Narrative:

I left on an IFR flight plan. I did my normal/full preflight inspection and completed all checklists. The takeoff and climb were normal. I was at about 8;500 ft just coming up on my cruise altitude of 9;000 ft when I noticed a vibration/shaking that I had never experienced before. As my speed came up at 9;000 ft; the vibration/shaking increased. I looked at engine instruments and all were normal/nominal. I looked at the wings and tail and nothing unusual was apparent. The vibration seemed to be getting worse. I was being handed off by departure but I told the controller I was having an issue with the plane and needed to divert and land immediately. I requested ZZZ; she said - I think - that ZZZ was below minimums and suggested ZZZ1 which was at 700 ft. I took that. I was asked if I was declaring an emergency; I believe I said something like 'not now'; but on the turn back and descent to ZZZ1; the vibration seemed to get worse so I [advised ATC]. I decreased power to approach levels (about 35% power) and descended pretty quickly from 9;000 to 3;000. Once at 3;000 ft and at much lower speeds (about 120 kts) the vibration lessened. I received vectors to the ILS; came out of the clouds at about 800 ft; no issues on the approach or landing. Tower was very helpful; asked details for her report; and contacted a mechanic on field. Once out of the plane; I did a walk around and found the issue: an aerodynamic fiberglass faring at the top of the passenger side landing gear strut had come loose and was dangling about 6 inches below where it should be and would have been disrupting airflow under that wing. After consulting with a cirrus mechanic; I had the faring and wheel pants removed from the landing gear. I did a flight test in the pattern and the plane handled normally. I then flew to where a cirrus mechanic is located for inspection and eventual repairs.

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Original NASA ASRS Text

Title: SR22 pilot experiences an abnormal vibration as he climbs to 9000 feet on an IFR flight plan. When the cause cannot be determined the reporter elects to divert to a suitable airport and lands safely. Post flight reveals that a gear strut fairing at the fuselage is partially detached and the likely cause of the vibration.

Narrative: I left on an IFR flight plan. I did my normal/full preflight inspection and completed all checklists. The Takeoff and climb were normal. I was at about 8;500 ft just coming up on my cruise altitude of 9;000 ft when I noticed a vibration/shaking that I had never experienced before. As my speed came up at 9;000 ft; the vibration/shaking increased. I looked at engine instruments and all were normal/nominal. I looked at the wings and tail and nothing unusual was apparent. The vibration seemed to be getting worse. I was being handed off by Departure but I told the controller I was having an issue with the plane and needed to divert and land immediately. I requested ZZZ; she said - I think - that ZZZ was below minimums and suggested ZZZ1 which was at 700 ft. I took that. I was asked if I was declaring an emergency; I believe I said something like 'not now'; but on the turn back and descent to ZZZ1; the vibration seemed to get worse so I [advised ATC]. I decreased power to approach levels (about 35% power) and descended pretty quickly from 9;000 to 3;000. Once at 3;000 ft and at much lower speeds (about 120 kts) the vibration lessened. I received vectors to the ILS; came out of the clouds at about 800 ft; no issues on the approach or landing. Tower was very helpful; asked details for her report; and contacted a mechanic on field. Once out of the plane; I did a walk around and found the issue: an aerodynamic fiberglass faring at the top of the passenger side landing gear strut had come loose and was dangling about 6 inches below where it should be and would have been disrupting airflow under that wing. After consulting with a Cirrus mechanic; I had the faring and wheel pants removed from the landing gear. I did a flight test in the pattern and the plane handled normally. I then flew to where a Cirrus mechanic is located for inspection and eventual repairs.

Data retrieved from NASA's ASRS site 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.