IFR aircraft has near midair collision with small aircraft in clouds on airway.

Attributes
ACN	107789
Time
Date	198903
Day	Wed
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : mld
State Reference	ID
Altitude	msl bound lower : 10000 msl bound upper : 10200
Environment
Flight Conditions	IMC
Light	Dawn
Aircraft 1
Operator	common carrier : air taxi
Make Model Name	Small Transport
Flight Phase	cruise other
Route In Use	enroute airway : v21
Flight Plan	IFR
Aircraft 2
Make Model Name	Small Aircraft, High Wing, 1 Eng, Fixed Gear
Flight Phase	cruise other
Flight Plan	None
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : instrument pilot : commercial
Experience	flight time last 90 days : 210 flight time total : 18700
ASRS Report	107789
Person 2
Affiliation	Other
Function	flight crew : single pilot
Events
Anomaly	conflict : nmac inflight encounter : vfr in imc non adherence : far other spatial deviation
Independent Detector	other flight crewa
Resolutory Action	none taken : unable
Consequence	faa : investigated
Miss Distance	vertical : 200
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

I was on an IFR flight plan ZLC to pih V-21 on instruments in the clouds when center gave me traffic at 12 O'clock with a VFR code and no altitude read out. The aircraft flashed over me 100 to 200' above. I notified center that there was no way he could be VFR and they tracked him into the altitude cake area.

Original NASA ASRS Text

Title: IFR ACFT HAS NMAC WITH SMA IN CLOUDS ON AIRWAY.

Narrative: I WAS ON AN IFR FLT PLAN ZLC TO PIH V-21 ON INSTRUMENTS IN THE CLOUDS WHEN CENTER GAVE ME TFC AT 12 O'CLOCK WITH A VFR CODE AND NO ALT READ OUT. THE ACFT FLASHED OVER ME 100 TO 200' ABOVE. I NOTIFIED CENTER THAT THERE WAS NO WAY HE COULD BE VFR AND THEY TRACKED HIM INTO THE ALT CAKE AREA.

Data retrieved from NASA's ASRS site as of August 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.