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EMB120 aircraft in holding pattern encountered intermittent icing which resulted in an aircraft upset. Aircraft displayed approach to stall characteristics when entering standard rate turn in holding.
| Attributes | |
| ACN | 395823 |
| Time | |
| Date | 199803 |
| Day | Thu |
| Local Time Of Day | 1801 To 2400 |
| Place | |
| Locale Reference | atc facility : sac |
| State Reference | CA |
| Altitude | msl bound lower : 9000 msl bound upper : 10000 |
| Environment | |
| Flight Conditions | Mixed |
| Light | Night |
| Aircraft 1 | |
| Controlling Facilities | tracon : sck |
| Operator | common carrier : air carrier |
| Make Model Name | Brasilia EMB-120 All Series |
| Operating Under FAR Part | Part 121 |
| Navigation In Use | Other |
| Flight Phase | cruise other other other |
| Route In Use | enroute airway : zoa |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Qualification | pilot : instrument pilot : commercial pilot : cfi pilot : atp |
| Experience | flight time last 90 days : 106 flight time total : 4000 flight time type : 921 |
| ASRS Report | 395823 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp |
| Experience | flight time last 90 days : 180 flight time total : 14000 flight time type : 3000 |
| ASRS Report | 395640 |
| Events | |
| Anomaly | altitude deviation : excursion from assigned altitude inflight encounter : weather non adherence : clearance other anomaly |
| Independent Detector | other flight crewa |
| Resolutory Action | flight crew : regained aircraft control flight crew : declared emergency |
| Consequence | Other |
| Supplementary | |
| Primary Problem | Weather |
Narrative:
We departed smf for sfo with a cruising altitude of 9000 ft. During our climb out, we encountered some icing. Once in the hold, we climbed up to 10000 ft to get out of the clouds. At 10000 ft, we were only occasionally in IMC conditions. On our second turn in holding, I felt the aircraft shudder/rumble and scanned the engine instruments, which were normal. Captain added some power. Subsequently, the aircraft shuddered some more and pitched down. The aircraft continued to be unresponsive. I joined captain on the flight controls, trying to counteract the roll. I declared an emergency with stockton approach. Captain increased power to the stops. This still had no effect on the aircraft. Captain then called for flaps 15 degrees. I confirmed this and selected flaps 15 degrees. Shortly thereafter the aircraft started to respond to our inputs. I did notice the airspeed prior to our last outbound turn in holding at something above 160 KTS after our climb to 10000 ft. The slowest I saw the airspeed during this whole event was between 125-130 KTS. After the first scan of the engine instruments I did not note any instruments values. I do not remember looking at the altimeter during this event. Supplemental information from acn 395640: picking up what seemed to be light rime ice. About 1/2 way through the turn, standard rate, left 160 KTS, we both felt a shudder, another, added power. Aircraft rolled strongly to the left, autoplt disconnected, may have had the stick shaker, added power, attempted to level wings and reduce pitch. Aircraft rolled right, still shuddering. Felt we had poor roll and pitch control, firewalled power, saw varying airspds, as low as 120 KTS. Called flaps 15 degrees (they had been up) and had to confirm it. First officer did select them when he was sure I wanted them. Flaps 15 degrees came from a pilot group handout on roll upsets. Feel need to change stall training, especially recovery.
Original NASA ASRS Text
Title: EMB120 ACFT IN HOLDING PATTERN ENCOUNTERED INTERMITTENT ICING WHICH RESULTED IN AN ACFT UPSET. ACFT DISPLAYED APCH TO STALL CHARACTERISTICS WHEN ENTERING STANDARD RATE TURN IN HOLDING.
Narrative: WE DEPARTED SMF FOR SFO WITH A CRUISING ALT OF 9000 FT. DURING OUR CLBOUT, WE ENCOUNTERED SOME ICING. ONCE IN THE HOLD, WE CLBED UP TO 10000 FT TO GET OUT OF THE CLOUDS. AT 10000 FT, WE WERE ONLY OCCASIONALLY IN IMC CONDITIONS. ON OUR SECOND TURN IN HOLDING, I FELT THE ACFT SHUDDER/RUMBLE AND SCANNED THE ENG INSTS, WHICH WERE NORMAL. CAPT ADDED SOME PWR. SUBSEQUENTLY, THE ACFT SHUDDERED SOME MORE AND PITCHED DOWN. THE ACFT CONTINUED TO BE UNRESPONSIVE. I JOINED CAPT ON THE FLT CTLS, TRYING TO COUNTERACT THE ROLL. I DECLARED AN EMER WITH STOCKTON APCH. CAPT INCREASED PWR TO THE STOPS. THIS STILL HAD NO EFFECT ON THE ACFT. CAPT THEN CALLED FOR FLAPS 15 DEGS. I CONFIRMED THIS AND SELECTED FLAPS 15 DEGS. SHORTLY THEREAFTER THE ACFT STARTED TO RESPOND TO OUR INPUTS. I DID NOTICE THE AIRSPD PRIOR TO OUR LAST OUTBOUND TURN IN HOLDING AT SOMETHING ABOVE 160 KTS AFTER OUR CLB TO 10000 FT. THE SLOWEST I SAW THE AIRSPD DURING THIS WHOLE EVENT WAS BTWN 125-130 KTS. AFTER THE FIRST SCAN OF THE ENG INSTS I DID NOT NOTE ANY INSTS VALUES. I DO NOT REMEMBER LOOKING AT THE ALTIMETER DURING THIS EVENT. SUPPLEMENTAL INFO FROM ACN 395640: PICKING UP WHAT SEEMED TO BE LIGHT RIME ICE. ABOUT 1/2 WAY THROUGH THE TURN, STANDARD RATE, L 160 KTS, WE BOTH FELT A SHUDDER, ANOTHER, ADDED PWR. ACFT ROLLED STRONGLY TO THE L, AUTOPLT DISCONNECTED, MAY HAVE HAD THE STICK SHAKER, ADDED PWR, ATTEMPTED TO LEVEL WINGS AND REDUCE PITCH. ACFT ROLLED R, STILL SHUDDERING. FELT WE HAD POOR ROLL AND PITCH CTL, FIREWALLED PWR, SAW VARYING AIRSPDS, AS LOW AS 120 KTS. CALLED FLAPS 15 DEGS (THEY HAD BEEN UP) AND HAD TO CONFIRM IT. FO DID SELECT THEM WHEN HE WAS SURE I WANTED THEM. FLAPS 15 DEGS CAME FROM A PLT GROUP HANDOUT ON ROLL UPSETS. FEEL NEED TO CHANGE STALL TRAINING, ESPECIALLY RECOVERY.
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.