Pilot instructor in small aircraft on training flight encountered icing, but ATC unable lower accoun...

Attributes
ACN	135800
Time
Date	199002
Day	Mon
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : pae
State Reference	WA
Altitude	msl bound lower : 3800 msl bound upper : 4000
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zse
Operator	general aviation : instructional
Make Model Name	Small Aircraft, High Wing, 1 Eng, Fixed Gear
Flight Phase	cruise other descent : approach
Route In Use	enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Events
Anomaly	altitude deviation : excursion from assigned altitude inflight encounter : weather inflight encounter other non adherence : clearance other anomaly
Independent Detector	other other : unspecified cockpit
Resolutory Action	controller : issued new clearance other
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

I was on an IFR student training flight. We were cleared to 4000' and direct to ritts LOM for a couple of practice NDB 16R approachs into paine field. At 4000', right after we crossed ritts, we were told to remain at 4000' and proceed outbnd and the 337 degree bearing to expect further clearance in 7 mi. This was due to a jet on the ILS approach below us and in front of us heading inbound at 3000'. We entered IMC conditions immediately upon receiving that clearance. Even though we had not encountered any rain outside of the clouds, there was a significant amount of precipitation in the clouds. With the freezing level at 3000' we started to accumulate clear mixed with rime ice at a very rapid rate. I assessed the situation and determined that at the rate we were accumulating ice, we would not be able to stay at 4000' for the next 7 mi. I requested a lower altitude due to the ice and center told me unable. The jet had not passed below us. At this pint I had applied full power to the small aircraft and resolved to hold my altitude until my airspeed dropped to 80 KIAS. This I did and all the while requested a lower altitude. When my airspeed reached 80 KIAS, I again requested a lower altitude, and they replied that due to the jet, which was at this time passing under, they would not until another 2 mi. At this point I said that 'like it or not, I'm coming down anyway cause I can't hold altitude.' he asked if I would like to declare an emergency, but I said no. When I was down to 3800', he vectored me off the approach and gave me a descent down to 2000', so I deviated my altitude by 200' before he gave me a lower, and this deviation was done west/O declaring an emergency. I suppose I could have asked for vectors away from the approach, or have declared an emergency because I really didn't know how much ice I had. After I landed, we still had 2' along the leading edge.

Original NASA ASRS Text

Title: PLT INSTRUCTOR IN SMA ON TRAINING FLT ENCOUNTERED ICING, BUT ATC UNABLE LOWER ACCOUNT TRAFFIC. PLT DID NOT DECLARE EMERGENCY, BUT DESCENDED OUT OF ASSIGNED ALT.

Narrative: I WAS ON AN IFR STUDENT TRNING FLT. WE WERE CLRED TO 4000' AND DIRECT TO RITTS LOM FOR A COUPLE OF PRACTICE NDB 16R APCHS INTO PAINE FIELD. AT 4000', RIGHT AFTER WE CROSSED RITTS, WE WERE TOLD TO REMAIN AT 4000' AND PROCEED OUTBND AND THE 337 DEG BEARING TO EXPECT FURTHER CLRNC IN 7 MI. THIS WAS DUE TO A JET ON THE ILS APCH BELOW US AND IN FRONT OF US HDG INBND AT 3000'. WE ENTERED IMC CONDITIONS IMMEDIATELY UPON RECEIVING THAT CLRNC. EVEN THOUGH WE HAD NOT ENCOUNTERED ANY RAIN OUTSIDE OF THE CLOUDS, THERE WAS A SIGNIFICANT AMOUNT OF PRECIPITATION IN THE CLOUDS. WITH THE FREEZING LEVEL AT 3000' WE STARTED TO ACCUMULATE CLEAR MIXED WITH RIME ICE AT A VERY RAPID RATE. I ASSESSED THE SITUATION AND DETERMINED THAT AT THE RATE WE WERE ACCUMULATING ICE, WE WOULD NOT BE ABLE TO STAY AT 4000' FOR THE NEXT 7 MI. I REQUESTED A LOWER ALT DUE TO THE ICE AND CENTER TOLD ME UNABLE. THE JET HAD NOT PASSED BELOW US. AT THIS PINT I HAD APPLIED FULL PWR TO THE SMA AND RESOLVED TO HOLD MY ALT UNTIL MY AIRSPD DROPPED TO 80 KIAS. THIS I DID AND ALL THE WHILE REQUESTED A LOWER ALT. WHEN MY AIRSPD REACHED 80 KIAS, I AGAIN REQUESTED A LOWER ALT, AND THEY REPLIED THAT DUE TO THE JET, WHICH WAS AT THIS TIME PASSING UNDER, THEY WOULD NOT UNTIL ANOTHER 2 MI. AT THIS POINT I SAID THAT 'LIKE IT OR NOT, I'M COMING DOWN ANYWAY CAUSE I CAN'T HOLD ALT.' HE ASKED IF I WOULD LIKE TO DECLARE AN EMER, BUT I SAID NO. WHEN I WAS DOWN TO 3800', HE VECTORED ME OFF THE APCH AND GAVE ME A DSCNT DOWN TO 2000', SO I DEVIATED MY ALT BY 200' BEFORE HE GAVE ME A LOWER, AND THIS DEVIATION WAS DONE W/O DECLARING AN EMER. I SUPPOSE I COULD HAVE ASKED FOR VECTORS AWAY FROM THE APCH, OR HAVE DECLARED AN EMER BECAUSE I REALLY DIDN'T KNOW HOW MUCH ICE I HAD. AFTER I LANDED, WE STILL HAD 2' ALONG THE LEADING EDGE.

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.

Pilot instructor in small aircraft on training flight encountered icing, but ATC unable lower account traffic. Pilot did not declare emergency, but descended out of assigned altitude.