Near midair collision between a DC9 in an arrival holding pattern and a saab 340 descending to the same altitude. TCASII RA warned the DC9 crew that the saab was descending in the opposite direction and the crew subsequently observed the saab and took evasive action.

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Attributes
ACN	429487
Time
Date	199902
Day	Thu
Local Time Of Day	0601 To 1200
Place
Locale Reference	navaid : aco.vor
State Reference	OH
Altitude	msl single value : 13000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zob.artcc tracon : d10.tracon
Operator	common carrier : air carrier
Make Model Name	DC-9 30
Operating Under FAR Part	Part 121
Flight Phase	descent : holding
Route In Use	arrival : holding pattern
Flight Plan	IFR
Aircraft 2
Controlling Facilities	artcc : zob.artcc
Operator	common carrier : air carrier
Make Model Name	SF 340A
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 : atp pilot : flight engineer pilot : multi engine
Experience	flight time last 90 days : 173 flight time total : 14374 flight time type : 5106
ASRS Report	429487
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument pilot : multi engine
Events
Anomaly	conflict : nmac non adherence : published procedure non adherence : required legal separation
Independent Detector	aircraft equipment : tcas other flight crewa
Resolutory Action	flight crew : took evasive action
Miss Distance	horizontal : 200 vertical : 0
Supplementary
Problem Areas	ATC Human Performance
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

We were holding at cutta intersection at 13000 ft MSL. Saw on TCASII aircraft descending through 14000 ft and acquired aircraft visually at 1 O'clock high. Aircraft continued to descend to 13000 ft causing our TCASII to issue an RA while I was getting a lower altitude from ZOB. I don't know the cause of this loss of separation. Our last cleared altitude was 13000 ft. Pit airport had just closed for snow removal and the controller was very busy issuing holding clrncs. I don't know if the controller forgot about us or if the saab descended to the wrong altitude. I heard and responded to no other clrncs for us and heard no other clrncs issued to 13000 ft on our frequency.

Original NASA ASRS Text

Title: NMAC BTWN A DC9 IN AN ARR HOLDING PATTERN AND A SAAB 340 DSNDING TO THE SAME ALT. TCASII RA WARNED THE DC9 CREW THAT THE SAAB WAS DSNDING IN THE OPPOSITE DIRECTION AND THE CREW SUBSEQUENTLY OBSERVED THE SAAB AND TOOK EVASIVE ACTION.

Narrative: WE WERE HOLDING AT CUTTA INTXN AT 13000 FT MSL. SAW ON TCASII ACFT DSNDING THROUGH 14000 FT AND ACQUIRED ACFT VISUALLY AT 1 O'CLOCK HIGH. ACFT CONTINUED TO DSND TO 13000 FT CAUSING OUR TCASII TO ISSUE AN RA WHILE I WAS GETTING A LOWER ALT FROM ZOB. I DON'T KNOW THE CAUSE OF THIS LOSS OF SEPARATION. OUR LAST CLRED ALT WAS 13000 FT. PIT ARPT HAD JUST CLOSED FOR SNOW REMOVAL AND THE CTLR WAS VERY BUSY ISSUING HOLDING CLRNCS. I DON'T KNOW IF THE CTLR FORGOT ABOUT US OR IF THE SAAB DSNDED TO THE WRONG ALT. I HEARD AND RESPONDED TO NO OTHER CLRNCS FOR US AND HEARD NO OTHER CLRNCS ISSUED TO 13000 FT ON OUR FREQ.

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.