDING TO RA AND COULD NOT DSND TO FL240 AS CLRED. CTR THEN ASKED US OUR ALT. WE STATED FL230, DSNDING AND RESPONDING TO RA. THE CTLR THEN STATED WE LEVELED AT FL230 AND THEN CLBED BACK UP TO FL234 TO CAUSE RA. HE THEN GAVE US A VECTOR FOR EVASIVE ACTION AND THE AS MD80 VECTORS. WHILE TAXIING INTO PDX WE WERE TOLD TO CALL CTR AREA SUPVR. HE STATED 'MY RECORDS SHOW YOU DSNDED TO FL230, THEN CLBED BACK UP TO FL234 TO CAUSE THE RA.' I STATED NO, AND STATED OUR ACTIONS. HE THEN REPLIED HE WAS PLAYING BACK THE TAPE (WE WAITED). HE THEN STATED, 'IT LOOKS LIKE MY DATA SUPPORTS YOUR STATEMENT. MAY I HAVE YOUR PHONE NUMBER IN CASE WE NEED TO FOLLOW UP ON THIS.' I GAVE IT TO HIM.

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.