Kerry Muller:
One thing that I wonder about with Sporty’s backup AI … It is approved to completely take the place of the turn indicator but it seems to me that it operates just like an AI with a turn coordinator stuck on it. So I’m guessing for example, that if you were to slip around a turn with wings relatively level, a turn indicator would show it whereas an AI would not. I think it has something to do with the gyro being canted in a turn indicator.
So with Sporty’s backup AI, do you lose the functionality of the turn indicator?
Editor:
The Sporty’s unit is an Artificial Horizon/Attitude Indicator with an inclinometer mounted on it. It probably does not have the canted gyro; I don’t see how it could, and still show accurate pitch information under all conditions.
The old Turn And Bank instruments also did not have the canted gyro. They were essentially an AH without the pitch information.
The newer Turn Coordinator instruments have the canted gyro so that they can better (marginally better) function as an emergency replacement during an AH failure, by being more sensitive to initial rate of change in roll associated with a change in pitch (did I say that right?!).
With the electric AI, which makes a vastly better alternative to a failed vacuum AI, you get both pitch and roll information. If you are actually slipping or skidding, the superimposed slip-skid ball will still show that.
So my take is that you have gained the additional (vastly better) pitch information, without giving up and roll or slip-skid information.
On top of that, you get a failed-gyro flag, that does not disappear until the rotor is actually up to full speed; you get internal lighting; you get caging capability, in case you are practicing maneuvers that can bang your gyro around; and you get a gyro unit that is most likely better made than the original one in your plane.