Austro engine reliability and safety

[Boatguy]

Russ, sorry for the delayed response. Here you guys go.

https://www.dropbox.com/scl/fo/vu57l9a0 ... 42swo&dl=0

Thanks.

[ememic99]

I read the documents and I'm interested in opinions. I definitely don't have sufficient knowledge to evaluate the report (the analysis looks very detailed) but I'd like to hear what others think about final conclusion.

[Chris]

I found the report facinating, and it seemed pretty thorough to me. Although I also have very little prior exposure to these types of mechanical failure analyses.

Based on the way the metallurgical changes (and resulting failure) were correlated with the position of the fuel injector, the conclusion seemed plausible to me. An out-of-spec injector, either run past its useful life or perhaps damaged by contaminated fuel, seems like the likely culprit. It's too bad they no longer had the original injectors to confirm the theory.

My question is how long does it take for an injector problem to manifest as a catastriphic failure like this and whether or not there could be some way to test the condition of the injectors (which would presumably require pulling them) to find these problems before that happens.

[michael.g.miller]

In the auto world, yes there is absolutely a way to test these exact injectors. I've been talking with Diamond about if we could do 300 hour tests of injectors instead of a mandatory replacement at 900 hours.

The problem is that in the US, they don't have software / configuration settings for European-style engines. Oh, and of course FAA approval in place of the AD. Unfortunately, no news to report.. but hopefully in the next few years, Diamond/Austro will allow us to use regular injector inspections instead of replacing them wholesale.

[RookieFlyer]

I read the documents and I'm interested in opinions. I definitely don't have sufficient knowledge to evaluate the report (the analysis looks very detailed) but I'd like to hear what others think about final conclusion.

It sounds very similar to NTSB report (Accident No. WPR17LA050) regarding a DA40NG engine failure in Arizona during Dec 2016.

Quote:
"... Multiple similar piston failures have occurred to other engines in the series, seemingly initiated
by either foreign object ingestion and damage or thermal overload due to an out-of-tolerance
fuel injector, or a combination of both.

The manufacturer released a mandatory service bulletin to address the fuel injector defects and
a service letter to address the potential for foreign object ingestion following maintenance
events.

Although not contributing to the accident, during the investigation, a series of cracks were
observed in the cylinder head of both the accident engine and a series of other similar engines.
In one event, a crack led to a loss of coolant after the cooling system became over-pressurized.
In all cases, the cracks had occurred before the engines had reached their service life.

The FAA-certified engine was originally designed and manufactured for automobile use, and
subsequently modified by the manufacturer for aviation use. As such, the engine was not
operating in the manner (continuous high-power operation) for which it was originally
designed. The significance of this finding could not be determined."

[Rich]

Say what you will about the Austro. But the large displacement Continentals are no paragons of reliability. It seems the most common reason for successfully deploying the CAPS has been SR22 engine failures. Causes unknown, of course. Two of these this week. One near Seattle, another in Northern California.

[Soareyes]

Say what you will about the Austro. But the large displacement Continentals are no paragons of reliability. It seems the most common reason for successfully deploying the CAPS has been SR22 engine failures. Causes unknown, of course. Two of these this week. One near Seattle, another in Northern California.

Nor Lycoming, as in the Nashville crash this week. Without CAPS.

[mfdutra]

I believe those two recent CAPS pulls wouldn't be survivable without CAPS. There was nowhere to put those airplanes down safely.

Look at the Nashville outcome. An entire family is dead, including children.

[ememic99]

Look at the Nashville outcome. An entire family is dead, including children.

It’s hard to comment any accident without knowing the facts but this area is full of airports. Comparing to Europe, US are littered with airports which greatly increases safety of flying.

[Soareyes]

Look at the Nashville outcome. An entire family is dead, including children.

It’s hard to comment any accident without knowing the facts but this area is full of airports. Comparing to Europe, US are littered with airports which greatly increases safety of flying.
IMG_2352.jpeg

Apparently even having all those airports around Nashville weren’t enough to save that family.