Cirrus SR22T: Abnormal Procedures for the Turbocharger

In the event of an unexplained loss of manifold pressure in an SR22T, the engine reverts to operating like a naturally aspirated engine. However, depending on the cause of the anomaly, this could be anything from a benign to a serious event. However, since it is not possible to accurately determine the exact cause, any such event should require an immediate diversion.

  1. Induction leak

This is on the “cold side” of the turbo (i.e with fresh air), and the intake air is leaking out before/after it is pressurized. This is typically not a significant hazard and the only consequence is that the engine reverts to performance of a naturally aspirated engine. Adjust flight profile as necessary and land as soon as possible. However, the next three possibilities on the “hot side” could pose more significant hazards.

  1. Exhaust leak

An exhaust leak prior to the turbocharger could result in an engine fire if the high-velocity and hot exhaust gases interacts with combustible components at any point.

  1. Wastegate failure

Wastegate is held closed by oil pressure. Loss of oil pressure would cause it to open, resulting in a loss of turbo performance. This could be a significant problem as the engine could get starved of oil. Monitor oil pressure.

  1. Turbocharger failure

The turbo is lubricated with oil, and so a failure here could also cause a loss of oil.

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