Narrative:

It was snowing in cyul when we were scheduled to depart back to ZZZ1; so we informed the deicing company that we would need type 1 & 4 deicing fluid. This was accomplished and we departed. We followed the canadian vnap B procedure; which is basically a climb at a slower than usual speed; with some configuration differences to higher altitudes than we are used to. This was our first time flying in and out of canada as well as our first experience with this type of of departure procedure for noise abatement. My first officer was flying and; as we recall; it was probably around 15;000 feet that he first commented that there was some vibration in the control column. I put my hands on the controls and sensed the same level of vibration; certainly more than normal; almost like getting a hand massage. As we continued our climb he adjusted pitch; power and airspeed to see if the condition would improve or become more aggravated. He felt that the aircraft was under his positive control; responding correctly to his inputs; there was just a strange vibration. We remembered there was a tech note in our SOP that talked about such a vibration; dated back to 1998. Upon level off at 30;000 feet; we reviewed the contents of that tech note to see if there was anything we could do; per emb's recommendations; to figure out what was causing the vibration. We called our flight attendant and asked her if she felt any unusual vibrations in the cabin and reported back that she did not. The tech note talks about vibration stemming from the elevator horn and on page 5 of the tech note there are 2 different ways given to diagnose if this is what you are experiencing. The first was a slight pitch up or down; which is supposed to stop the vibration. In our case; it made the vibration worse. The second was to activate the anti-icing system; which is also supposed to stop the vibration at the horn. This action had no effect; neither aggravating or dissipating the vibration. It seemed to us that the source of the vibration was not in the horn; but we wanted to discuss this with maintenance. We called them up and spoke to them about what we were experiencing; the tech note; and the actions we had taken. They were unfamiliar with the tech note so we gave them a few minutes to locate a copy. No one had knowledge of; or could find this tech note that we have in our SOP. I explained that it could be deice fluid; since that was the only difference between our uneventful flight to cyul; of which I was the pilot flying and had not noticed anything abnormal. They agreed that this could be it; but we could not be certain absent an inspection of the horizontal stabilizer. At this point we could not determine the source of the vibration definitively and neither myself or my first officer felt that we should continue with an undiagnosed flight control abnormality. We noticed that the vibration also worsened as our speed increased; so; to my recollection; we stayed below 260 KIAS. We decided that we needed to put the airplane down soon; as a precaution against the condition worsening. ZZZ1 was still 1 hour away and landing north; so with the concurrence of dispatch; we diverted to ZZZ. We asked dispatch to send us diversion information over ACARS (which was deferred for inaccurate out times; but still sent and received information). We declared an emergency; squawked 7700 and began a cautious approach into ZZZ. We requested for crash fire rescue equipment to be standing by; which they were; conducted a visual approach and taxied to the gate with no further complications. This discrepancy was written up with as much detail as possible to try and aid maintenance in troubleshooting the problem. We also landed somewhere around 200 pounds overweight; but landed under 300 FPM; per the QRH. Elevator flutter possibly caused by contamination of type 4 deicing fluid inside the elevator? This was the first time I have deiced in canada; so I'm not sure if they are aware of the procedure of not spraying ourhorizontal stabilizer from the rear forward? Really all I can do is speculate as to the cause. A flight control abnormality is difficult to describe and even more difficult to diagnose. We both felt that the vibration warranted serious and immediate action to ensure a successful outcome. Emb service newsletter snl 145-49-0007 dated feb 18; 2008; speaks to deice fluid complications in the horizontal stabilizer and recommended inspection cycles to ensure this does not accumulate and dehydrate. If it is determined that there is deice fluid present in the elevator; causing it to be unbalanced and create the control flutter; I would recommend that these scheduled inspections take place to mitigate the risk of a possible re-occurrence in the future. Upon examination by mechanics in ZZZ; they found deice fluid inside the horizontal stabilizer/elevator as well as some bolts that needed to be tightened. I believe the fluid to be a reasonable explanation for unbalancing the elevator; resulting in the flutter and vibration we experienced in the control column.

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Original NASA ASRS Text

Title: EMB145 crew experienced elevator vibration during climbout and cruise after being deiced. Believing that deice fluid may have gotten into the elevator; the crew elected to divert for maintenance inspection.

