I already posted a lot here about the reliability of the Thielert 125 engines. A new episode in this already long story took place on the 12th of March, when the FAA issued an emergency airworthiness directive requesting: “Before the next flight, install a new high-pressure fuel line and a high-pressure fuel line
bracket”.
This does not concerns directly the high pressure pump, but the fuel line between the high-pressure pump and the common rail. This AD results from reports of in-flight engine shutdowns, as consequences of cracks in high pressure lines resulting from excessive vibrations.
The problem addressed by this AD is certainly serious. As a fan of modern engines, I heard a lot of negative comments on them, and this will certainly create a new wave of criticism.
However I find interesting that this problem is in no way related to software, electronics, FADEC or engine management… but to a fuel line. Even if classical engines don’t have such high-pressure lines, it’s nothing else than a piece of tube. No high-tech or complex thing…
Links:
AOPA information
High-pressure pump – weak point of Thielert engines ?
Side-slips in C172-TDI – High Pressure Pump issue
Vincent Lambercy is a Swiss private pilot now living in Germany. He holds a private pilot certificate with single-engine, multi-engine and instrument ratings and has logged more than 430 hours of flight.
