C560 crew and a straight tail bonanza had a near midair collision in C90 class east.

Attributes
ACN	586600
Time
Date	200307
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : c90.tracon
State Reference	IL
Altitude	msl single value : 4000
Environment
Flight Conditions	IMC
Weather Elements	Thunderstorm
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : c90.tracon
Operator	general aviation : corporate
Make Model Name	Citation V
Operating Under FAR Part	Part 91
Navigation In Use	other
Flight Phase	descent : holding descent : approach descent : intermediate altitude
Route In Use	arrival : on vectors
Flight Plan	IFR
Aircraft 2
Controlling Facilities	tracon : c90.tracon
Make Model Name	Beechcraft Single Piston Undifferentiated or Other Model
Operating Under FAR Part	Part 91
Flight Phase	cruise : level
Person 1
Affiliation	company : corporate
Function	flight crew : first officer
Qualification	pilot : multi engine pilot : atp
Experience	flight time last 90 days : 100 flight time total : 4800 flight time type : 500
ASRS Report	586600
Person 2
Affiliation	company : corporate
Function	flight crew : captain oversight : pic
Events
Anomaly	altitude deviation : excursion from assigned altitude conflict : nmac inflight encounter : vfr in imc inflight encounter : weather inflight encounter other non adherence : required legal separation non adherence : published procedure non adherence : far other anomaly other
Independent Detector	aircraft equipment : tcas other flight crewa other flight crewb
Resolutory Action	flight crew : took evasive action other
Miss Distance	horizontal : 200 vertical : 400
Supplementary
Problem Areas	Weather Flight Crew Human Performance ATC Human Performance
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation other

Narrative:

After holding at krena int. To wait out thunderstorms at pwk, we were given a vector to the ILS 16 at pwk. We were then told to turn to a 40 degree heading. We told the controller that the heading would put us in the WX. We were told to 'turn northwest.' I asked for a suggested heading, and was told to 'turn west.' I queried the controller if he wanted us on a 270 degree heading 4 separate times with no answer. The controller answered several other aircraft while I was asking for clarification, and would not answer me. After about 5 mins on a 270 degree heading, we got a TA. At this point, we were IMC. The mfd indicated a target at 12-1 O'clock, less than 1 mi and 100 ft below. I advised the captain to climb. As we started to climb, the controller called the traffic, and we informed him that we had received a TA and were climbing. I finally got the traffic in sight. It was white with red and blue stripes, and appeared to be a straight tail bonanza. I hope controller overload was a factor in this occurrence. There was not much that we could have done since we were in and out of IMC, and not given vectors. We were simply told 'turn west.' by being obstinate, frustrated, or simply losing track of us, this controller put my life, the lives of my other crew member, and passenger, and the lives of the other aircraft's occupants in danger. The other pilot also endangered all involved by flying at an IFR altitude without being on an IFR flight plan or in radio contact.

Original NASA ASRS Text

Title: C560 CREW AND A STRAIGHT TAIL BONANZA HAD A NMAC IN C90 CLASS E.

Narrative: AFTER HOLDING AT KRENA INT. TO WAIT OUT TSTMS AT PWK, WE WERE GIVEN A VECTOR TO THE ILS 16 AT PWK. WE WERE THEN TOLD TO TURN TO A 40 DEG HDG. WE TOLD THE CTLR THAT THE HDG WOULD PUT US IN THE WX. WE WERE TOLD TO 'TURN NW.' I ASKED FOR A SUGGESTED HDG, AND WAS TOLD TO 'TURN W.' I QUERIED THE CTLR IF HE WANTED US ON A 270 DEG HDG 4 SEPARATE TIMES WITH NO ANSWER. THE CTLR ANSWERED SEVERAL OTHER ACFT WHILE I WAS ASKING FOR CLARIFICATION, AND WOULD NOT ANSWER ME. AFTER ABOUT 5 MINS ON A 270 DEG HDG, WE GOT A TA. AT THIS POINT, WE WERE IMC. THE MFD INDICATED A TARGET AT 12-1 O'CLOCK, LESS THAN 1 MI AND 100 FT BELOW. I ADVISED THE CAPT TO CLB. AS WE STARTED TO CLB, THE CTLR CALLED THE TFC, AND WE INFORMED HIM THAT WE HAD RECEIVED A TA AND WERE CLBING. I FINALLY GOT THE TFC IN SIGHT. IT WAS WHITE WITH RED AND BLUE STRIPES, AND APPEARED TO BE A STRAIGHT TAIL BONANZA. I HOPE CTLR OVERLOAD WAS A FACTOR IN THIS OCCURRENCE. THERE WAS NOT MUCH THAT WE COULD HAVE DONE SINCE WE WERE IN AND OUT OF IMC, AND NOT GIVEN VECTORS. WE WERE SIMPLY TOLD 'TURN W.' BY BEING OBSTINATE, FRUSTRATED, OR SIMPLY LOSING TRACK OF US, THIS CTLR PUT MY LIFE, THE LIVES OF MY OTHER CREW MEMBER, AND PAX, AND THE LIVES OF THE OTHER ACFT'S OCCUPANTS IN DANGER. THE OTHER PLT ALSO ENDANGERED ALL INVOLVED BY FLYING AT AN IFR ALT WITHOUT BEING ON AN IFR FLT PLAN OR IN RADIO CONTACT.

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.