Atx pilot flies into forecast icing conditions in aircraft not equipped to deal with icing.

Attributes
ACN	283581
Time
Date	199409
Day	Thu
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : sgf
State Reference	MO
Altitude	msl bound lower : 4500 msl bound upper : 8000
Environment
Flight Conditions	IMC
Light	Night
Aircraft 1
Controlling Facilities	artcc : zhu
Operator	common carrier : air taxi
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 135
Flight Phase	cruise other descent other ground : preflight
Route In Use	enroute airway : zkc
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : commercial pilot : instrument
Experience	flight time last 90 days : 100 flight time total : 2000 flight time type : 15
ASRS Report	283581
Person 2
Affiliation	government : faa
Function	other personnel other
Qualification	other
Events
Anomaly	aircraft equipment problem : critical inflight encounter : weather non adherence : far other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : exited adverse environment
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

During a WX briefing, I was told by a briefer that there was an airmet for possible light to moderate icing from 500 to 900 ft up to 20000 ft MSL. However, the briefer pointed out that there were no pilot reports of icing along that route, so I filed for and received a clearance for 8000 ft MSL from sgf to mkc. During the flight at 8000 ft I noticed the outside air temperature from my temperature probe was near freezing so I requested a lower altitude and received clearance to 6000 ft. After approximately 15 mins I started to pick up a trace to light accumulation of rime ice. I requested a lower altitude again and was cleared to 4000 MSL. I popped out of the bases at 4500 and all of the accumulation was gone. I continued the flight to my destination without incident. The problem arose from the misunderstanding of flight into known icing conditions. My aircraft is not equipped with deice/anti-ice and the aircraft manual states not approved for known icing. However, known icing is not defined. I found out through a fellow pilot that flight into known or forecast icing is not approved, unless deice equipment is on board and special certification of equipment is required for known icing. I think many pilots are confused about what known icing is, perhaps making that information more ready available through advisory circulars or bulletins, especially since the icing season is approaching.

Original NASA ASRS Text

Title: ATX PLT FLIES INTO FORECAST ICING CONDITIONS IN ACFT NOT EQUIPPED TO DEAL WITH ICING.

Narrative: DURING A WX BRIEFING, I WAS TOLD BY A BRIEFER THAT THERE WAS AN AIRMET FOR POSSIBLE LIGHT TO MODERATE ICING FROM 500 TO 900 FT UP TO 20000 FT MSL. HOWEVER, THE BRIEFER POINTED OUT THAT THERE WERE NO PLT RPTS OF ICING ALONG THAT RTE, SO I FILED FOR AND RECEIVED A CLRNC FOR 8000 FT MSL FROM SGF TO MKC. DURING THE FLT AT 8000 FT I NOTICED THE OUTSIDE AIR TEMP FROM MY TEMP PROBE WAS NEAR FREEZING SO I REQUESTED A LOWER ALT AND RECEIVED CLRNC TO 6000 FT. AFTER APPROX 15 MINS I STARTED TO PICK UP A TRACE TO LIGHT ACCUMULATION OF RIME ICE. I REQUESTED A LOWER ALT AGAIN AND WAS CLRED TO 4000 MSL. I POPPED OUT OF THE BASES AT 4500 AND ALL OF THE ACCUMULATION WAS GONE. I CONTINUED THE FLT TO MY DEST WITHOUT INCIDENT. THE PROB AROSE FROM THE MISUNDERSTANDING OF FLT INTO KNOWN ICING CONDITIONS. MY ACFT IS NOT EQUIPPED WITH DEICE/ANTI-ICE AND THE ACFT MANUAL STATES NOT APPROVED FOR KNOWN ICING. HOWEVER, KNOWN ICING IS NOT DEFINED. I FOUND OUT THROUGH A FELLOW PLT THAT FLT INTO KNOWN OR FORECAST ICING IS NOT APPROVED, UNLESS DEICE EQUIP IS ON BOARD AND SPECIAL CERTIFICATION OF EQUIP IS REQUIRED FOR KNOWN ICING. I THINK MANY PLTS ARE CONFUSED ABOUT WHAT KNOWN ICING IS, PERHAPS MAKING THAT INFO MORE READY AVAILABLE THROUGH ADVISORY CIRCULARS OR BULLETINS, ESPECIALLY SINCE THE ICING SEASON IS APCHING.

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.