Narrative: It was snowing in CYUL when we were scheduled to depart back to ZZZ1; so we informed the deicing company that we would need Type 1 & 4 deicing fluid. This was accomplished and we departed. We followed the Canadian VNAP B procedure; which is basically a climb at a slower than usual speed; with some configuration differences to higher altitudes than we are used to. This was our first time flying in and out of Canada as well as our first experience with this type of of departure procedure for noise abatement. My First Officer was flying and; as we recall; it was probably around 15;000 feet that he first commented that there was some vibration in the control column. I put my hands on the controls and sensed the same level of vibration; certainly more than normal; almost like getting a hand massage. As we continued our climb he adjusted pitch; power and airspeed to see if the condition would improve or become more aggravated. He felt that the aircraft was under his positive control; responding correctly to his inputs; there was just a strange vibration. We remembered there was a tech note in our SOP that talked about such a vibration; dated back to 1998. Upon level off at 30;000 feet; we reviewed the contents of that tech note to see if there was anything we could do; per EMB's recommendations; to figure out what was causing the vibration. We called our Flight Attendant and asked her if she felt any unusual vibrations in the cabin and reported back that she did not. The tech note talks about vibration stemming from the elevator horn and on page 5 of the tech note there are 2 different ways given to diagnose if this is what you are experiencing. The first was a slight pitch up or down; which is supposed to stop the vibration. In our case; it made the vibration worse. The second was to activate the anti-icing system; which is also supposed to stop the vibration at the horn. This action had no effect; neither aggravating or dissipating the vibration. It seemed to us that the source of the vibration was not in the horn; but we wanted to discuss this with maintenance. We called them up and spoke to them about what we were experiencing; the tech note; and the actions we had taken. They were unfamiliar with the tech note so we gave them a few minutes to locate a copy. No one had knowledge of; or could find this tech note that we have in our SOP. I explained that it could be deice fluid; since that was the only difference between our uneventful flight to CYUL; of which I was the pilot flying and had not noticed anything abnormal. They agreed that this could be it; but we could not be certain absent an inspection of the horizontal stabilizer. At this point we could not determine the source of the vibration definitively and neither myself or my First Officer felt that we should continue with an undiagnosed flight control abnormality. We noticed that the vibration also worsened as our speed increased; so; to my recollection; we stayed below 260 KIAS. We decided that we needed to put the airplane down soon; as a precaution against the condition worsening. ZZZ1 was still 1 hour away and landing north; so with the concurrence of Dispatch; we diverted to ZZZ. We asked Dispatch to send us diversion information over ACARS (which was deferred for inaccurate out times; but still sent and received information). We declared an emergency; squawked 7700 and began a cautious approach into ZZZ. We requested for CFR to be standing by; which they were; conducted a visual approach and taxied to the gate with no further complications. This discrepancy was written up with as much detail as possible to try and aid Maintenance in troubleshooting the problem. We also landed somewhere around 200 LBS overweight; but landed under 300 FPM; per the QRH. Elevator flutter possibly caused by contamination of type 4 deicing fluid inside the elevator? This was the first time I have deiced in Canada; so I'm not sure if they are aware of the procedure of not spraying ourhorizontal stabilizer from the rear forward? Really all I can do is speculate as to the cause. A flight control abnormality is difficult to describe and even more difficult to diagnose. We both felt that the vibration warranted serious and immediate action to ensure a successful outcome. EMB Service Newsletter SNL 145-49-0007 dated Feb 18; 2008; speaks to deice fluid complications in the horizontal stabilizer and recommended inspection cycles to ensure this does not accumulate and dehydrate. If it is determined that there is deice fluid present in the elevator; causing it to be unbalanced and create the control flutter; I would recommend that these scheduled inspections take place to mitigate the risk of a possible re-occurrence in the future. Upon examination by mechanics in ZZZ; they found deice fluid inside the horizontal stabilizer/elevator as well as some bolts that needed to be tightened. I believe the fluid to be a reasonable explanation for unbalancing the elevator; resulting in the flutter and vibration we experienced in the control column.

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.