Narrative:

I was on an IFR training flight with a student. We had filed an IFR flight plan and were proceeding to our first stop. ATC had taken us out over a lake at an altitude of 6;000 ft MSL. We continued on our flight and after a while they directed us to descend to 3;000 ft. I advised 'unable' as it would take us into the clouds. When queried as to why; I advised that we needed to stay in VMC as the aircraft is not certified for IFR flight. This seemed to upset them and they advised to let them know when we could descend. When we arrived over an area that we were able to descend we advised and proceeded down to 3;000 ft. The descent was a little too fast and we wound up going lower than the requested 3;000 MSL down to 2;500 MSL. I immediately requested an altitude lower than 3;000 ft and they gave me 2;700 ft. I went there and proceeded with the approach to sbm. Therefore; I unintentionally had an altitude deviation.I attribute part of the issue to ATC's lack of knowledge of the ability of non-IFR certified aircraft to file IFR and their attitude towards the situation; as well as the request to call them after landing (frankly it was rather upsetting) to be at least partially to blame for the altitude deviation. Of course; the other part of the issue would be a hurried attempt to lose the requested altitude; therefore going to low. To combat this issue in the future I will lose altitude at a more moderate rate; therefore avoiding the issue altogether.

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Original NASA ASRS Text

Title: An R-44 helicopter instructor engaged in pilot training filed an IFR flight plan. During the flight he refused ATC instruction to descend out of VMC into IMC since the aircraft was not certified for IFR flight.

Narrative: I was on an IFR training flight with a student. We had filed an IFR flight plan and were proceeding to our first stop. ATC had taken us out over a lake at an altitude of 6;000 FT MSL. We continued on our flight and after a while they directed us to descend to 3;000 FT. I advised 'unable' as it would take us into the clouds. When queried as to why; I advised that we needed to stay in VMC as the aircraft is not certified for IFR flight. This seemed to upset them and they advised to let them know when we could descend. When we arrived over an area that we were able to descend we advised and proceeded down to 3;000 FT. The descent was a little too fast and we wound up going lower than the requested 3;000 MSL down to 2;500 MSL. I immediately requested an altitude lower than 3;000 FT and they gave me 2;700 FT. I went there and proceeded with the approach to SBM. Therefore; I unintentionally had an altitude deviation.I attribute part of the issue to ATC's lack of knowledge of the ability of non-IFR certified aircraft to file IFR and their attitude towards the situation; as well as the request to call them after landing (frankly it was rather upsetting) to be at least partially to blame for the altitude deviation. Of course; the other part of the issue would be a hurried attempt to lose the requested altitude; therefore going to low. To combat this issue in the future I will lose altitude at a more moderate rate; therefore avoiding the issue altogether.

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.