DO328 flight crew received a TCASII RA at FL230 from what appeared to be crossing traffic overhead.

Attributes
ACN	445244
Time
Date	199908
Day	Fri
Local Time Of Day	1201 To 1800
Place
Locale Reference	navaid : vwv.vor
State Reference	OH
Altitude	msl bound lower : 22500 msl bound upper : 23200
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zob.artcc
Operator	common carrier : air carrier
Make Model Name	Do 328 TP (Turboprop)
Operating Under FAR Part	Part 121
Flight Phase	cruise : level
Flight Plan	IFR
Aircraft 2
Controlling Facilities	artcc : zob.artcc
Make Model Name	Commercial Fixed Wing
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 240 flight time total : 7300 flight time type : 2800
ASRS Report	445244
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument pilot : multi engine
Events
Anomaly	altitude deviation : excursion from assigned altitude conflict : nmac conflict : airborne critical non adherence : published procedure
Independent Detector	aircraft equipment : tcas other controllera other controllerb
Resolutory Action	flight crew : returned to assigned altitude flight crew : took evasive action
Miss Distance	horizontal : 1000 vertical : 200
Supplementary
Problem Areas	ATC Human Performance
Primary Problem	ATC Human Performance

Narrative:

We received an RA and rapidly descended about 500 ft until advised by TCASII to be clear of conflict. I'm not sure where the other aircraft was going (climbing or descending). It was difficult to tell the details of the other aircraft since its location was obscured by our aircraft symbol on the TCASII display. When it had moved away it was 200 ft above us. We were eastbound, it was sbound. We advised ZOB on 119.95 of our altitude deviation and RA and were instructed to return to FL230.

Original NASA ASRS Text

Title: DO328 FLC RECEIVED A TCASII RA AT FL230 FROM WHAT APPEARED TO BE XING TFC OVERHEAD.

Narrative: WE RECEIVED AN RA AND RAPIDLY DSNDED ABOUT 500 FT UNTIL ADVISED BY TCASII TO BE CLR OF CONFLICT. I'M NOT SURE WHERE THE OTHER ACFT WAS GOING (CLBING OR DSNDING). IT WAS DIFFICULT TO TELL THE DETAILS OF THE OTHER ACFT SINCE ITS LOCATION WAS OBSCURED BY OUR ACFT SYMBOL ON THE TCASII DISPLAY. WHEN IT HAD MOVED AWAY IT WAS 200 FT ABOVE US. WE WERE EBOUND, IT WAS SBOUND. WE ADVISED ZOB ON 119.95 OF OUR ALTDEV AND RA AND WERE INSTRUCTED TO RETURN TO FL230.

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.