Narrative:

During cruise flight at FL370 ft the captain; who was the pilot flying; noticed that the left throttle lever was stuck at 94% N1. An attempt was made to apply adequate pressure to loosen the stuck lever but with no luck. The captain then consulted with the company to discuss possible options. After discussing the abnormal situation with me; the first officer; the decision was made to contact flight watch and find out where suitable airports with appropriate weather for our situation [were]. It was determined that the probable cause for the stuck throttle lever was water in the lines that became frozen. As a result we contacted ATC and advised them of our situation and that we would need to descend to a lower altitude and divert. ATC informed us that they would be declaring an emergency on our behalf. During the setup for the divert I ran through various checklist to see if any useful information could be gathered for the situation. The captain also informed our passenger of the situation; and the reason for the divert. On our divert the left throttle became free at an altitude of 13;500 ft with an RAT temperature of +2. At that time the emergency was undeclared and we where given normal routing to the divert airport. We where given vectors for the visual to 26R and told to maintain a speed of 250 KTS. About 3 miles from the final approach fix we where told to maintain 180 KTS or greater until the final approach fix and to contact tower. Due to the distractions of the diversion and the our attempts to begin to configure the aircraft at a short distance to the field and run all appropriate checklist I forget to check in with tower prior to landing. Upon landing I noticed that the tower frequency was still in the scratch pad. I then called tower who gave us instructions to taxi to parking and asked if we saw the green cleared to land to which our response was yes. Obviously in an abnormal situation it is the job of the non flying pilot to provide as much assistance to the flying pilot and the PIC. I simply became too involved with the previous portion of the flight and as a result forgot to switch to the appropriate frequency. In the future it may be advisable to maintain an emergency aircraft status even after the threat has diminished.

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Original NASA ASRS Text

Title: At FL370 BE-400XP throttle froze at 94% because of water in the cable so the flight diverted but during descent at 13;500 FT the throttle released and a normal landing followed.

Narrative: During cruise flight at FL370 FT the Captain; who was the pilot flying; noticed that the left throttle lever was stuck at 94% N1. An attempt was made to apply adequate pressure to loosen the stuck lever but with no luck. The Captain then consulted with the company to discuss possible options. After discussing the abnormal situation with me; the First Officer; the decision was made to contact Flight Watch and find out where suitable airports with appropriate weather for our situation [were]. It was determined that the probable cause for the stuck throttle lever was water in the lines that became frozen. As a result we contacted ATC and advised them of our situation and that we would need to descend to a lower altitude and divert. ATC informed us that they would be declaring an emergency on our behalf. During the setup for the divert I ran through various checklist to see if any useful information could be gathered for the situation. The Captain also informed our passenger of the situation; and the reason for the divert. On our divert the left throttle became free at an altitude of 13;500 FT with an RAT temperature of +2. At that time the emergency was undeclared and we where given normal routing to the divert airport. We where given vectors for the visual to 26R and told to maintain a speed of 250 KTS. About 3 miles from the final approach fix we where told to maintain 180 KTS or greater until the final approach fix and to contact Tower. Due to the distractions of the diversion and the our attempts to begin to configure the aircraft at a short distance to the field and run all appropriate checklist I forget to check in with tower prior to landing. Upon landing I noticed that the Tower frequency was still in the scratch pad. I then called Tower who gave us instructions to taxi to parking and asked if we saw the green cleared to land to which our response was yes. Obviously in an abnormal situation it is the job of the non flying pilot to provide as much assistance to the flying pilot and the PIC. I simply became too involved with the previous portion of the flight and as a result forgot to switch to the appropriate frequency. In the future it may be advisable to maintain an emergency aircraft status even after the threat has diminished.

Data retrieved from NASA's ASRS site as of July 2013 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.