I am working with a local pilot who has an SR22

I learned today that the auxiliary fuel pump will not supply enough pressure if the engine driven pump fails.

Would any one know why they cannot provide a backup pump to keep things going, or is my understanding wrong.

Seems crazy.

From the SR22 POH (G5, NA) Sec 3, Emergency Procedures



Your understanding is correct, though I don't know why a stronger aux pump was not chosen for the SR.

Here's the POH excerpt from the Emergency Procedures section for the SR22T:


"Engine Driven Fuel Pump Failure: If fuel management is correct,
failure of the engine driven fuel pump or a clogged fuel filter is
probable. An engine driven fuel pump failure is probable when engine
will only operate with fuel pump on HIGH BOOST/PRIME. Reduce
power to 75% or less and land as soon as practical. Do not set the
mixture too rich for descent or landing."


What I understand is that the electric fuel pump in HIGH BOOST / PRIME mode will keep the engine running in the event of a failure of the engine driven fuel pump, although it's possible that may be just for the SR22T.

The boost pump will not provide TOGA performance but should get you around the pattern at 30-40% power. Most turbines won't run in the event of engine driven pump failure Fwiw...