I went flying today on a MVFR day in Chicagoland and was planning to go through a thin layer and pop up over the clouds for an IFR flight. A bit of background:
The airplane is a C-172 with a standard 6 pack. I did all the preflight and during taxi I made sure the turn coordinator turned in the right directions, which it did. It was a little laggy but it turned the right way, so I figured it was OK and made a mental note to keep my eye on it on climb out. Bases were ~2000 ft AGL, so I had some time in VMC to make sure the turn coordinator was working right, but it never really took much mind share until...
After take off, I went under the hood and entered a climbing left turn just as I got close to the bases. I immediately noticed I was in a much steeper turn than normal (both from still seeing the ground AND the artificial horizon), but the turn coordinator was showing "Standard Rate" in the correct direction.
The turn coordinator did not have the red flag up showing that it wasn't working. Even after pulling the circuit breaker and resetting, the same problem persisted.
Questions:
1) Any ideas on what could have caused this?
2) Had I not noticed the issue on the ground and/or had I not had the VMC buffer to "test" the instrument on climb out, aside from noticing conflicting information with the heading indicator and artificial horizon, how is a pilot meant to know the turn coordinator is malfunctioning without the red flag? Given that the heading indicator and artificial horizon are vac pump driven, my initial inclination would be to trust the turn coordinator if the flag isn't there.
FYI--for those interested, I ended up immediately canceling IFR and proceeding VFR to do practice approaches in VMC.
The airplane is a C-172 with a standard 6 pack. I did all the preflight and during taxi I made sure the turn coordinator turned in the right directions, which it did. It was a little laggy but it turned the right way, so I figured it was OK and made a mental note to keep my eye on it on climb out. Bases were ~2000 ft AGL, so I had some time in VMC to make sure the turn coordinator was working right, but it never really took much mind share until...
After take off, I went under the hood and entered a climbing left turn just as I got close to the bases. I immediately noticed I was in a much steeper turn than normal (both from still seeing the ground AND the artificial horizon), but the turn coordinator was showing "Standard Rate" in the correct direction.
The turn coordinator did not have the red flag up showing that it wasn't working. Even after pulling the circuit breaker and resetting, the same problem persisted.
Questions:
1) Any ideas on what could have caused this?
2) Had I not noticed the issue on the ground and/or had I not had the VMC buffer to "test" the instrument on climb out, aside from noticing conflicting information with the heading indicator and artificial horizon, how is a pilot meant to know the turn coordinator is malfunctioning without the red flag? Given that the heading indicator and artificial horizon are vac pump driven, my initial inclination would be to trust the turn coordinator if the flag isn't there.
FYI--for those interested, I ended up immediately canceling IFR and proceeding VFR to do practice approaches in VMC.