A first officer and captain report they noticed their engine power levers on their P-180 avanti were...

Attributes
ACN	870926
Time
Date	201001
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	P180 Avanti
Operating Under FAR Part	Part 91
Flight Phase	Descent Cruise
Route In Use	Visual Approach
Flight Plan	IFR
Component
Aircraft Component	Fuselage
Person 1
Function	Pilot Not Flying First Officer
Qualification	Flight Crew Air Transport Pilot (ATP) Flight Crew Flight Instructor Flight Crew Multiengine
Experience	Flight Crew Last 90 Days 150 Flight Crew Total 5500 Flight Crew Type 900
Person 2
Function	Pilot Flying Captain
Qualification	Flight Crew Multiengine Flight Crew Air Transport Pilot (ATP) Flight Crew Instrument
Experience	Flight Crew Last 90 Days 150 Flight Crew Total 6500 Flight Crew Type 1300
Events
Anomaly	Aircraft Equipment Problem Critical Inflight Event / Encounter Loss Of Aircraft Control

Narrative:

Enroute we noticed our power levers were stuck. We then decided to check flight controls and disconnected the autopilot. The rudders were completely frozen and the airplane started a nose dive. It took the both of us plus full trim to bring it back to level flight; 1000 feet below our assigned altitude. When the dive started we immediately informed the controller of the issue. We then reengaged the autopilot and declared an emergency. We decided to divert to ZZZ because of the calm winds; very long runway and warmer temperature for the area. The autopilot was maintaining positive control of the airplane so we did a coupled ILS. A few hundred feet above the ground we disconnected the autopilot and were able to control the pitch with strong pressure. We were able to do a normal landing with no incident. The rudders were still completely frozen. It took both of us heavy pressure to unlock it. We were able to inform the controller of the deviation soon enough to prevent potential problems. As far as the frozen controls; all the necessary steps were taken during the pre-flight; to drain water from the belly of the aircraft.

Original NASA ASRS Text

Title: A First Officer and Captain report they noticed their engine power levers on their P-180 Avanti were sticking after ninety minutes into their flight. Because of heavy rains the night before; they decided to disconnect the autopilot and manually check the flight controls. The P-180 immediately pitched nose down; ice had apparently frozen all six primary flight control cables.

Narrative: Enroute we noticed our power levers were stuck. We then decided to check flight controls and disconnected the autopilot. The rudders were completely frozen and the airplane started a nose dive. It took the both of us plus full trim to bring it back to level flight; 1000 feet below our assigned altitude. When the dive started we immediately informed the Controller of the issue. We then reengaged the autopilot and declared an emergency. We decided to divert to ZZZ because of the calm winds; very long runway and warmer temperature for the area. The autopilot was maintaining positive control of the airplane so we did a coupled ILS. A few hundred feet above the ground we disconnected the autopilot and were able to control the pitch with strong pressure. We were able to do a normal landing with no incident. The rudders were still completely frozen. It took both of us heavy pressure to unlock it. We were able to inform the Controller of the deviation soon enough to prevent potential problems. As far as the frozen controls; all the necessary steps were taken during the pre-flight; to drain water from the belly of the aircraft.

Data retrieved from NASA's ASRS site as of April 2012 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.